CN112420997B - A method for constructing a metal oxide coating with a controllable thickness in a solution phase - Google Patents

Abstract

The invention discloses a method for constructing a metal oxide coating layer with controllable thickness in a solution phase. The method comprises the following steps: adding a coating substrate material, metal salt and a precipitator into a non-aqueous solvent to obtain a mixed solution; and the precipitates generated by the reaction of the precipitating agent and the metal salt are uniformly deposited on the surface of the coated substrate material to form a coating layer. The coating method provided by the invention is simple and easy to implement, mild in reaction conditions, strong in universality, continuous and complete in obtained coating layer and uniform and controllable in thickness. When the obtained final product material with the core-shell structure is used for a lithium ion battery, the cycle stability and the high-temperature stability of the material can be improved, and the practical value and the application prospect are high.

Description

Translated fromChinese

一种溶液相中构筑厚度可控的金属氧化物包覆层的方法A method for constructing a metal oxide coating with a controllable thickness in a solution phase

技术领域technical field

本发明属于材料领域，具体涉及一种溶液相中构筑厚度可控的金属氧化物包覆层的方法。The invention belongs to the field of materials, and in particular relates to a method for constructing a metal oxide coating layer with a controllable thickness in a solution phase.

背景技术Background technique

锂离子电池相比于传统电池体系，具有能量密度高、工作电压高、无记忆效应、环境友好等优势，在电子产品、电动汽车等领域中得到了广泛应用。为了满足市场日益增长的需求，应开发出具有更高能量密度、功率密度及可靠的安全性能的锂离子电池。正极材料作为锂离子电池的关键组成部分，是决定电池性能好坏的重要因素。因此，发展更高能量密度的锂离子电池，势必对正极材料提出更高的要求。但是，由于正极材料所处的电势较高，且脱锂态正极材料具有较强的氧化性，易与电解液发生副反应，导致材料结构劣化，造成电化学性能恶化。对正极材料表面进行包覆改性是改善正极材料电化学性能的重要手段之一。Compared with traditional battery systems, lithium-ion batteries have the advantages of high energy density, high operating voltage, no memory effect, and environmental friendliness, and have been widely used in electronic products, electric vehicles and other fields. In order to meet the growing demands of the market, lithium-ion batteries with higher energy density, power density and reliable safety performance should be developed. As a key component of lithium-ion batteries, the cathode material is an important factor determining the performance of the battery. Therefore, the development of lithium-ion batteries with higher energy density is bound to put forward higher requirements for cathode materials. However, due to the high potential of the positive electrode material and the strong oxidizing property of the delithiated positive electrode material, it is prone to side reactions with the electrolyte, resulting in the deterioration of the material structure and the deterioration of the electrochemical performance. Coating and modifying the surface of the cathode material is one of the important means to improve the electrochemical performance of the cathode material.

金属氧化物由于具有稳定的化学性质，常被用作正极材料表面包覆改性的物质。大量研究工作表明，在正极材料表面引入金属氧化物包覆层，可以避免正极材料与电解液直接接触，降低副反应发生的几率，有效提升材料结构稳定性，从而使材料电化学性能得到显著提升。构筑金属氧化物包覆层最常用的方法为液相沉积法，通过在水溶液中利用碱性沉淀剂沉淀金属盐，使产物沉积在材料表面从而获得包覆物质。但是此方法存在很多问题，例如由于金属盐在水溶液中易快速水解，沉淀过程难以控制，因而得到的包覆层效果差，均匀性、连续性及厚度均无法得到有效调节，不能最大限度地优化电极材料性能。原子层沉积法是获得良好包覆效果的主要手段，但是此法所涉及的设备价格昂贵、成本高、对样品处理能力有限，不适用于大规模生产应用。因此，基于实际应用对合成方案提出的要求，结合液相过程适用范围广、工艺简单、成本低的特点，开发可行的液相体系以实现包覆层的精准构筑具有重要的研究意义。发明专利CN201310545860.9报道了一种可控构筑均匀三氧化二铝包覆层的方法。通过在水溶液中添加酸性缓冲溶液调节反应体系的pH值，能够对金属离子沉淀过程进行动力学控制，从而实现金属氧化物包覆层的精准构筑，包覆层均匀连续，且厚度精确可调。但是，此法所涉及的水溶液反应体系会不适用于吸湿性强的电极材料特别是目前备受关注的高镍三元正极材料，由于对水分尤其敏感，不能在水溶液中进行处理。此外，此法需要使用酸性缓冲溶液来抑制金属离子的快速沉淀，会对材料结构造成腐蚀。因此，开发基于非水反应体系的构筑方案，以实现材料表面的无损处理具有重要的研究价值。此外，还需要在非水体系中获得包覆层的精准构筑，以最大限度优化材料的性能。因此，如何通过合理设计合成方案，在确保核材料无损处理的前提下，实现物质沉淀过程的有效控制，从而获得包覆层的精准构筑，是目前面临的一大挑战。Due to their stable chemical properties, metal oxides are often used as surface coating modification substances for cathode materials. A large number of research works have shown that the introduction of a metal oxide coating layer on the surface of the positive electrode material can avoid the direct contact between the positive electrode material and the electrolyte, reduce the probability of side reactions, and effectively improve the structural stability of the material, thereby significantly improving the electrochemical performance of the material. . The most common method for constructing the metal oxide coating layer is the liquid phase deposition method. The coating substance is obtained by precipitating the metal salt with an alkaline precipitant in an aqueous solution, and depositing the product on the surface of the material. However, there are many problems in this method. For example, due to the rapid hydrolysis of metal salts in the aqueous solution, the precipitation process is difficult to control, so the obtained coating layer has poor effect, and the uniformity, continuity and thickness cannot be effectively adjusted, and cannot be optimized to the maximum extent. Electrode material properties. Atomic layer deposition is the main method to obtain good coating effect, but the equipment involved in this method is expensive, high in cost, and limited in sample handling capacity, so it is not suitable for large-scale production applications. Therefore, it is of great significance to develop a feasible liquid-phase system to realize the precise construction of the coating layer based on the requirements of the practical application for the synthesis scheme, combined with the characteristics of the liquid-phase process with wide application range, simple process and low cost. Invention patent CN201310545860.9 reports a method for controllably constructing a uniform Al2O3 coating layer. By adding an acidic buffer solution to the aqueous solution to adjust the pH value of the reaction system, the kinetic control of the metal ion precipitation process can be performed, thereby realizing the precise construction of the metal oxide coating layer, the coating layer is uniform and continuous, and the thickness is precisely adjustable. However, the aqueous reaction system involved in this method is not suitable for electrode materials with strong hygroscopicity, especially the high-nickel ternary cathode materials that have attracted much attention at present. Since they are particularly sensitive to moisture, they cannot be processed in aqueous solutions. In addition, this method requires the use of an acidic buffer solution to inhibit the rapid precipitation of metal ions, which can cause corrosion to the material structure. Therefore, it is of great research value to develop a construction scheme based on non-aqueous reaction systems to achieve non-destructive treatment of material surfaces. In addition, precise construction of the cladding layer in non-aqueous systems is required to maximize the performance of the material. Therefore, how to effectively control the material precipitation process and obtain the precise construction of the cladding layer on the premise of ensuring the non-destructive treatment of nuclear materials by rationally designing the synthesis scheme is a major challenge currently facing.

发明内容SUMMARY OF THE INVENTION

本发明的第一个目的是提供一种基于非水溶剂中在材料表面实现精准、无损构筑金属氧化物包覆层的方法。The first object of the present invention is to provide a method for realizing precise and non-destructive construction of a metal oxide coating layer on the surface of a material based on a non-aqueous solvent.

本发明提供一种金属氧化物的包覆方法，该方法包括如下步骤：在非水溶剂中加入包覆底物材料、金属盐和沉淀剂，得到混合液；所述沉淀剂与金属盐反应生成的沉淀均匀沉积在所述包覆底物材料的表面，形成金属氧化物包覆层。The present invention provides a method for coating metal oxides. The method comprises the following steps: adding a coating substrate material, a metal salt and a precipitating agent to a non-aqueous solvent to obtain a mixed solution; the precipitating agent reacts with the metal salt to generate The precipitates are uniformly deposited on the surface of the coating substrate material to form a metal oxide coating layer.

根据本发明的技术方案，所述非水溶剂选自无水有机溶剂，例如选自无水醇溶剂和/或无水酮溶剂；优选地，所述非水溶剂选自无水的甲醇、乙醇、丙醇、丁醇、乙二醇、丙二醇、正丙醇、异丙醇、正丁醇和丙酮中的至少一种；更优选为无水乙醇。进一步地，所述非水溶剂的纯度为色谱纯级别，其含水量≤0.1wt％。According to the technical solution of the present invention, the non-aqueous solvent is selected from anhydrous organic solvents, for example, selected from anhydrous alcohol solvent and/or anhydrous ketone solvent; preferably, the non-aqueous solvent is selected from anhydrous methanol, ethanol , at least one of propanol, butanol, ethylene glycol, propylene glycol, n-propanol, isopropanol, n-butanol and acetone; more preferably absolute ethanol. Further, the purity of the non-aqueous solvent is chromatographic grade, and its water content is less than or equal to 0.1 wt%.

根据本发明的技术方案，所述包覆底物材料选自金属、氧化物、碳化物、硫化物、磷化物、氮化物、锂盐、磷酸盐、非金属和有机物颗粒中的至少一种；According to the technical solution of the present invention, the coating substrate material is selected from at least one of metal, oxide, carbide, sulfide, phosphide, nitride, lithium salt, phosphate, non-metal and organic particles;

其中，所述金属选自以下金属及其形成的合金中的至少一种：金、银、钯、铂、钌、铑、锡、锗和锑；Wherein, the metal is selected from at least one of the following metals and alloys thereof: gold, silver, palladium, platinum, ruthenium, rhodium, tin, germanium and antimony;

其中，所述氧化物选自二氧化硅、二氧化锡、三氧化二铝、氧化钼、五氧化二钒、二氧化钛、四氧化三锰、四氧化三钴、二氧化锆、氧化锌、二氧化铈、氧化镁、氧化钙、氧化铟、氧化镓、氧化锂、四氧化三铁和锂镧锆氧中的至少一种；优选为二氧化硅和/或二氧化锡；Wherein, the oxide is selected from silicon dioxide, tin dioxide, aluminum oxide, molybdenum oxide, vanadium pentoxide, titanium dioxide, manganese tetroxide, cobalt tetroxide, zirconium dioxide, zinc oxide, ceria, oxide At least one of magnesium, calcium oxide, indium oxide, gallium oxide, lithium oxide, triiron tetroxide and lithium lanthanum zirconium oxide; preferably silicon dioxide and/or tin dioxide;

其中，所述碳化物选自碳化钙、碳化钛、碳化铬、碳化钒、碳化钨、碳化硅、碳化硼和碳化钽中的至少一种；Wherein, the carbide is selected from at least one of calcium carbide, titanium carbide, chromium carbide, vanadium carbide, tungsten carbide, silicon carbide, boron carbide and tantalum carbide;

其中，所述硫化物选自硫化钼、硫化锌、硫化镍、硫化钴、硫化铋、硫化锡、硫化钨、硫化锑和二硫化钛中的至少一种；Wherein, the sulfide is selected from at least one of molybdenum sulfide, zinc sulfide, nickel sulfide, cobalt sulfide, bismuth sulfide, tin sulfide, tungsten sulfide, antimony sulfide and titanium disulfide;

其中，所述磷化物选自磷化钴、磷化钼、磷化钛、磷化镍、磷化铁和磷化锡中的至少一种；Wherein, the phosphide is selected from at least one of cobalt phosphide, molybdenum phosphide, titanium phosphide, nickel phosphide, iron phosphide and tin phosphide;

其中，所述氮化物选自氮化镓、氮化硼、氮化硅、氮化磷、氮化钨、氮化钒、氮化钛、氮化铌和氮化锂中的至少一种；Wherein, the nitride is selected from at least one of gallium nitride, boron nitride, silicon nitride, phosphorus nitride, tungsten nitride, vanadium nitride, titanium nitride, niobium nitride and lithium nitride;

其中，所述锂盐选自锰酸锂、钴酸锂、镍酸锂、镍锰酸锂、镍锰钴酸锂、镍钴铝酸锂、镍钴酸锂、富锂镍钴锰酸锂和钛酸锂中的至少一种；优选为镍锰酸锂、镍锰钴酸锂、镍钴铝酸锂和钛酸锂中的至少一种；Wherein, the lithium salt is selected from lithium manganate, lithium cobaltate, lithium nickelate, lithium nickel manganate, lithium nickel manganese cobaltate, lithium nickel cobalt aluminate, lithium nickel cobalt oxide, lithium rich nickel cobalt manganate and At least one of lithium titanate; preferably at least one of lithium nickel manganese oxide, lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminate and lithium titanate;

其中，所述磷酸盐选自磷酸铁、磷酸钛、磷酸钛锂、磷酸钛铝锂、磷酸铁锂、磷酸钴锂、磷酸锰锂、磷酸锰钴锂、磷酸铁锰锂、磷酸钒锂和磷酸钒钠中的至少一种；Wherein, the phosphate is selected from iron phosphate, titanium phosphate, lithium titanium phosphate, lithium aluminum titanium phosphate, lithium iron phosphate, lithium cobalt phosphate, lithium manganese phosphate, lithium manganese cobalt phosphate, lithium iron manganese phosphate, lithium vanadium phosphate and phosphoric acid At least one of sodium vanadium;

其中，所述非金属选自碳、碳纳米管、石墨烯、氧化石墨烯、富勒烯、硅、磷、硫、硒、碲和硼中的至少一种；Wherein, the non-metal is selected from at least one of carbon, carbon nanotubes, graphene, graphene oxide, fullerenes, silicon, phosphorus, sulfur, selenium, tellurium and boron;

其中，所述有机物颗粒选自酚醛树脂、脲醛树脂、三聚氰胺树脂、聚苯乙烯、聚乙烯吡咯烷酮、聚多巴胺、葡萄糖、壳聚糖和果糖中的至少一种。Wherein, the organic particles are selected from at least one of phenolic resin, urea-formaldehyde resin, melamine resin, polystyrene, polyvinylpyrrolidone, polydopamine, glucose, chitosan and fructose.

根据本发明的技术方案，所述金属盐选自所述金属对应的氯化盐、硫酸盐、硝酸盐、醋酸盐、乙酰丙酮盐、乳酸盐和醇盐中的至少一种；例如选自硝酸盐；示例性地，选自硝酸铁或其水合物，硝酸锆或其水合物。According to the technical solution of the present invention, the metal salt is selected from at least one of chloride salts, sulfates, nitrates, acetates, acetylacetonates, lactates and alkoxides corresponding to the metals; From nitrate; exemplarily, selected from ferric nitrate or its hydrate, zirconium nitrate or its hydrate.

根据本发明的技术方案，所述沉淀剂选自尿素、甲酰胺、乙酰胺、丙酰胺、三乙醇胺、六次甲基四胺、氨水、甲酸铵、乙酸铵、丙酸铵、碳酸氢铵、碳酸铵、磷酸铵、磷酸氢二铵、磷酸二氢铵、氢氧化锂、氢氧化钠和氢氧化钾中的至少一种；例如选自六次甲基四胺或氢氧化锂。According to the technical scheme of the present invention, the precipitating agent is selected from urea, formamide, acetamide, propionamide, triethanolamine, hexamethylenetetramine, ammonia water, ammonium formate, ammonium acetate, ammonium propionate, ammonium bicarbonate, At least one of ammonium carbonate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, lithium hydroxide, sodium hydroxide and potassium hydroxide; for example, selected from hexamethylenetetramine or lithium hydroxide.

根据本发明的技术方案，所述混合液中，包覆底物材料的浓度为0.01～100g/L；例如浓度为0.5～50g/L、1～10g/L；示例性地，浓度为1.67g/L、3.33g/L、6.67g/L。According to the technical solution of the present invention, in the mixed solution, the concentration of the coating substrate material is 0.01-100 g/L; for example, the concentration is 0.5-50 g/L, 1-10 g/L; exemplarily, the concentration is 1.67 g /L, 3.33g/L, 6.67g/L.

根据本发明的技术方案，所述包覆底物材料的平均粒径为10nm～20μm；例如20nm～10μm、50nm～5μm、100nm～1μm；示例性地，平均粒径为200nm或600nm。According to the technical solution of the present invention, the average particle size of the coating substrate material is 10 nm-20 μm; for example, 20 nm-10 μm, 50 nm-5 μm, 100 nm-1 μm; exemplarily, the average particle size is 200 nm or 600 nm.

根据本发明的技术方案，所述混合液中，金属盐的浓度为1×10^-4～0.1mol/L；例如浓度为1×10^-3～0.05mol/L、5×10^-3～0.01mol/L；示例性地，浓度为8.2×10^-3mol/L、2×10^-4mol/L。According to the technical solution of the present invention, in the mixed solution, the concentration of the metal salt is 1×10^-4 to 0.1mol/L; for example, the concentration is 1×10^-3 to 0.05mol/L, 5×10^-3 to 0.01 mol/L; exemplarily, the concentrations are 8.2×10⁻³ mol/L, 2×10⁻⁴ mol/L.

根据本发明的技术方案，所述混合液中，沉淀剂的浓度为1×10^-3～1mol/L；例如，浓度为5×10^-3～0.5mol/L、1×10^-2～0.1mol/L；示例性地，浓度为0.024mol/L、0.004mol/L。According to the technical solution of the present invention, in the mixed solution, the concentration of the precipitant is 1×10^-3 to 1mol/L; for example, the concentration is 5×10^-3 to 0.5mol/L, 1×10^-2 to 0.1 mol/L; exemplarily, the concentrations are 0.024 mol/L, 0.004 mol/L.

根据本发明的技术方案，所述反应的温度为10～100℃，例如为50-90℃，示例性地，温度为80℃。According to the technical solution of the present invention, the temperature of the reaction is 10-100°C, for example, 50-90°C, and exemplarily, the temperature is 80°C.

根据本发明的技术方案，所述反应的时间为0.5h～10h，例如为2-8h，示例性地，时间为4h。According to the technical solution of the present invention, the reaction time is 0.5h-10h, for example, 2-8h, and exemplarily, the time is 4h.

根据本发明的技术方案，所述方法还包括对含有金属包覆层的金属氧化物进行煅烧处理，得到以金属氧化物为壳层的核-壳结构包覆型颗粒。According to the technical solution of the present invention, the method further includes calcining the metal oxide containing the metal coating layer to obtain core-shell structure coated particles with the metal oxide as the shell layer.

其中，所述煅烧的气氛为空气、氧气、氮气、氩气、氢气/氩气混合气中的至少一种；优选为空气或氧气。Wherein, the calcining atmosphere is at least one of air, oxygen, nitrogen, argon, and hydrogen/argon gas mixture; preferably air or oxygen.

其中，所述煅烧的温度为400～1000℃，例如温度为500～800℃，示例性地，温度为500℃、700℃。Wherein, the temperature of the calcination is 400-1000°C, for example, the temperature is 500-800°C, exemplarily, the temperature is 500°C and 700°C.

其中，所述煅烧的时间为0.5～10h，例如时间为1-5h，示例性地，时间为2h、4h。Wherein, the calcination time is 0.5-10 h, for example, the time is 1-5 h, exemplarily, the time is 2 h, 4 h.

根据本发明的实施方案，所述方法包括如下步骤：According to an embodiment of the present invention, the method comprises the steps of:

(1)在非水溶剂中加入包覆底物材料、金属硝酸盐和沉淀剂，得到混合液；所述沉淀剂与金属盐反应生成的沉淀均匀沉积在所述包覆底物材料的表面，形成包覆层；(1) adding a coating substrate material, a metal nitrate and a precipitant in a non-aqueous solvent to obtain a mixed solution; the precipitation generated by the reaction of the precipitating agent and the metal salt is uniformly deposited on the surface of the coating substrate material, forming a coating;

所述包覆底物材料选自氧化物或锂盐；The coating substrate material is selected from oxides or lithium salts;

(2)对步骤(1)得到的含有金属包覆层的金属氧化物进行煅烧，得到以金属氧化物为壳层的核-壳结构包覆型颗粒。(2) calcining the metal oxide containing the metal coating layer obtained in step (1) to obtain core-shell structure coated particles with the metal oxide as the shell layer.

进一步地，本发明第二个目的提供由上述方法制备得到的以金属氧化物为壳层的核-壳结构包覆型颗粒。其中，所述壳层均匀、连续、完整地包覆在所述包覆底物材料上，且包覆底物材料表面无损。优选地，所述金属氧化物可以为三氧化二铁、二氧化锆。进一步地，所述壳层的厚度为1-200nm，例如3-100nm、5-50nm，示例性地，厚度为3nm、5nm、9nm、10nm、25nm、28nm、32nm、45nm。其中，所述核为所述包覆底物材料。Further, the second object of the present invention is to provide core-shell structure coated particles with metal oxides as shell layers prepared by the above method. Wherein, the shell layer is uniformly, continuously and completely coated on the coated substrate material, and the surface of the coated substrate material is not damaged. Preferably, the metal oxide can be ferric oxide and zirconium dioxide. Further, the thickness of the shell layer is 1-200 nm, such as 3-100 nm, 5-50 nm, exemplarily, the thickness is 3 nm, 5 nm, 9 nm, 10 nm, 25 nm, 28 nm, 32 nm, 45 nm. Wherein, the core is the coating substrate material.

根据本发明的实施方案，所述核-壳结构包覆型颗粒可以为三氧化二铁包覆的二氧化硅、三氧化二铁包覆的二氧化锡、三氧化二铁包覆的镍钴锰酸锂、三氧化二铁包覆的镍钴铝酸锂、三氧化二铁包覆的钛酸锂、三氧化二铁包覆的镍锰酸锂、二氧化锆包覆的二氧化硅、二氧化锆包覆的镍锰酸锂。According to an embodiment of the present invention, the core-shell structure-coated particles may be ferric oxide-coated silica, ferric oxide-coated tin dioxide, and ferric oxide-coated nickel-cobalt particles Lithium manganate, ferric oxide-coated nickel-cobalt aluminate, ferric oxide-coated lithium titanate, ferric oxide-coated lithium nickel manganate, zirconium dioxide-coated silica, Zirconium dioxide coated lithium nickel manganate.

本发明方法中，在所利用的非水溶剂中，反应物离子活度减弱，金属盐水解得到有效抑制，沉淀剂能够缓慢与金属盐发生反应，逐渐生成沉淀，并均匀、连续地沉积在包覆底物材料的表面，从而获得完整、厚度可控的包覆层。经过煅烧处理，得到以金属氧化物为壳的核-壳结构包覆型颗粒。In the method of the present invention, in the used non-aqueous solvent, the ionic activity of the reactant is weakened, the hydrolysis of the metal salt is effectively suppressed, and the precipitant can slowly react with the metal salt to gradually form a precipitate, which is uniformly and continuously deposited on the package. The surface of the substrate material is coated to obtain a complete coating with controllable thickness. After calcination treatment, core-shell structure coated particles with metal oxides as shells are obtained.

进一步地，本发明第三个目的提供所述方法得到的具有核-壳结构的包覆型颗粒在锂电池中的应用，优选作为锂电池的正极材料。Further, the third object of the present invention is to provide the application of the coated particles with a core-shell structure obtained by the method in a lithium battery, preferably as a positive electrode material for a lithium battery.

进一步地，本发明还提供一种含有所述核-壳结构包覆型颗粒的锂离子正极材料。Further, the present invention also provides a lithium ion positive electrode material containing the core-shell structure coated particles.

根据本发明的实施方案，当所述核-壳结构包覆型颗粒的核选自所述锂盐时，所述锂离子正极材料即为所述核-壳结构包覆型颗粒。According to an embodiment of the present invention, when the core of the core-shell structure coated particle is selected from the lithium salt, the lithium ion positive electrode material is the core-shell structure coated particle.

根据本发明的实施方案，当所述核-壳结构包覆型颗粒的核选自非所述锂盐时，所述锂离子正极材料可由所述核-壳结构包覆型颗粒锂化处理得到。进一步地，所述的锂化包括如下步骤：所述核-壳结构包覆型颗粒与氢氧化锂或碳酸锂混合烧结。其中，所述核-壳结构包覆型颗粒与氢氧化锂或碳酸锂的摩尔比为1:(1-1.1)，例如1:(1-1.08)、1:(1.02-1.06)。所述烧结在含氧气氛下进行，例如空气或氧气气氛下。所述烧结的温度为400-1000℃，例如500-900℃、600-800℃。所述烧结的时间为1-10h，例如2-8h、4-6h。所述烧结可以为一步烧结，或两次以上的多步烧结，每步烧结温度和时间可以相同或不同。According to an embodiment of the present invention, when the core of the core-shell structure-coated particle is selected from a non-lithium salt, the lithium ion positive electrode material can be obtained by lithiation of the core-shell structure-coated particle . Further, the lithiation includes the following steps: the core-shell structure coated particles are mixed and sintered with lithium hydroxide or lithium carbonate. Wherein, the molar ratio of the core-shell structure-coated particles to lithium hydroxide or lithium carbonate is 1:(1-1.1), for example, 1:(1-1.08), 1:(1.02-1.06). The sintering is carried out in an oxygen-containing atmosphere, such as air or oxygen. The sintering temperature is 400-1000°C, such as 500-900°C, 600-800°C. The sintering time is 1-10h, such as 2-8h, 4-6h. The sintering can be one-step sintering, or two or more multi-step sintering, and the sintering temperature and time of each step can be the same or different.

进一步地，本发明还提供一种含有所述核-壳结构包覆型颗粒或含有所述锂离子正极材料的锂离子电池。Further, the present invention also provides a lithium ion battery containing the core-shell structure coated particles or containing the lithium ion positive electrode material.

由本发明的具有核-壳结构的金属氧化物包覆型颗粒对锂离子电池或锂电池的正极材料进行原位厚度可控的包覆后得到的金属氧化物包覆型正极材料，能够作为高能量型储能器件的锂离子电池或锂电池的正极材料。The metal oxide-coated positive electrode material obtained by the in-situ thickness-controllable coating of the positive electrode material of a lithium ion battery or a lithium battery by the metal oxide-coated particles having a core-shell structure of the present invention can be used as a high Lithium-ion battery or positive electrode material of lithium battery for energy storage device.

本发明的有益效果：Beneficial effects of the present invention:

本发明提供了一种能够在非水环境中实现金属氧化物包覆层精准构筑的方法，工艺简单、反应条件温和，对核材料表面能够实现无损处理，适用范围广。该方法基于非水溶剂提供的反应环境，能够减弱反应物的离子活度，抑制金属离子的水解，有效控制金属盐的沉淀过程，实现沉淀物析出方式的调节，从而获得材料表面均匀连续的包覆层，且厚度可在纳米精度范围内调控。通过进一步的煅烧处理即可得到所述的金属氧化物包覆的核-壳结构颗粒。以此方法得到的金属氧化物包覆锂离子电池正极材料的核-壳结构颗粒，能够表现出优异的电化学性能。The invention provides a method for realizing precise construction of a metal oxide coating layer in a non-aqueous environment, with simple process, mild reaction conditions, non-destructive treatment of the surface of the nuclear material, and wide application range. The method is based on the reaction environment provided by the non-aqueous solvent, which can weaken the ionic activity of the reactants, inhibit the hydrolysis of metal ions, effectively control the precipitation process of metal salts, and realize the adjustment of the precipitation method, so as to obtain uniform and continuous encapsulation on the surface of the material. coating, and the thickness can be adjusted in the nanometer precision range. The metal oxide-coated core-shell structure particles can be obtained by further calcination treatment. The core-shell structure particles of the metal oxide-coated cathode material of lithium ion batteries obtained in this way can exhibit excellent electrochemical performance.

本发明提供的金属氧化物包覆型颗粒，可以在不同包覆底物的表面上得到均匀、连续、完整且厚度可控的金属氧化物包覆层，且确保材料表面获得无损处理。本发明利用非水溶剂提供的反应环境，减弱反应物的离子活度，抑制金属盐的水解，使金属盐的沉淀过程变得可控，从而获得对沉淀析出方式的调控，成功实现均匀、连续、完整、厚度可控包覆层的制备。本发明提供的包覆方法工艺简单、普适性强、能够实现材料表面无损处理，获得的包覆层均匀、连续、完整、厚度可实现纳米精度内精确调节，在高能量型储能器件即锂离子电池或锂电池领域有着很高的实用性和应用前景。The metal oxide-coated particles provided by the present invention can obtain a uniform, continuous, complete and controllable thickness of the metal oxide coating layer on the surfaces of different coating substrates, and ensure that the surface of the material can be non-destructively treated. The invention utilizes the reaction environment provided by the non-aqueous solvent, weakens the ionic activity of the reactants, inhibits the hydrolysis of the metal salt, and makes the precipitation process of the metal salt controllable, so as to obtain the regulation of the precipitation and precipitation mode, and successfully realize uniform and continuous , Preparation of complete, thickness-controllable coating. The coating method provided by the invention has simple process, strong universality, and can realize non-destructive treatment of material surface. The obtained coating layer is uniform, continuous and complete, and the thickness can be precisely adjusted within nanometer precision. The field of lithium ion batteries or lithium batteries has high practicability and application prospects.

附图说明Description of drawings

图1为实施例1的三氧化二铁包覆二氧化硅颗粒的透射电子显微镜照片。FIG. 1 is a transmission electron microscope photograph of the ferric oxide-coated silica particles of Example 1. FIG.

图2为实施例2的三氧化二铁包覆二氧化锡颗粒的透射电子显微镜照片。FIG. 2 is a transmission electron microscope photograph of the ferric oxide-coated tin dioxide particles of Example 2. FIG.

图3为实施例3的三氧化二铁包覆镍钴锰酸锂颗粒的透射电子显微镜照片。3 is a transmission electron microscope photograph of the ferric oxide-coated nickel cobalt lithium manganate particles of Example 3. FIG.

图4为实施例4的三氧化二铁包覆镍钴铝酸锂颗粒的透射电子显微镜照片。FIG. 4 is a transmission electron microscope photograph of the ferric oxide-coated nickel-cobalt aluminate particles of Example 4. FIG.

图5为实施例5的三氧化二铁包覆钛酸锂颗粒的透射电子显微镜照片。FIG. 5 is a transmission electron microscope photograph of the Fe2O3-coated lithium titanate particles of Example 5. FIG.

图6为实施例6的二氧化锆包覆二氧化硅颗粒的透射电子显微镜照片。6 is a transmission electron microscope photograph of the zirconia-coated silica particles of Example 6. FIG.

图7为实施例7的二氧化锆包覆镍锰酸锂颗粒的透射电子显微镜照片。FIG. 7 is a transmission electron microscope photograph of the zirconium dioxide-coated lithium nickel manganate particles of Example 7. FIG.

图8为实施例8的三氧化二铁包覆镍锰酸锂颗粒的透射电子显微镜照片。FIG. 8 is a transmission electron microscope photograph of the Fe2O3-coated lithium nickel manganate particles of Example 8. FIG.

图9为实施例8的三氧化二铁包覆镍锰酸锂颗粒在0.1C下的循环性能。FIG. 9 shows the cycle performance of the Fe2O3-coated lithium nickel manganate particles of Example 8 at 0.1C.

图10为对比例1的以去离子水为溶剂下三氧化二铁包覆二氧化硅颗粒的透射电子显微镜照片。FIG. 10 is a transmission electron microscope photograph of Fe2O3-coated silica particles using deionized water as a solvent of Comparative Example 1. FIG.

图11为对比例2的以去离子水为溶剂下二氧化锆包覆二氧化硅颗粒的透射电子显微镜照片。11 is a transmission electron microscope photograph of zirconium dioxide-coated silica particles of Comparative Example 2 using deionized water as a solvent.

具体实施方式Detailed ways

下文将结合具体实施例对本发明的技术方案做更进一步的详细说明。应当理解，下列实施例仅为示例性地说明和解释本发明，而不应被解释为对本发明保护范围的限制。凡基于本发明上述内容所实现的技术均涵盖在本发明旨在保护的范围内。The technical solutions of the present invention will be described in further detail below with reference to specific embodiments. It should be understood that the following examples are only for illustrating and explaining the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the intended protection scope of the present invention.

除非另有说明，以下实施例中使用的原料和试剂均为市售商品，或者可以通过已知方法制备。Unless otherwise stated, the starting materials and reagents used in the following examples are commercially available or can be prepared by known methods.

以下实施例中所用到的无水乙醇为色谱纯级别，其含水量≤0.1wt％。The absolute ethanol used in the following examples is of chromatographically pure grade, and its water content is less than or equal to 0.1 wt%.

实施例1Example 1

制备三氧化二铁包覆的二氧化硅颗粒Preparation of Fe2O3-Coated Silica Particles

(1)将二氧化硅颗粒0.05g(平均粒径为600nm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的二氧化硅颗粒，再在500℃空气气氛下煅烧2h，得到三氧化二铁包覆的二氧化硅颗粒。(1) Mix 0.05 g of silica particles (average particle size of 600 nm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent absolute ethanol, and reflux at 80°C with stirring The reaction was carried out for 4 hours, centrifuged, washed and dried to obtain iron-coated silica particles, and then calcined in an air atmosphere at 500° C. for 2 hours to obtain ferric oxide-coated silica particles.

(2)该三氧化二铁包覆的二氧化硅颗粒为核-壳结构，其电镜照片如图1所示。构成核的材料为粒径为600nm的二氧化硅，构成壳的材料为三氧化二铁，厚度为32nm；且三氧化二铁连续、均匀、完整地包覆在二氧化硅的表面，且二氧化硅表面为无损包覆。(2) The ferric oxide-coated silica particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 1 . The material constituting the core is silica with a particle size of 600 nm, and the material constituting the shell is ferric oxide with a thickness of 32 nm; and the ferric oxide is continuously, uniformly and completely coated on the surface of the silica, and the two The silicon oxide surface is a non-destructive coating.

实施例2Example 2

制备三氧化二铁包覆的二氧化锡颗粒Preparation of ferric oxide-coated tin dioxide particles

(1)将二氧化锡颗粒0.05g(粒径为20～100nm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的二氧化锡颗粒，再在500℃空气气氛下煅烧2h，得到三氧化二铁包覆的二氧化锡颗粒。(1) Mix 0.05 g of tin dioxide particles (with a particle size of 20 to 100 nm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent anhydrous ethanol, and stir at 80° C. The reaction was carried out under reflux for 4 hours, centrifuged, washed and dried to obtain iron-coated tin dioxide particles, and then calcined in an air atmosphere at 500° C. for 2 hours to obtain ferric oxide-coated tin dioxide particles.

(2)该三氧化二铁包覆的二氧化锡颗粒为核-壳结构，其电镜照片如图2所示。构成核的材料为粒径为20～100nm的二氧化锡，构成壳的材料为三氧化二铁，厚度为10nm；且三氧化二铁均匀包覆在二氧化锡的表面。(2) The tin dioxide particles coated with ferric oxide have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 2 . The material constituting the core is tin dioxide with a particle size of 20-100 nm, and the material constituting the shell is ferric oxide with a thickness of 10 nm; and the ferric oxide is uniformly coated on the surface of the tin dioxide.

实施例3Example 3

制备三氧化二铁包覆的镍钴锰酸锂颗粒Preparation of Fe2O3-Coated Nickel Cobalt Lithium Manganate Particles

(1)将镍钴锰酸锂颗粒0.2g(粒径为1～10μm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的镍钴锰酸锂颗粒，再在700℃氧气气氛下煅烧2h，得到三氧化二铁包覆的镍钴锰酸锂颗粒。(1) Mix 0.2 g of nickel cobalt lithium manganate particles (particle size is 1 to 10 μm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent anhydrous ethanol, under stirring The reaction was carried out under reflux at 80°C for 4 hours, and then centrifuged, washed and dried to obtain iron-coated nickel-cobalt manganate particles, and then calcined at 700°C in an oxygen atmosphere for 2 hours to obtain iron trioxide-coated lithium nickel-cobalt manganate particles. particles.

(2)该三氧化二铁包覆的镍钴锰酸锂颗粒为核-壳结构，其电镜照片如图3所示。构成核的材料为粒径为1～10μm的镍钴锰酸锂，构成壳的材料为三氧化二铁，厚度为5nm；且三氧化二铁均匀包覆在镍钴锰酸锂的表面。(2) The ferric oxide-coated nickel-cobalt lithium manganate particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 3 . The material constituting the core is lithium nickel cobalt manganese oxide with a particle size of 1-10 μm, and the material constituting the shell is ferric oxide with a thickness of 5 nm; and the ferric oxide is uniformly coated on the surface of the lithium nickel cobalt manganate.

实施例4Example 4

制备三氧化二铁包覆的镍钴铝酸锂颗粒Preparation of Fe2O3-Coated Nickel-Cobalt-Lithium Aluminate Particles

(1)将镍钴铝酸锂颗粒0.1g(粒径为1～10μm)、九水硝酸铁0.3g、沉淀剂六次甲基四胺0.3g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的镍钴铝酸锂颗粒，再在700℃氧气气氛下煅烧2h，得到三氧化二铁包覆的镍钴铝酸锂颗粒。(1) Mix 0.1 g of nickel cobalt lithium aluminate particles (particle size is 1 to 10 μm), 0.3 g of ferric nitrate nonahydrate, and 0.3 g of precipitant hexamethylenetetramine in 30 mL of solvent absolute ethanol, and stir under stirring. The reaction was carried out under reflux at 80 °C for 4 hours, and then centrifuged, washed and dried to obtain iron-coated nickel-cobalt aluminate lithium particles, and then calcined at 700 °C in an oxygen atmosphere for 2 hours to obtain ferric oxide-coated lithium nickel-cobalt aluminate. particles.

(2)该三氧化二铁包覆的镍钴铝酸锂颗粒为核-壳结构，其电镜照片如图4所示。构成核的材料为粒径为1～10μm的镍钴铝酸锂，构成壳的材料为三氧化二铁，厚度为25nm；且三氧化二铁均匀包覆在镍钴铝酸锂的表面。(2) The ferric oxide-coated nickel-cobalt lithium aluminate particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 4 . The material constituting the core is lithium nickel cobalt aluminate with a particle size of 1-10 μm, and the material constituting the shell is ferric oxide with a thickness of 25 nm; and ferric oxide is uniformly coated on the surface of the lithium nickel cobalt aluminate.

实施例5Example 5

制备三氧化二铁包覆的钛酸锂颗粒Preparation of Fe2O3-Coated Lithium Titanate Particles

(1)将钛酸锂颗粒0.2g(粒径为50～200nm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的钛酸锂颗粒，再在700℃空气气氛下煅烧2h，得到三氧化二铁包覆的钛酸锂颗粒。(1) Mix 0.2 g of lithium titanate particles (with a particle size of 50 to 200 nm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent anhydrous ethanol, and stir at 80° C. The reaction was carried out under reflux for 4 hours, centrifuged, washed, and dried to obtain iron-coated lithium titanate particles, and then calcined at 700° C. in an air atmosphere for 2 hours to obtain iron trioxide-coated lithium titanate particles.

(2)该三氧化二铁包覆的钛酸锂颗粒为核-壳结构，其电镜照片如图5所示。构成核的材料为粒径为50～200nm的钛酸锂，构成壳的材料为三氧化二铁，厚度为9nm；且三氧化二铁均匀包覆在钛酸锂的表面。(2) The ferric oxide-coated lithium titanate particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 5 . The material constituting the core is lithium titanate with a particle size of 50-200 nm, the material constituting the shell is ferric oxide with a thickness of 9 nm; and the surface of the lithium titanate is uniformly coated with ferric oxide.

实施例6Example 6

制备二氧化锆包覆的二氧化硅颗粒Preparation of zirconia-coated silica particles

(1)将二氧化硅颗粒0.05g(平均粒径为600nm)、五水硝酸锆0.1g、沉淀剂氢氧化锂0.1g在30mL溶剂无水乙醇中混合，在室温下搅拌回流进行反应4h，经离心、洗涤、干燥得到含锆包覆型的二氧化硅颗粒，再在500℃空气气氛下煅烧2h，得到二氧化锆包覆的二氧化硅颗粒。(1) Mix 0.05 g of silica particles (average particle size of 600 nm), 0.1 g of zirconium nitrate pentahydrate, and 0.1 g of lithium hydroxide as a precipitant in 30 mL of solvent absolute ethanol, and stir and reflux at room temperature to react for 4 h, After centrifugation, washing and drying, zirconium-coated silica particles were obtained, and then calcined in an air atmosphere at 500° C. for 2 h to obtain zirconia-coated silica particles.

(2)该二氧化锆包覆的二氧化硅颗粒为核-壳结构，其电镜照片如图6所示。构成核的材料为粒径为600nm的二氧化硅，构成壳的材料为二氧化锆，厚度为28nm；且二氧化锆均匀包覆在二氧化硅的表面。(2) The zirconium dioxide-coated silica particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 6 . The material constituting the core is silicon dioxide with a particle size of 600 nm, and the material constituting the shell is zirconium dioxide with a thickness of 28 nm; and the surface of the silicon dioxide is uniformly coated by the zirconium dioxide.

实施例7Example 7

制备二氧化锆包覆的镍锰酸锂颗粒Preparation of zirconia-coated lithium nickel manganate particles

(1)将镍锰酸锂颗粒0.2g(粒径为1～10μm)、五水硝酸锆0.1g、沉淀剂氢氧化锂0.1g在30mL溶剂无水乙醇中混合，在室温下搅拌进行反应4h，经离心、洗涤、干燥得到含锆包覆型的镍锰酸锂颗粒，再在700℃空气气氛下煅烧2h，得到二氧化锆包覆的镍锰酸锂颗粒。(1) Mix 0.2 g of lithium nickel manganate particles (with a particle size of 1 to 10 μm), 0.1 g of zirconium nitrate pentahydrate, and 0.1 g of lithium hydroxide as a precipitant in 30 mL of solvent absolute ethanol, and stir at room temperature for 4 h. , after centrifugation, washing, and drying to obtain zirconium-coated lithium nickel manganate particles, and then calcined at 700 °C for 2 hours in an air atmosphere to obtain zirconium dioxide-coated lithium nickel manganate particles.

(2)该二氧化锆包覆的镍锰酸锂颗粒为核-壳结构，其电镜照片如图7所示。构成核的材料为粒径为1～10μm的镍锰酸锂，构成壳的材料为二氧化锆，厚度约为45nm；且二氧化锆均匀包覆在镍锰酸锂的表面。(2) The zirconium dioxide-coated lithium nickel manganate particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 7 . The material constituting the core is lithium nickel manganate with a particle size of 1-10 μm, and the material constituting the shell is zirconium dioxide with a thickness of about 45 nm; and the surface of the lithium nickel manganate is uniformly coated by the zirconium dioxide.

实施例8Example 8

一、制备三氧化二铁包覆的镍锰酸锂颗粒1. Preparation of ferric oxide-coated lithium nickel manganate particles

(1)将镍锰酸锂颗粒0.2g(粒径为1～5μm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂无水乙醇中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到含铁包覆型的镍锰酸锂颗粒，再在700℃氧气气氛下煅烧2h，得到三氧化二铁包覆的镍锰酸锂颗粒。(1) Mix 0.2 g of lithium nickel manganate particles (with a particle size of 1 to 5 μm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent absolute ethanol, and stir for 80 The reaction was carried out under reflux for 4 hours, centrifuged, washed, and dried to obtain iron-coated lithium nickel manganate particles, and then calcined at 700 °C in an oxygen atmosphere for 2 hours to obtain iron trioxide-coated lithium nickel manganate particles.

(2)该三氧化二铁包覆的镍锰酸锂颗粒为核-壳结构，其电镜照片如图8所示。构成核的材料为粒径为1～5μm的镍锰酸锂，构成壳的材料为三氧化二铁，厚度为3nm；且三氧化二铁均匀包覆在镍锰酸锂的表面。(2) The ferric oxide-coated lithium nickel manganate particles have a core-shell structure, and the electron microscope photograph thereof is shown in FIG. 8 . The material constituting the core is lithium nickel manganate with a particle size of 1-5 μm, and the material constituting the shell is ferric oxide with a thickness of 3 nm; and the surface of the lithium nickel manganate is uniformly coated with ferric oxide.

二、制备三氧化二铁包覆型的镍锰酸锂电极2. Preparation of Fe2O3-coated LiMnO2 electrode

将步骤一中制备的三氧化二铁包覆的镍锰酸锂颗粒0.2136g、导电添加剂Super P0.0267g、粘结剂PVDF 0.534g与少许溶剂NMP混合均匀，经制浆、涂片(铝片作为集流体)、干燥，得到三氧化二铁包覆型的镍锰酸锂电极。The ferric oxide-coated lithium nickel manganate particles 0.2136g prepared instep 1, the conductive additive Super P 0.0267g, the binder PVDF 0.534g and a little solvent NMP were mixed uniformly. as a current collector), and dried to obtain a ferric oxide-coated lithium nickel manganate electrode.

三、组装电池3. Assemble the battery

以上述制备的三氧化二铁包覆型的镍锰酸锂电极作为正极材料，以金属锂作为负极材料组装成电池。电解液选择浓度为1M的碳酸酯电解液，溶剂为DMC:DEC:EC＝1:1:1(w/w/w)，溶质为LiPF₆。A battery is assembled by using the ferric oxide-coated lithium nickel manganate electrode prepared above as a positive electrode material, and using metallic lithium as a negative electrode material. The electrolyte is selected as carbonate electrolyte with a concentration of 1M, the solvent is DMC:DEC:EC=1:1:1 (w/w/w), and the solute is LiPF₆ .

四、电池测试Fourth, battery test

(1)使用充放电仪对上述电池进行恒流充放电测试，测试电压区间为3～5V，测试温度为25℃。电池容量和充放电电流均以镍锰酸锂的质量计算。(1) Use a charge-discharge instrument to carry out a constant-current charge-discharge test on the above-mentioned battery. The test voltage range is 3-5V, and the test temperature is 25°C. The battery capacity and charge-discharge current are calculated by the mass of lithium nickel manganate.

(2)图9为此材料在0.1C下(0.1C是按理论容量的0.1倍的安培电流进行充放电，对于镍锰酸锂0.1C＝0.1×146.7mAh/g×活性物质的质量)的循环性能。电池在经过100圈循环后，容量为125.5mAh/g(未包覆的镍锰酸锂100圈循环后容量为105mAh/g)，库伦效率在98％以上，具有良好的容量保持率和寿命。(2) Figure 9 shows the material at 0.1C (0.1C is charged and discharged at an ampere current of 0.1 times the theoretical capacity, for lithium nickel manganate 0.1C=0.1×146.7mAh/g×mass of active material) cycle performance. After 100 cycles, the battery has a capacity of 125.5mAh/g (uncoated lithium nickel manganese oxide has a capacity of 105mAh/g after 100 cycles), and the Coulomb efficiency is over 98%, with good capacity retention and life.

对比例1Comparative Example 1

以去离子水为溶剂，制备三氧化二铁包覆的二氧化硅颗粒Preparation of Fe2O3-Coated Silica Particles Using Deionized Water as Solvent

将二氧化硅颗粒0.05g(平均粒径为600nm)、九水硝酸铁0.1g、沉淀剂六次甲基四胺0.1g在30mL溶剂去离子水中混合，在搅拌下80℃回流进行反应4h，经离心、洗涤、干燥得到处理后的二氧化硅颗粒，其电镜照片如图10所示，二氧化硅颗粒表面没有形成包覆层，说明在去离子水中包覆无法成功进行。Mix 0.05 g of silica particles (average particle size is 600 nm), 0.1 g of ferric nitrate nonahydrate, and 0.1 g of precipitant hexamethylenetetramine in 30 mL of solvent deionized water, and reflux at 80 °C for 4 h under stirring. After centrifugation, washing, and drying, the treated silica particles were obtained. The electron microscope photo of the silica particles was shown in Figure 10. No coating layer was formed on the surface of the silica particles, indicating that the coating in deionized water could not be successfully carried out.

对比例2Comparative Example 2

以去离子水为溶剂，制备二氧化锆包覆的二氧化硅颗粒Preparation of Zirconium Dioxide-Coated Silica Particles Using Deionized Water as Solvent

将二氧化硅颗粒0.05g(平均粒径为600nm)、五水硝酸锆0.1g、沉淀剂氢氧化锂0.1g在30mL溶剂去离子水中混合，在室温下搅拌回流进行反应4h，经离心、洗涤、干燥得到处理后的二氧化硅颗粒，其电镜照片如图11所示，二氧化硅颗粒表面没有形成包覆层，说明在去离子水中包覆无法成功进行。Mix 0.05 g of silica particles (average particle size of 600 nm), 0.1 g of zirconium nitrate pentahydrate, and 0.1 g of precipitant lithium hydroxide in 30 mL of deionized water as a solvent, and stir and reflux at room temperature for 4 hours. After centrifugation, washing , and dried to obtain the treated silica particles. The electron microscope photo of the silica particles is shown in Figure 11. No coating layer is formed on the surface of the silica particles, indicating that the coating cannot be successfully carried out in deionized water.

以上，对本发明的实施方式进行了说明。但是，本发明不限定于上述实施方式。凡在本发明的精神和原则之内，所做的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (14)

Translated fromChinese

1.一种金属氧化物的包覆方法，该方法包括如下步骤：在非水溶剂中加入包覆底物材料、金属盐和沉淀剂，得到混合液；所述沉淀剂与金属盐在混合液中反应生成的沉淀均匀沉积在所述包覆底物材料的表面，形成金属氧化物包覆层；1. a coating method of a metal oxide, the method comprising the steps of: adding a coating substrate material, a metal salt and a precipitating agent in a non-aqueous solvent to obtain a mixed solution; the precipitating agent and the metal salt are in the mixed solution The precipitates generated in the reaction are uniformly deposited on the surface of the coated substrate material to form a metal oxide coating layer;所述非水溶剂选自无水有机溶剂，所述无水有机溶剂选自无水醇溶剂和/或无水酮溶剂；所述非水溶剂的纯度为色谱纯级别，其含水量≤0.1wt%；The non-aqueous solvent is selected from anhydrous organic solvents, and the anhydrous organic solvent is selected from anhydrous alcohol solvents and/or anhydrous ketone solvents; the purity of the non-aqueous solvent is chromatographic pure grade, and its water content is less than or equal to 0.1wt %;所述包覆底物材料选自金属、氧化物、碳化物、硫化物、磷化物、氮化物、锂盐、磷酸盐、非金属和有机物颗粒中的至少一种；The coating substrate material is selected from at least one of metals, oxides, carbides, sulfides, phosphides, nitrides, lithium salts, phosphates, non-metals and organic particles;所述金属盐选自硝酸铁或其水合物，硝酸锆或其水合物；The metal salt is selected from ferric nitrate or its hydrate, zirconium nitrate or its hydrate;所述非金属选自选自碳、碳纳米管、石墨烯、氧化石墨烯、富勒烯、硅、磷、硫、硒、碲和硼中的至少一种；The non-metal is selected from at least one selected from carbon, carbon nanotubes, graphene, graphene oxide, fullerenes, silicon, phosphorus, sulfur, selenium, tellurium and boron;所述沉淀剂选自六次甲基四胺、氢氧化锂、氢氧化钠和氢氧化钾中的至少一种。The precipitating agent is selected from at least one of hexamethylenetetramine, lithium hydroxide, sodium hydroxide and potassium hydroxide.2.根据权利要求1所述的金属氧化物的包覆方法，其特征在于，所述金属选自以下金属及其形成的合金中的至少一种：金、银、钯、铂、钌、铑、锡、锗和锑；2. The coating method of metal oxide according to claim 1, wherein the metal is selected from at least one of the following metals and alloys thereof: gold, silver, palladium, platinum, ruthenium, rhodium , tin, germanium and antimony;所述氧化物选自二氧化硅、二氧化锡、三氧化二铝、氧化钼、五氧化二钒、二氧化钛、四氧化三锰、四氧化三钴、二氧化锆、氧化锌、二氧化铈、氧化镁、氧化钙、氧化铟、氧化镓、氧化锂、四氧化三铁和锂镧锆氧中的至少一种；The oxide is selected from the group consisting of silicon dioxide, tin dioxide, aluminum oxide, molybdenum oxide, vanadium pentoxide, titanium dioxide, manganese tetroxide, cobalt tetroxide, zirconium dioxide, zinc oxide, ceria, magnesium oxide, at least one of calcium oxide, indium oxide, gallium oxide, lithium oxide, triiron tetroxide and lithium lanthanum zirconium oxide;所述碳化物选自碳化钙、碳化钛、碳化铬、碳化钒、碳化钨、碳化硅、碳化硼和碳化钽中的至少一种；The carbide is selected from at least one of calcium carbide, titanium carbide, chromium carbide, vanadium carbide, tungsten carbide, silicon carbide, boron carbide and tantalum carbide;所述硫化物选自硫化钼、硫化锌、硫化镍、硫化钴、硫化铋、硫化锡、硫化钨、硫化锑和二硫化钛中的至少一种；The sulfide is selected from at least one of molybdenum sulfide, zinc sulfide, nickel sulfide, cobalt sulfide, bismuth sulfide, tin sulfide, tungsten sulfide, antimony sulfide and titanium disulfide;所述磷化物选自磷化钴、磷化钼、磷化钛、磷化镍、磷化铁和磷化锡中的至少一种；The phosphide is selected from at least one of cobalt phosphide, molybdenum phosphide, titanium phosphide, nickel phosphide, iron phosphide and tin phosphide;所述氮化物选自氮化镓、氮化硼、氮化硅、氮化磷、氮化钨、氮化钒、氮化钛、氮化铌和氮化锂中的至少一种；The nitride is selected from at least one of gallium nitride, boron nitride, silicon nitride, phosphorus nitride, tungsten nitride, vanadium nitride, titanium nitride, niobium nitride and lithium nitride;所述锂盐选自锰酸锂、钴酸锂、镍酸锂、镍锰酸锂、镍锰钴酸锂、镍钴铝酸锂、镍钴酸锂、和钛酸锂中的至少一种；The lithium salt is selected from at least one of lithium manganate, lithium cobaltate, lithium nickelate, lithium nickel manganate, lithium nickel manganese cobaltate, lithium nickel cobalt aluminate, lithium nickel cobaltate, and lithium titanate;所述磷酸盐选自磷酸铁、磷酸钛、磷酸钛锂、磷酸钛铝锂、磷酸铁锂、磷酸钴锂、磷酸锰锂、磷酸锰钴锂、磷酸铁锰锂、磷酸钒锂和磷酸钒钠中的至少一种；The phosphate is selected from iron phosphate, titanium phosphate, lithium titanium phosphate, lithium aluminum titanium phosphate, lithium iron phosphate, lithium cobalt phosphate, lithium manganese phosphate, lithium manganese cobalt phosphate, lithium iron manganese phosphate, lithium vanadium phosphate and sodium vanadium phosphate at least one of;所述有机物颗粒选自酚醛树脂、脲醛树脂、三聚氰胺树脂、聚苯乙烯、聚乙烯吡咯烷酮、聚多巴胺、葡萄糖、壳聚糖和果糖中的至少一种。The organic particles are selected from at least one of phenolic resin, urea-formaldehyde resin, melamine resin, polystyrene, polyvinylpyrrolidone, polydopamine, glucose, chitosan and fructose.3.根据权利要求2所述的金属氧化物的包覆方法，其特征在于，所述氧化物为二氧化硅和/或二氧化锡；3. the coating method of metal oxide according to claim 2, is characterized in that, described oxide is silicon dioxide and/or tin dioxide;所述锂盐选自镍锰酸锂、镍锰钴酸锂、镍钴铝酸锂和钛酸锂中的至少一种。The lithium salt is selected from at least one of lithium nickel manganate, lithium nickel manganese cobaltate, lithium nickel cobalt aluminate and lithium titanate.4.根据权利要求1-2任一项所述的金属氧化物的包覆方法，其特征在于，所述混合液中，包覆底物材料的浓度为0.01~100 g/L，所述金属盐的浓度为1×10^-4~0.1 mol/L，所述沉淀剂的浓度为1×10^-3~1 mol/L。4. The method for coating metal oxides according to any one of claims 1-2, wherein in the mixed solution, the concentration of the coating substrate material is 0.01 to 100 g/L, and the metal The concentration of the salt is 1×10^-4 ~0.1 mol/L, and the concentration of the precipitant is 1×10^-3 ~1 mol/L.5.根据权利要求1-2任一项所述的金属氧化物的包覆方法，其特征在于，所述包覆底物材料的平均粒径为10 nm~20 μm。5 . The method for coating metal oxides according to claim 1 , wherein the coating substrate material has an average particle size of 10 nm to 20 μm. 6 .6.根据权利要求1-2任一项所述的金属氧化物的包覆方法，其特征在于，所述反应的温度为10~100^oC，反应的时间为0.5 h~10 h。6. The coating method of metal oxide according to any one of claims 1-2, wherein the temperature of the reaction is 10～100 ℃, and the time of the reaction is 0.5^h ～10 h.7.根据权利要求1-2任一项所述的金属氧化物的包覆方法，其特征在于，所述方法还包括对含有金属包覆层的金属氧化物进行煅烧处理，得到以金属氧化物为壳的核-壳结构包覆型颗粒；7. The method for coating metal oxides according to any one of claims 1-2, wherein the method further comprises calcining the metal oxide containing the metal coating layer to obtain the metal oxide It is a core-shell structure coated particle with a shell;其中，所述煅烧的气氛为空气、氧气、氮气、氩气、氢气/氩气混合气中的至少一种；Wherein, the calcining atmosphere is at least one of air, oxygen, nitrogen, argon, and hydrogen/argon gas mixture;其中，所述煅烧的温度为400~1000^oC，时间为0.5~10 h。Wherein, the temperature of the calcination is 400-1000^° C, and the time is 0.5-10 h.8.根据权利要求1-7任一项所述的金属氧化物的包覆方法制备得到的以金属氧化物为壳层的核-壳结构包覆型颗粒，所述壳层均匀、连续、完整地包覆在所述包覆底物材料上，且包覆底物材料表面无损；8. Core-shell structure coated particles with metal oxide as shell layer prepared by the coating method of metal oxide according to any one of claims 1-7, the shell layer is uniform, continuous and complete It is coated on the coated substrate material, and the surface of the coated substrate material is not damaged;所述金属氧化物为三氧化二铁、二氧化锆。The metal oxides are ferric oxide and zirconium dioxide.9.根据权利要求8所述的核-壳结构包覆型颗粒，其特征在于，所述壳层的厚度为1-200nm。9 . The core-shell structure-coated particle according to claim 8 , wherein the thickness of the shell layer is 1-200 nm. 10 .10.根据权利要求8或9所述的核-壳结构包覆型颗粒，其特征在于，所述核-壳结构包覆型颗粒为三氧化二铁包覆的二氧化硅、三氧化二铁包覆的二氧化锡、三氧化二铁包覆的镍钴锰酸锂、三氧化二铁包覆的镍钴铝酸锂、三氧化二铁包覆的钛酸锂、三氧化二铁包覆的镍锰酸锂、二氧化锆包覆的二氧化硅或二氧化锆包覆的镍锰酸锂。10. The core-shell structure coated particle according to claim 8 or 9, characterized in that the core-shell structure coated particle is silica, ferric oxide coated with ferric oxide Coated tin dioxide, ferric oxide-coated nickel-cobalt lithium manganese oxide, ferric oxide-coated nickel-cobalt lithium aluminate, ferric oxide-coated lithium titanate, ferric oxide-coated lithium titanate of lithium nickel manganate, zirconium dioxide-coated silica or zirconium dioxide-coated lithium nickel manganate.11.权利要求8-10任一项所述核-壳结构包覆型颗粒在锂电池中的应用。11. Application of the core-shell structure-coated particles according to any one of claims 8-10 in a lithium battery.12.根据权利要求11所述核-壳结构包覆型颗粒的应用，其特征在于，所述核-壳结构包覆型颗粒作为锂电池的正极材料。12 . The application of the core-shell structure-coated particles according to claim 11 , wherein the core-shell structure-coated particles are used as positive electrode materials for lithium batteries. 13 .13.含有权利要求8-10任一项所述核-壳结构包覆型颗粒的锂离子正极材料。13. A lithium ion positive electrode material comprising the core-shell structure-coated particles according to any one of claims 8-10.14.含有权利要求8-10任一项所述核-壳结构包覆型颗粒的锂离子电池。14. A lithium ion battery comprising the core-shell structure coated particles of any one of claims 8-10.

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