Preparation, Photocatalytic And Electrochemical Properties Of Germanium Germanate Nanocomposites

With the continuous development and progress of the social economy,many problems require people's attention and solutions.As a wide bandgap semiconductor,Zn₂GeO₄ has very important research value for solving energy crisis and water pollution problems.As a photocatalyst,Zn₂GeO₄ can effectively degrade organic contaminants in water under light irradiation.It is a good water treatment material,but its absorption and utilization of light is only in the ultraviolet range,which limits its application in terms of water treatment.Zn₂GeO₄ as a negative electrode material for sodium ion battery alloys has a high theoretical capacity for storing sodium sodium is stored?according to NaGe form?.The research is of great significance.However,the poor cyclicity is a serious problem,and it is caused by the large volume change when sodium ion entry and exitit the negative electrode.This problem hinders the development of Zn₂GeO₄ in the field of sodium-ion batteries.This article addresses the above issues,according to the methods of constructing heterojunction,carbon material coating,the performance of Zn₂GeO₄ material is significantly improved in photocatalytic and sodium ion battery applications.The p-BiOBr/n-Zn₂GeO₄ heterojunction materials were prepared by a two-step method?hydrothermal method and solvothermal method?.The photocatalytic degradation of rhodamine B shows that the reaction conditions for photocatalytic degradation of organic materials have extended from ultraviolet to visible light.The light trapping experiments and the characterization of various tests showed that h⁺and O₂^·-played a leading role in the photocatalytic process,and·OH radicals had almost no effect.In the second step when preparing materials?solvent thermal reaction?,BiOBr/Zn₂GeO₄ composites with different morphologies were prepared using water,ethylene glycol,and ethylene glycol monomethyl ether as solvents.The results of photocatalytic evaluation show that the micro-morphology of the material has a great influence on the photocatalytic performance.The photocatalytic performance of the sea cucumber-like BiOBr/Zn₂GeO₄ heterojunction material prepared with ethylene glycol monomethyl ether as solvent is the best.Finally,PDA-Zn₂GeO₄ precursor was prepared at room temperature using dopamine hydrochloride as a carbon source,and Zn₂GeO₄@C composite was prepared by the method of high temperature thermal reduction.The electrochemical test of the assembled sodium-ion battery shows that the material has excellent charge-discharge cycle performance and good rate performance compared with that before the modification.