Sythesis And Electrochemical Properties Of Cobalt Silicate Composites

Energy crisis has become a global serious issue in recent years.In the 13th Five-Year Plan of China,specific requirements about the development of energy storage and new materials have been put forward for several times and included in the future plan to implement major projects.It fully demonstrates that the progress of energy storage equipment and new materials related has been highly concerned.As a new kind of energy storage device in recent years,supercapacitor has been regarded as a new ideal energy storage device due to its advantages such as high capacity,high stability,long cycle life and high safety.Electrode materials with the properties of high capacity,high power density,long cycle life and environmental-friendly,have been concerned as an important issue in energy storage field,for their electrochemical properties determine the capacitors performance.Cobalt silicate(Co2SiO4)as a kind of transition metal silicate,has the original characteristics of silicate,such as stable structure,non-toxicity and electrochemical performance,has gradually become a hot spot in the field of electrode materials research.However,cobalt silicate also has obvious weaknesses such as weak conductivity,low specific capacitance,etc.In view of the above problems,the main purpose of this paper is to improve the electrochemical performance of cobalt silicate materials while retaining its original advantages via different ways such as compounded and modified.In this paper,a series of supercapacitor electrode materials based on cobalt silicate are designed and synthesized with optimizing the structure and non-metallic doping method to improve their electrochemical performance.The main contents are as follows:(1)Co2SiO4@Ni(OH)2 with core-shell structure was prepared based on amorphous Co2SiO4 nanobelts by a hydrothermal facile route.The electrochemical property of the composite had been improved by compounded with Ni(OH)2 and modified the structure.(2)Co2SiO4@MnO2 with core-shell structure was prepared for the reason of MnO2 with large operating voltage intervals.The electrochemical property of the composite was much higher than Co2SiO4 nanobelts.(3)A new kind of binary material[Co2SiO4@Co(OH)2]was synthesized by a facile route.Using the long cycle life characteristic of Co(OH)2,the electrochemical property of the composite had been improved obviously.(4)P-doped Co2SiO4 was synthesized by nonmetallic doping method.The effect of phosphating reaction on the structure of Co2SiO4 nanobelts and main factors of improving its electrochemical performance were discussed.