| The non renewable nature of petroleum energy and the environmental pollution caused by it have attracted people's attention.Hydrogen energy is a clean,renewable and potential energy.Electrolytic water hydrogen production technology is an efficient way to obtain a large amount of hydrogen,so it is an urgent problem for people to find a high-performance and high-yield electrocatalyst for hydrogen evolution.Some materials with layered structure have attracted more and more attention because of their excellent conductivity and large lithium storage capacity.As a member of these materials,Mo S2 is used as electrocatalyst,electrode material and so on,because of its extreme anisotropy and unique chemical properties.However,the conductivity of block Mo S2 is poor,which greatly affects the electrocatalytic performance.In order to improve this defect,the electrocatalytic properties of Mo S2were improved by calcining,increasing Mo/S ratio and compounding with carbon.The main contents are as follows:With thiourea and sodium thiosulfate pentahydrate as sulfur source,ammonium molybdate tetrahydrate as molybdenum source and oxalic acid as reducing agent,Mo S2 nano tablets were successfully synthesized by hydrothermal method,and then the synthesized Mo S2 nano tablets were calcined at high temperature.Then,X-ray diffraction?XRD?and Raman spectroscopy?Raman?were used the structure,morphology and properties of chips and plates were studied by means of spectrum,SEM and electrochemical test.It was found that calcination had a great influence on the crystal morphology of Mo S2 nano chips.Mo S2 nano chips changed from 2H chips before calcination to 3R plates after calcination.It is found that the electrocatalytic hydrogen evolution performance of calcined samples is much better than that of non calcined samples.Then the influence of the amount of sulfur in the hydrothermal reaction system on the electrocatalytic hydrogen evolution performance of Mo S2 was investigated.The conclusion shows that in the reaction system with molybdate to sulfur ratio of 1:5,the electrocatalytic performance of Mo S2 nano sheet is the best.The sample with sodium thiosulfate pentahydrate as sulfur source has an initial potential of 80 m V after calcination and a Tafel slope of78m V/dec,showing excellent electrocatalytic hydrogen evolution performance.Using glucose as carbon source,thiourea as sulfur source and ammonium molybdate tetrahydrate as molybdenum source,four kinds of Mo S2/C composites were prepared by hydrothermal method and high temperature calcination.The structure,morphology and electrocatalytic properties of four Mo S2/C composites were investigated.The results show that adding 0.5g After calcination,the size of glucose sample increases and it is more dispersed,and the electrocatalytic activity of hydrogen evolution is the best. |
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