| As the world’s population continues to grow,so does the demand for energy.As a pillar of today’s energy supply,fossil fuels are constantly exploited and used up,and their emissions pollute the environment seriously in the process of use.The contradiction between energy demand and environmental demand has become a crucial issue.Hydrogen energy has the characteristics of high calorific value and environmental protection.If hydrogen energy can be developed rapidly,this contradiction can be solved,but the obstacle to the development of hydrogen is the production of hydrogen.Electrolysis of water to produce hydrogen is considered to be the most environmentally friendly and effective way to produce hydrogen,but the high price of electrocatalyst hinders the development of electrolysis of water.Transition metal sulfide Mo S2 has attracted extensive research interest due to its stable chemical properties.Up to now,there are many ways to synthesize Mo S2 nanosheets.The common synthesis methods include mechanical stripping,chemical vapor deposition,thermal solvent,etc.In this paper,molten salt electrochemical method will be used to prepare Mo S2,and by doping non-precious metals（Nb,Cu,Co）to increase the crystal defects of Mo S2 nanosheets,so that they expose more edge active sites,and improve the electrocatalytic performance.Its main contents are as follows:Two kinds of morphology of Nb/Mo S2 were successfully prepared by adding Nb Cl5 into the molten salt system preparing Mo S2.The petal-like Nb/Mo S2 had better electroexcitation effect in 1 mol/L KOH:the overpotential was 292.9 m V at the current density of 10 m A/cm2;Tafel slope was 107 m V/dec;The double layer capacitor size was 34.5 m F/cm2;at the same time with the smallest 15Ωequivalent charge transfer resistance(RCT).Compared with molybdenum disulfide without Nb,it showed better HER activity and good stability.The two morphologies of Cu/Mo S2 in electrolytic water reaction are as follows:petal-like Cu/Mo S2 in 1 mol/L KOH electroexcitation effect was better,the current density of 10 m A/cm2overpotential was 269.7 m V;tafel slope was 165.3 m V/dec;the double layer capacitance was41.8 m F/cm2;and it has the smallest charge transfer equivalent resistance(RCT)6.25Ω.Mo S2 was modified by different amount of Co,the electrocatalytic effect of Mo S2 doped with 14%Co in 1 mol/L KOH is as follows:the overpotential is 229.2 m V at a current density of 10 m A/cm2,tafel slope was 195 m V/dec,double layer capacitance size 19.6 m F/cm2,also has the smallest 3.6Ωequivalent charge transfer resistance(RCT).This study provides a new preparation idea for the development and design of electrocatalysts for non-precious metal compounds.In this paper,a new idea of transition metal doped nanocomposite hydrogen evolution electrode was designed by molten salt electrolysis,and combined with a variety of electrochemical research techniques,the synergistic enhancement mechanism of electrocatalytic hydrogen evolution of transition metal doped Mo S2 was revealed,which provides technical support and theoretical guidance for hydrogen production by electrolysis of water with low energy consumption and high efficiency. |
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