Preparation Of Mo-based Catalyst And Its Hydrogen Precipitation Performance

In the recent,with the growing energy crisisis,Human demand for clean and renewable energy development is becoming more and more urgent.Among various sources of alternate energy,hydrogen energy has been attracting extensive attention since it is a new powerful,clean fuel source.As one of the effective ways to produce hydrogen,Electrolysis of water hydrogen evolution technology has attracted people's attention.Therefore,development of abundant,cheap and effective electric catalyst of hydrogen evolution have become the focus of the scientific workers in recent years.Especially,Sulfide,nitride,carbide of group VIB metals have excellent corrosion resistance,high mechanical strength and stability,and a higher melting point.Among these homologous metals,Mo-based compounds have better catalytic activity for catalytic hydrogen evolution.The molybdenum precursor was synthesized by using ammonium molybdate as molybdenum source and tartaric acid as reducing agent.The MoS2 catalyst was prepared by pulverizing the molybdenum precursor with thiourea as the sulfur,calcined at different temperatures.Electrochemical analysis of hydrogen test results shows that:The difference in calcination temperature leads to the difference in morphology,crystallinity,conductivity,and reactive sites of the synthesized catalyst.The experimental results show that the catalytic performance of 3Mo8S-450 catalyst is best produced under 450 ? calcination.The initial voltage is only 50 mV and overvoltage is only 160 mV when the current density is 10 mA · cm-2.Tafel slope is 84 mV · dec-1,which shows 450 ? synthesis of the catalyst has the best catalytic hydrogen catalytic activity.The molybdenum precursor was synthesized by using ammonium molybdate as molybdenum source and tartaric acid as reducing agent.Nickel-doped molybdenum sulfide MoSx-Ni was synthesized by hydrothermal synthesis at 20 ? using thiourea as sulfur source and nickel acetate as nickel source.The effects of adjusting the ratio of thiourea and precursor and the effect of the addition of nickel acetate on the product were discussed.In particular,the effect of adjusting the amount of nickel acetate on the active sites in MoSx-Ni was discussed.The results show that the hydrogen evolution of the product is the best when the mass ratio of precursor and thiourea is 1:4.MoSx-Ni-2 prepared with the addition of nickel acetate at the concentration of 1:4 had the best catalytic activity for hydrogen evolution.The starting voltage is only 50 mV;the overvoltage is only 240 mV at a current density of 10 mA ·cm-2;the tafel slope is 78.8 mV · dec-1.The molybdenum precursor was synthesized by using ammonium paramolybdate' as molybdenum source,tartaric acid as reducing agent and carbon dioxide as a carbon source,respectively.MoO2 catalytic with carbon loaded material was produced by hydrothermal synthesis at different temperatures.The effects of adjusting the mass ratio of glucose and precursors and the effects of different hydrothermal temperatures on the product were discussed.The results show that MoO2/C-550 prepared at a hydrothermal temperature of 550 ? has the best catalytic activity for hydrogen evolution at the mass ratio of 1:4(molybdenum precursor:glucose).The starting voltage is only 198 mV;the overvoltage is only 280 mV at a current density of 10 mA ·cm-2;the tafel slope is 85 mV·dec-1.