The Synthesis Of Self-supported Tungsten-based Nanostructures And Their Electrocatalytic Activity In Hydrogen Evolution Reaction

As a clean and renewable resource,hydrogen is viewed as one of the most promising alternative energy.Because the environmental problem and energy crisis become increasing severe,the research concerning sustainable hydrogen generatio n from water splitting is stimulated.Hydrogen evolution reaction?HER?is an uphill reaction,and the electrocatalysts with effective catalytic activity in the HER are essential for efficient water splitting.The highly efficient electrocatalysts should have good electrical conductivity,lager surface area,low hydrogen evolution overpotentia l,good electrochemical stability and corrosion resistance.At present,Pt-group noble metals have been demonstrated as the best HER catalysts,whereas they cannot afford wide range commercial application because of their scarcity and high cost.The development of efficient non-precious HER electrocatalyst remains highly desirable.In this paper,the tungsten/tungsten dioxides?W/WO₂?nanowires array?NA?and the tungsten sulfide?WS₂?nanosheets?NS?were constructed on carbon paper as electrocatalysts for hydrogen evolution reaction.The crystal structures,morphology,and the activity in HER have been studied.Based on the investigation,the research accomplishments are listed as follows:?1?The W/WO₂ NA@CP is synthesized and exhibits efficient catalytic performance in acidic for hydrogen generation.The ?20 is as small as-340 mV vs.RHE in acidic solution.The comparison of theoretical and detected volume of hydrogen during potentiostatic electrolysis confirms that the faradaic efficiency is nearly 100%.Potentiostatic electrolysis and accelerated degradation experiments suggest that W/WO₂ NA@CP can work stably in long term hydrogen generation?54 h?in acidic solution.The W/WO₂ grown on the carbon fiber paper can enable fast electron transport in the electrode.Besides the catalyst is composed of W and WO₂,W can enhances the conductivity of catalyst,while WO₂ can exhibit efficient catalytic activity for hydrogen generation from electrolysis.?2?The WS₂ NS@CP is synthesized by hydrothermal,and exhibits effic ie nt catalytic performance in acidic for hydrogen generation.The ?100 is as small as-209 mV vs.RHE in acidic solution.The comparison of theoretical and detecte d volume of hydrogen during potentiostatic electrolysis confirms that the farad a ic efficiency is 93%.Potentiostatic electrolysis and accelerated degrada t io n experiments suggest that WS₂ NS@CP can work stably in long term hydro ge n generation in acidic solution?25 h?.The EIS measurements suggest that the WS 2 NS@CP has larger electric conductivity,while the electron transfer resistance of the WS₂ NS@CP is relatively smaller.In this study,we produce the WS 2 NS@CP by sulfuration the?NH4?.25WO3 nanowires array.The nanoshee t s catalyst synthesized by sulfuration can provide more reactive edges which is beneficial for its superior performance.The methods introduced here offer new approaches for the design and exploitat io n of nanosheets exhibiting efficient catalytic activity for hydrogen generation from electrolysis.