Preparation And Catalytic Hydrogen Evolution Performance Of CoNiS Based Catalyst

Developing a renewable green energy to replace fossil fuels becomes an important topic in the field of environment and energy with the increasing energy crisis and environmental problems.Great attention has been focused on hydrogen as a potential energy vector.The water-splitting technology is a clean and renewable means to generate hydrogen by using catalysts to convert other forms of energy.Pt,Ru and other metals and their oxides are commonly used as catalysts for water splitting,but the high cost and resource scarcity limit their large-scale application.Thus,it is of great significance to develop non-noble metal catalysts with high catalytic activity for hydrogen production from water splitting.In this paper,CoNiS based materials were studied for the application of electrocatalysts and photocatalysts for hydrogen production.This study will provide the knowledge of developing high efficient non-noble metal catalysts for hydrogen production.1.CoNi alloy films were first prepared on carbon cloth substrates by magnetron sputtering,and then the CoNiS electrodes were fabricated by the high temperature vulcanization method.In order to explore it as a co-catalyst for photocatalytic hydrogen production,the activity and stability for electrocatalytic hydrogen evolution of the CoNiS electrodew were studied.Compared with the CoS electrode,CoNiS exhibit the higher activity and stability for electrocatalytic hydrogen evolution.It is required a potentialof253 mV for the CoNiS electrodes to reach the current density of 10 mA/cm²,and the taffel slope is 54 mV/dec.It is shown that no obvious degradation of catalytic hydrogen evolution activity was observed for the CoNiS electrode after 1000 cycles,indicating it as a high active non-noble metal catalyst for hydrogen production.2.CoNiS is prepared by the MOF precursor,and is used as the co-catalyst of TiO₂ for photocatalytic hydrogen production.The effects of the content of MOF,the treating temperature and the Co/Ni ratio on the structure and photocatalytic hydrogen production performance of TiO₂@CoNiS hybrid materials are studied.When the content of MOF is0.2 at.%,the teat temperature is 600?,and the Co/Ni ratio is 1:1,TiO₂@CoNiS hybrid material exhibits the highest photocatalytic activity.Its photocatalytic hydrogen production rate?1.29 mmol/h/g?is 64.5 times higher than that of the pristine TiO₂,even higher than that of the commercial P25.Based on the analysis of the relationship between the microstructure,chemical composition,light response characteristics of the hybrid materials and their photocatalytic hydrogen productionrate,combinedwith the electrocatalytic hydrogen production performance of CoNiS co-catalysts,the process and mechanism of TiO₂@CoNiS for photocatalytic hydrogen production were clarified.