Preparation Of Co-based Non-noble Metal Catalyst And Its Catalytic Performance In Electrolytic Water

The energy crisis and environmental pollution caused by the extensive use of traditional non-renewable energy are becoming more and more serious,which makes it imperative to explore and develop new clean renewable energy.Among the many renewable energy sources,hydrogen energy is considered to be the most potential substitute for fossil fuel in the future because of its abundant reserves and clean and pollution-free characteristics.Electrolytic water hydrogen production technology is one of the most promising hydrogen production methods because of its simple hydrogen production process and wide sources of raw materials.However,due to the slow kinetics of anodic oxygen evolution reaction（OER）and high overpotential,the overall efficiency of hydrogen production technology by electrolysis of water is still relatively low.Therefore,in order to improve the overall reaction efficiency of electrolytic water,it is necessary to study electrolytic water catalyst and reduce OER overpotential.Oxides based on the precious metals Ru and Ir（such as RuO₂ and IrO₂）are considered to be the most effective catalysts for OER in alkaline solutions,but their low reserves,high price and low stability at high potentials hinder their practical application.At present,the catalytic performance of the fourth cycle transition group catalytic materials of OER has been concerned.For example,Co-based catalyst is widely used as the active material of OER because of its acceptable activity,high durability and relatively low cost.In this paper,a simple electrochemical deposition method is used to rapidly prepare carbon-free and non-adhesive Co-based non-precious metal catalysts(Co,Co_xCu_1-x and Co_xNi_1-x alloy catalysts)on clean glassy carbon sheets,and they are characterized by XRD,SEM,TEM,EDS and XPS.Then the electrochemical workstation was used to test their performance of oxygen evolution from water in 0.1 M KOH electrolyte.The main research contents and conclusions are as follows:（1）The catalytic performance of the catalyst can be regulated by regulating the deposition voltage and electrodeposition liquid concentration of Co catalyst.The OER catalytic performance of Co catalyst can be increased to a certain extent by increasing the deposition current and depositing more catalysts.However,when the Co catalyst content increases to a certain extent,it has no significant effect on the on the improvement of catalytic performance.（2）In a series of Co_xM_1-x（M=Cu,Ni）alloy catalysts,Co_0.7Cu_0.3 and Co_0.6Ni_0.4 alloy catalysts obtained by screening and optimization showed good OER activity.Among them,the mass activity of Co_0.7Cu_0.3 alloy catalyst was comparable to that of RuO₂ and other CoCu-based electrocatalysts.The experimental results show that Co_xM_1-x alloy catalyst will be oxidized to produce new active substances such as CoO and NiO during the reaction,which has a positive effect on its good long-term stability.（3）In Co_xM_1-x（M=Cu,Ni）alloy catalyst,the alloying and composition regulation of Co and M can realize the regulation of the electronic structure of the catalyst and the shift control of the d-band center,which has a positive effect on improving the activity and durability of Co_xCu_1-x alloy catalyst.