Synthesis Of Cobalt And Nickel Based Sulfide (Phosphide) Hybrid Electrocatalysts And Their Electrocatalytic Performance For Oxygen Evolution Reaction

The imminent environmental pollution resulting from fossil fuel consumption has greatly motivated substantial research efforts for developing clean energy fuels.Hydrogen,with advantages of little pollution and high efficiency,is regarded as ideal candidate to replace fossil fuels.Comparing with catalytic steam reforming reaction,the electrochemical water splitting provides a promising method for large-scale hydrogen production,since it could effectively make use of the intermittent electricity generated by renewable energy and has advantages of rich source of water and low carbon emission.However,the anodic overpotential severly hinders the hydrogen production efficiency by water electrolysis.In addition,compared with basic OER,the acidic OER possesses higher ionic conductivity and fewer side reactions,which is more suitable for the process of OER.Neverthless,catalysts capable of sustained oxygen production in strongly acidic soutions have been exclusively to limited choices.The most active catalysts for OER are Ir and Ru based compounds,however,they suffer from high cost and scarcity.Therefore,it is highly attractive to explore and develop efficient electrocatalyst made of earth-abundant materials.It's feasible to synthesize transition metal oxide and its morphology is easy to control.Therefore,the activity of transition metal oxide can be improved by metal doping and construction of unique structure.But the catalytic performance of transition metal oxide is severely limited by its low conductivity.Furthermore,cobalt and nickel-based sulfide(phosphide)hybrid electrocatalysts is synthesized for their higher conductivity.Therefore,the metal doping and constructing of unique structure have been adapted to obtain electrocatalysts with superior activity.Herein,the metal doping and constructing nanostructure are directly used as promising methods to synthesize active electrocatalysts.In addition,the internal connection between metal doping and nanastructuring and activity have also been systematically studied,which would provide theoretical basis for furture synthesis of highly active OER electrocatalysts.(1)In order to improve the activity of cobalt and nickel based oxideselectrocatalysts,the doping of Ag offers an opportunity to get mesoporous nanorod and to use cobalt oxides as active electrocatalyst for acidic OER,the method of Fe doping and constructing hybrid structure has been adopted to construct efficient cobalt nickel oxides electrocatalyst,which would provide theoretical basis for the synthesis of active cobalt and nickel based sulfide(phosphide)electrocatalysts.(2)The constructing of binary metal sulfides and designing novel nanorod arrays have been adopted to improve the activity of cobalt nickel based sulfide electrocatalysts.(3)The doping of Ag,Fe and designing novel nanosheet arrays have been used to boost the catalytic performance of cobalt based phosphide electrocatalysts.