Preparation And Electrocatalytic Performance Of Transition Metal Phosphides Micro/Nano Hierarchical Arrays

Precious metal-based catalysts such as Pt/C,IrO₂ and RuO₂ are generally regarded as superior electrocatalysts.But scarce resources and high costs have limited their development.Therefore,the search for low-cost and high performance non-noble metal catalysts to replace precious metal catalysts has become a research hotspot in recent years.Although many researchers have made tremendous contributions,developing low-cost,highly active and stable bifunctional electrocatalysts is still a challenging issue in water splitting.The electrocatalysts based on transition metal phosphides（TMPs）featured with good conductivity,fast charge transfer and high reaction kinetics,exhibit good bifunctional electrocatalytic properties.Designing electrocatalysts through structural and compositional engineering is an effective strategy to enhance catalytic activities as well as durability.In this paper,TMPs catalysts with micro/nano hierarchical structures were prepared on the Ni foam by rational design,and the morphology,structure and electrocatalytic performance of the products were studied.The main research contents are as follows:1.We report the fabrication of heterostructured P-Co MoO₄@NiCoP arrays on nickel foam substrate through effective interface engineering,by adjusting its composition and architecture.The P-Co MoO₄@NiCoP/NF arrays with heterostructure can be coordinated to boost the overall water splitting because of the tailored electronic structure and exposed active sites.Therefore,the heterostructured P-Co MoO₄@NiCoP/NF exhibits superior bifunctional electrocatalysis activities with low overpotential of 66 m V at 10 m A cm^-2 for HER and 252 m V at 100 m A cm^-2 for OER,respectively.And only 1.62 V cell voltage is required to deliver 20 m A cm^-2 in a two-electrode electrolysis system,exhibiting excellent overall water splitting performance.The rational construction of heterostructure provide the possibility to purposefully regulate the electronic structures and active sites of electrocatalysts for promoting their catalytic activities.2.A novel porous NiCoP multistage micro-nano structure array was designed and fabricated by hydrothermal co-precipitation method based on nickel foam substrate.The NiCoP arrays have a large specific surface area and expose abundant active sites due to the unique lamellar nanosheet cross morphology and the porous structure formed after phosphating.Therefore,they can promote overall water splitting and exhibit excellent catalytic performance in alkaline solution.In 1.0 M KOH electrolyte,when the current density is 20 m A cm^-2,the potential for overall water splitting is only 1.70V,exhibiting excellent dual-function electrocatalysts.