Construction And Hydrogen Evolution Performance Of Carbon-coated Doped Noble Metal Electrocatalysts

Environmental pollution caused by the consumption of traditional fossil energy and its products has attracted much attention.It is urgent to find clean and sustainable new energy alternatives to traditional fuels.As a strategic reserve energy source in the 21st century,hydrogen energy is favored for its zero pollution,recycling and high energy density.As one of the hydrogen production methods,electrolytic water has the characteristics of rich raw materials,high product purity and easy control of reaction conditions,and has a very wide application prospect.This paper has successfully prepared a carbon-coated doped precious metal electrocatalyst material,and applied it to the hydrogen precipitation reaction（HER）within the full p H range.The main exploration contents are as follows:1.Rh-based catalysts can be used as a substitute for Pt-based catalysts to catalyze HER reaction in the full p H range,but the content of Rh in these catalysts is still high and less stable.Therefore,we should construct heteroatomic doping to reduce the load of Rh and improve the stability of Rh-based materials.The results show that the ultrafine P-modified Rh nanoparticles embedded in N and P-doped ultrathin carbon layers can jointly improve the HER activity of Rh-P@NPC in the full p H range,and the overpotential is much smaller,requiring only 31 m V,65 m V and 130 m V to obtain a current density of 10 m A cm^-2 with excellent stability.On the one hand,its good electrocatalytic performance comes from the synergistic effect of the doped metal core and the carbon layer.On the other hand,the surface carbon shell can protect the inner metal core from the corrosion and agglomeration of the electrolyte to accommodate the harsh electrocatalytic processes.Therefore,the construction of heteroatom-doped ultrathin carbon layers to encapsulate Rh-based nanoparticles provides a feasible strategy for the preparation of highly active and stable catalysts for hydrogen evolution in water electrolysis.2.The key to the development and transformation of renewable energy is to rationally design nanostructures with good activity and stability and realize stable and efficient hydrogen production.Rh@BNC carbon nanospheres with excellent catalytic properties were synthesized through an organic-inorganic pyrolysis reduction strategy.The prepared Rh@BNC carbon nanospheres exhibited excellent HER activity,driving a current density of 10 m A cm^-2 with only a low overpotential of 42 m V,and exhibited good durability.The high specific surface area of the Rh@BNC carbon nanosphere and the presence of the mesoporous structure can promote the full diffusion of the reactants between the electrocatalyst and the electrolyte,and better enhance the hydrogen precipitation performance in the full p H range.At the same time,NBC carbon layer protects Rh nanoparticles from oxidation and corrosion in harsh HER environment,so that the catalyst has good durability.