In-situ constructed Ru-rich porous framework on NiFe-based ribbon for enhanced oxygen evolution reaction in alkaline solution

摘要

Exploiting economical and high-efficient electrocatalysts of oxygen evolution reaction(OER)remains urgent in the field of sustainable hydrogen generation by water electrolysis.Ru-and Ir-based materials are benchmark electrocatalysts towards the OER,yet the precious metals are expensive and scarce.Herein,we develop a kind of Ru-doped NiFe-based catalyst with three-dimensional nanoporous surface(NP-Ru_(x)),which fulfils both performance and cost requirements for the OER electrocatalysis.This novel material can directly work as a support-free electrode and exhibits excellent OER performance with an ultralow overpotential of 245 mV at 10 mA cm^(-2) and a small Tafel slope of 15 mV dec^(-1) as well as low charge transfer resistance.The superior performance could be rationalized as follows:(1)Generated Ru-rich nanoporous architecture can not only supply a large number of active sites but also facilitate mass transfer at the electrode/electrolyte interface;(2)Multiple metals(hydro)oxides generated on the surface have the synergistic catalytic effect for the OER;(3)The in-situ generation of(hydro)oxides and the firm bonding of nanoporous layer and the substrate allow for easy electron transfer.These features make NP-Ruxa promising oxygen-evolving electrode material toward water electrolysis.