Oxygen‐Deficient FeNbO_4‐x In‐Situ Growth in Honey‐Derived N‐Doping Porous Carbon for Overall Water Splitting

Abstract

It is still a great challenge to reasonably design green, low cost, high activity and good stability catalysts for overall water splitting (OWS). Here, we introduce a novel catalyst with ferric niobate (FeNbO4) in‐situ growing in honey‐derived porous carbon of high specific surface area, and its catalytic activity is further enhanced by micro‐regulation (oxygen vacancy and N‐doping). From the experimental results and density functional theory (DFT) calculations, the oxygen vacancy in catalyst FeNbO4‐x@NC regulates the local charge density of active site, thus increasing conductivity and optimizing hydrogen/oxygen species adsorption energy. FeNbO4 in‐situ grows within N‐doping honey‐derived porous carbon, which can enhance active specific surface area exposure, strengthen gaseous substances escape rate, and accelerate electrons/ions transfer and electrolytes diffusion. Moreover, in‐situ Raman also confirms O‐species generation in oxygen evolution reaction (OER). As a result, the catalyst FeNbO4‐x@NC shows good electrochemical performance in OER, HER and OWS.