Electronically Double‐Layered Metal Boride Hollow Nanoprism as an Excellent and Robust Water Oxidation Electrocatalysts

Abstract

Metal–metalloid compounds have been paid much attention as new high‐performance water oxidation catalysts due to their exceptional durability for water oxidation in alkaline media originating from the multi‐dimensional covalent bonding of the metalloid with the surrounding metal atoms. However, compared to the excellent stability, a relatively low catalytic activity of metal‐metalloids often limits their practical application as high‐performance water oxidation catalysts. Here, for the first time, disclosed is a novel self‐templating strategy combined with atomic layer deposition (ALD) to design the electrochemically active and stable quaternary metal boride (vanadium‐doped cobalt nickel boride, VCNB), hollow nanoprism by inducing electronic double layers on the surface. The incorporation of V in a double‐layered structure can substantially increase the number of surface active sites with unsaturated electronic structure. Furthermore, the induced electronic double layers of V can effectively protect the dissolution of the surface active sites. In addition, density functional theory (DFT) calculations reveal that the impressive water oxidation properties of VCNB originate from the synergetic physicochemical effects of the different metal elements, Co and B as active sites, Ni as a surface electronic structure modifier, and V as a charge carrier transporter and supplier.

Metal Boride‐Based Catalysts for Electrochemical Water‐Splitting: A Review

“…In case of HER, this metric works well and gives a good comparison of the state‐of‐the‐art materials. However, being a multistep reaction, OER is often accompanied by oxidation of the catalytic species to produce intermediates, giving rise to a huge oxidation wave, spanning from a few µA cm −2 to tens of mA cm −2 . In such cases, the metric of 10 mA cm −2 is used precariously, leading to overestimated performances.…”

“…The optimized quaternary catalyst showed impressive OER rate (η 10 = 274 mV) in 1 m KOH (Figure c,d). Recently, a quaternary alloy of vanadium doped cobalt nickel boride (VCNB) was developed in the form of hollow nanoprisms . When the catalyst was supported on Ni foam, an overpotential of only 280 mV was required to achieve 30 mA cm −2 in 1 m KOH, demonstrating the combined advantages of metal incorporation, nanostructuring and porous metal foam.…”

Nanostructured core–shell metal borides–oxides as highly efficient electrocatalysts for photoelectrochemical water oxidation

“…Conventionally, nanostructured metal boride catalysts are synthesized by the chemical reduction of metal salt precursors with NaBH 4 . 3,22 An additional annealing treatment is usually necessary if crystalline structures need to be obtained. 16 From the practical application perspective for this kind of catalysts, more simple, cost-efficient, high-yield synthetic routes are preferred, for amenable mass production while enabling sufficient active sites.…”

Nitrogen Engineering on 3D Dandelion‐Flower‐Like CoS2 for High‐Performance Overall Water Splitting

“…Nevertheless, their widespread applications are severely limited by their high cost and scarcity. To this end, tremendous efforts have been devoted to develop highly efficient and cost‐effective electrocatalysts, such as transition metal oxides, selenides, borides, phosphides, nitrides, carbides, and sulfides . However, catalysts both used for OER and HER in the same electrolyte for water electrolysis taking the advantages of both simplifying the system and reducing the cost, usually suffer from low stability and inferior performance, which greatly impede their practical applications as bifunctional electrocatalysts.…”