Core@Shell Heterostructured NiMoPx@Ni5P4 Nanorod Arrays Promoting Direct Electro‐Oxidation of Methanol and Hydrogen Evolution under Industry Conditions

Abstract

AbstractMethanol‐electrooxidation‐reaction (MOR) to value‐added formate is a promising alternative to water oxidation for cost‐efficient hydrogen production. It is generally proposed that the MOR kinetics on Ni‐based catalysts are highly limited by the transition rate of Ni(OH)2/NiOOH. Yet, how to define the catalyst following the direct pathway without Ni2+/Ni3+ transition remains challenging. Herein, a core@shell heterostructured NiMoPx@Ni5P4 catalyst is developed to selectively promote the MOR at a large current density (> 500 mA cm−2). A series of operando spectroscopic studies reveal negligible formation of NiOOH with 1.0 m methanol in a wide potential range, where MOR is predominant. Theoretical calculations demonstrate that the Ni‐P site of NiMoPx@Ni5P4 favors the adsorption of *CH3OH over *OH while the heterostructure contributes to the significantly reduced energy barrier of *OCH3 →*OCH2, hence promoting the MOR along a direct pathway without the formation of NiOOH. Moreover, further study suggests that the catalyst also performs well toward cathodic hydrogen evolution reaction (HER). As a result, an electrode pair of NiMoPx@Ni5P4//NiMoPx@Ni5P4 is employed to enable concurrent MOR/HER electrolysis at 1.81 V to yield formate/H2 with FEs of ca. 90/100% and long‐term (100‐h) sustainability at 500 mA cm−2 under the industrial conditions (6.0 m KOH, 65 °C).