Methanol‐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… Click to show full abstract
Methanol‐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).
               
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