Dealloying‐Induced Electronic Structure Engineering and Interfacial Microenvironment Optimization for Efficient Ammonia Oxidation

ABSTRACT The sluggish kinetics of the ammonia oxidation reaction (AOR) severely hamper the development of ammonia‐based energy technologies, demanding the rational design of highly efficient electrocatalysts. Herein, we develop a dealloyed PtIrNi single‐atom alloy catalyst supported on a phosphorus‐doped Co‐N‐C substrate (E‐Pt 3 Ir 0.8 Ni 0.2 /Co‐NPC) through an integrated atomic‐scale engineering strategy. Experimental studies combined with density functional theory calculations reveal that isolated Ni atoms embedded in the PtIr framework induce local charge redistribution and a downshifted Pt d‐band center, thereby weakening the excessive adsorption of poisonous N* intermediates and facilitating key dehydrogenation steps. Meanwhile, asymmetric Co‐N 3 ‐P sites promote OH adsorption, and the enhanced metal‐support interaction further facilitates the formation of a strongly hydrogen‐bonded interfacial water network, thereby enabling rapid OH − transport at the catalyst/electrolyte interface. Owing to the synergistic regulation of the metallic active phase and interfacial microenvironment, E‐Pt 3 Ir 0.8 Ni 0.2 /Co‐NPC delivers a mass activity (MA) of 154.1 A g Pt −1 and a specific activity (SA) of 0.236 mA cm ECSA −2 , which are 2.6 and 2.4 folds of those for commercial Pt/C, respectively. This work highlights a general strategy for boosting complex multistep electrocatalysis through coupled single‐atom alloy engineering and interfacial microenvironment regulation.