Pd Embedded in 1T‐Rich MoS 2 With Island‐Sea Confinement for C 2 ‐Selective Ethanol Electrooxidation
Xiaowen Gu, Yu Liang, Pengcheng Zhao, Xinye Zhang, Wei Liu, Chenyu Cui, Zihao Xing, Shangqian Zhu, Jinfa ChangABSTRACT
Direct ethanol fuel cells (DEFCs) are hampered by sluggish C─C bond cleavage and CO poisoning during ethanol electrooxidation on Pd catalysts. Selective oxidation to acetate through the C 2 pathway circumvents CO formation, yet achieving near‐exclusive C 2 selectivity remains challenging. Herein, we report a nitrogen‐doping‐induced expansion strategy that converts bulk 2H‐MoS 2 into a metastable 1T‐rich MoS 2‐x support (NTMS x ) with enlarged interlayer spacing and abundant sulfur vacancies. Conductive 1T domains preferentially anchor Pd nanoparticles, creating an “island‐sea” architecture that fosters pronounced electronic metal‐support interaction (EMSI). Electron transfer from NTMS x to Pd generates electron‐rich Pd sites that weaken CO adsorption, while sulfur vacancies enhance hydroxyl adsorption. These synergistic effects steer ethanol electrooxidation toward the C 2 ‐4e pathway and suppress CO formation. DFT calculations confirm favorable energetics for the C 2 pathway on Pd/NTMS x . The catalyst delivers a high current density and 95.7% Faradaic efficiency for acetate of high added value, with no detectable CO intermediates and outstanding durability. In DEFCs, it achieves a maximum power density of 0.68 W cm −2 and operates stably for over 500 h. This work establishes confined interfacial anchoring on phase‐engineered metal dichalcogenides as a rational design principle for achieving high pathway selectivity in multielectron electrocatalysis.