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Metallene is considered as an emerging family of electrocatalysts due to its atomically layered structure and unique surface stress. Here we propose a strategy to modulate the Bader charge transfer (BCT) between Pd surface and oxygenated intermediates via p‐d electronic interaction by introducing single‐atom p‐block metal (M=In, Sn, Pb, Bi) into Pd metallene nanosheets towards efficient oxygen reduction reaction (ORR). X‐ray absorption and photoelectron spectroscopy suggests that doping p‐block metals could facilitate electron transfer to Pd sites and thus downshift the d‐band center of Pd and weaken the adsorption energy of O intermediates. Among them, the developed Bi−Pd metallene shows extraordinarily high ORR mass activity of 11.34 A mgPd−1 and 0.86 A mgPd−1 at 0.9 V and 0.95 V in alkaline solution, respectively, representing the best Pd‐based ORR electrocatalysts ever reported. In the cathode of a Zinc‐air battery, Bi−Pd metallene could achieve an open‐circuit voltage of 1.546 V and keep stable for 760 h at 10 mA cm−2. Theoretical calculations suggest that the BCT between Pd surface and *OO intermediates greatly affects the bond length between them (dPd‐*OO) and Bi doping could appropriately reduce the amount of BCT and stretch the dPd‐*OO, thus enhancing the ORR activity. [ABSTRACT FROM AUTHOR]

The stability of Pt‐based catalysts for oxygen reduction reaction (ORR) in hydrogen fuel cells is seriously handicapped by the corrosion of their carbon supports at high potentials and acidic environments. Herein, a novel SnS2/SnO2 hetero‐structured support is reported for Pt nanoparticles (NPs) as the ORR catalyst, where Pt NPs are mainly deposited at the interfaces of SnS2 and SnO2 moieties. The Pt‐support interactions, which can be tuned by the concentration of the heterointerfaces, can accelerate the electronic transfer and enrich the electron density of Pt with a favorable shift of the d‐band center. In electrochemical measurements, the ORR mass activity (MA) of the optimal Pt‐SnS2/SnO2 catalyst at 0.9 V versus RHE (0.40 A mgPt−1) is four times higher than that of Pt/C. As for the stability, the electrochemical active surface area and MA of Pt‐SnS2/SnO2 are only decreased by 18.2% and 23.7% after 50 000 potential cycles at a high potential region (1.0–1.6 V), representing the best ORR stability among the reported Pt‐based catalysts. Density functional theory calculations indicate that the binding energy and migration barrier of Pt atom/cluster on the SnS2/SnO2 heterojunction are much higher relative to other supports, accounting for the outstanding stability of the catalyst. [ABSTRACT FROM AUTHOR]