Lacking strategies to simultaneously address the intrinsic activity, site density, electrical transport, and stability problems of chalcogels is restricting their application in catalytic hydrogen production. Herein, we resolve these challenges concurrently through chemically activating the molybdenum disulfide (MoS2) surface basal plane by doping with a low content of atomic palladium using a spontaneous interfacial redox technique. Palladium substitution occurs at the molybdenum site, simultaneously introducing sulfur vacancy and converting the 2H into the stabilized 1T structure. Theoretical calculations demonstrate the sulfur atoms next to the palladium sites exhibit low hydrogen adsorption energy at –0.02 eV. The final MoS2 doped with only 1wt% of palladium demonstrates exchange current density of 805 μA cm−2 and 78 mV overpotential at 10 mA cm−2, accompanied by a good stability. The combined advantages of our surface activating technique open the possibility of manipulating the catalytic performance of MoS2 to rival platinum.

Great enthusiasm in single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) has been aroused by the discovery of M−N X as a promising ORR catalysis center. However, the performance of SACs lags far behind that of stateof-the-art Pt due to the unsatisfactory adsorption−desorption behaviors of the reported catalytic centers. To address this issue, rational manipulation of the active site configuration toward a well-managed energy level and geometric structure is urgently desired, yet still remains a challenge. Herein, we report a novel strategy to accomplish this task through the construction of an Fe−Co dual-atom centered site. A spontaneously absorbed electron-withdrawing OH ligand was proposed to act proactively as an energy level modifier to empower easy intermediate desorption, while the triangular Fe−Co−OH coordination facilitates O−O bond scission. Benefiting from these attributes, the as-constructed FeCoN 5 −OH site enables an ORR onset potential and half-wave potential of up to 1.02 and 0.86 V (vs RHE), respectively, with an intrinsic activity over 20 times higher than the single-atom FeN 4 site. Our finding not only opens up a novel strategy to tailor the electronic structure of an atomic site toward boosted activity but also provides new insights into the fundamental understanding of diatomic sites for ORR electrocatalysis.

Meso-/macroporous nitrogen-doped carbon architectures with iron carbide encapsulated in graphitic layers are fabricated by a facile approach. This efficient and robust material exhibits superior catalytic performance toward the oxygen reduction reaction in both acidic and alkaline solutions and is the most promising alternative to a Pt catalyst for use in electrochemical energy devices.