In situ co-formation of NiO nanoclusters and nickel‑nitrogen-doped carbon enables hierarchical electronic modulation of Pt for efficient methanol oxidation at low Pt loading

The single-atom nickel‑nitrogen-doped carbon (Ni-N-C) structure shows promise as a Pt-based catalyst support for the anode of direct methanol fuel cells (DMFCs), owing to its excellent electronic regulation capability and structural stability. However, the single nickel‑nitrogen (Ni-N_X) coordination environment exhibits limited capacity to modulate the electronic properties of Pt. To further enhance electronic structure modulation, we propose an innovative in situ strategy that simultaneously forms Ni-N_X coordination sites and ultrasmall NiO nanoclusters under a limited oxygen atmosphere, yielding an integrated NiO@Ni-N-C composite support. Subsequently, a 10 % Pt/NiO@Ni-N-C catalyst with a low Pt loading was prepared by microwave-assisted glycol reduction. Electrochemical measurements demonstrated that the in-situ introduction of NiO nanoclusters significantly enhanced both the catalytic activity and stability toward methanol oxidation. The mass activity (MA) of the catalyst was 1.7 times that of the unmodified catalyst. The in-situ incorporation of NiO enhances the catalyst's electrocatalytic performance, and it offers a new paradigm for oxide-guided hierarchical electronic modulation strategies in Pt-based systems.