Augmented electronic metal-support interaction of single-atomic NiNC supported PtRu nanoalloys and their boosted activity and durability for hydrogen evolution and oxygen reduction reactions in both alkaline and acidic media

PtRu nanoalloys anchored on conductive carbon supports have attracted attention for their promising hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) electrocatalytic activity, holding significant promising applications in hydrogen fuel cells, it is still challenging to develop highly efficient and durable catalysts for catalyzing HER/ORR in both alkaline and acidic media. However, it is still challenging to develop highly active and durable catalysts toward HER and ORR in both alkaline and acidic media. In this work, PtRu nanoalloys are uniformly anchored onto the surface of Ni single atoms embedded porous nitrogen carbon (NiNC) via a simple annealing approach. PtRu-NiNC exhibits a remarkable HER activity with overpotentials of only 1.5 mV and 26 mV at 10 mA cm⁻² in acidic and alkaline media, respectively, outperforming PtRu-NC. Meanwhile, PtRu-NiNC also shows excellent ORR performance with more positive half-wave potentials (E_1/2) (0.865 V in acidic media and 0.810 V in alkaline media) compared with these of PtRu-NC. Additionally, PtRu-NiNC exhibits a long-time stability for HER/ORR in both acidic and alkaline media. With HER in acid condition as a prototype reaction, detailed spectroscopic characterization and density functional theory (DFT) calculation demonstrate that Ni single atoms augmented EMSI between PtRu nanoalloys and support, which promotes the electronic reconstruction of PtRu nanoalloys and regulates the d-band center of Pt and Ru away from Fermi level, thus optimizing the moderate adsorption/desorption of H* to increase HER activity. Moreover, the enhanced EMSI in PtRu-NiNC can effectively prevent the migration and agglomeration of PtRu nanoalloys in acidic environment, thus stabilizing PtRu nanoalloys within PtRu-NiNC. The recognition that single-atomic Ni incorporated into NC support induces enhanced EMSI, thus endowing PtRu-NiNC with outstanding activity and durability for bifunctional HER/ORR electrocatlysis, provides a practical strategy for developing hydrogen fuel cells.