Coupling heterointerface engineering with morphological design for high-performance water-splitting electrocatalysts

This study tackles critical challenges in non-noble-metal bifunctional electrocatalysts for the HER and OER, including insufficient intrinsic activity, inefficient mass transport, and limited long-term stability. By synergistically integrating heterointerface engineering with morphological engineering, NiO/NiS₂ heterostructured catalysts featuring a hydrangea-like hierarchical porous architecture are fabricated on textile biomass-derived N-doped carbon. The NiO/NiS₂ heterointerface induces pronounced interfacial electronic redistribution, effectively optimizing the electronic structure of Ni active sites and enhancing intrinsic catalytic activity. Simultaneously, the multidimensional micro-nanochannel architecture endows the catalyst with exceptional superhydrophilic and superaerophobic properties, substantially improving mass-transfer efficiency. Moreover, the heterostructure undergoes controlled dynamic surface reconstruction under operating conditions, forming stable and highly active interfacial phases. As a result, the catalyst delivers excellent overall water-splitting performance, achieving 10 mA·cm^-2at 1.52 V with less than 5 % performance decay after 100 h in alkaline electrolyte, surpassing noble-metal benchmarks (Pt/C || RuO₂). This work establishes general design principles and mechanistic insights for the rational development of efficient and durable non-noble-metal electrocatalysts.