Water splitting is a sustainable and clean hydrogen-production technology, but driven either by solar energy with natural intermittent, or by power grid with high cost, which is not conductive to sustainable development. Additionally, the sluggish anodic oxygen evolution reaction (OER) remains a huge obstacle for efficient hydrogen production. Herein, an intersected nanosheets decorating micro-walls structure nickel-cobalt phosphide grown on Ni foam electrode (NiCoP/NF) is prepared, and displays good hydrogen evolution reaction (HER), excellent hydrazine oxidation reaction (HzOR) and enhanced NiCoP/NF//Zn battery capacity performance. Based on the trifunctional NiCoP/NF electrode, a continuous solar-driven energy-saving hydrogen generation is constructed. The solar cells drive the efficient hydrogen production and hydrazine degradation plus simultaneously charge the NiCoP/NF//Zn battery during the day; then the charged NiCoP/NF//Zn battery provide high output voltage to drive hydrogen generation and hydrazine degradation at night. The continuous solar-driven energy-saving hydrogen generation plus sewage treatment strategy exhibits a new way for clean and sustainable energy supply plus curbing environmental pollution. •The nanosheets decorating micro-walls structure NiCoP was prepared.•The NiCoP exhibited superior HER and excellent HzOR performance.•The NiCoP achieved the unprecedented low potential for hydrogen generation.•Trifunctional NiCoP demonstrated the uninterrupted efficient hydrogen generation.