Aluminum-induced electron structure on nickel phosphide for effective hydrazine‑assisted water splitting at large current density

Hydrazine-assisted water electrolysis emerges as a promising strategy to replace conventional device for effective hydrogen generation. Limited to the great difference of intermediate adsorption energy for hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), the design and fabrication of bifunctional catalysts is still a knotty challenge in industrial conditions. Herein, Al-doped Ni2P nanoflower architecture grown in-situ on nickel foam (Al-Ni2P/NF) is fabricated through the combination of hydrothermal process and subsequent phosphorization treatment. Ascribed to the redistribution of electron state and optimization of reaction intermediate energy induced by Al, Al-Ni2P/NF expresses distinguished bifunctional catalytic performance with ultralow potentials of −205 and 300 mV at 500 mA cm−2 for HER and HzOR, respectively. When integrated into hydrazine-assisted water splitting as both the anode and cathode, only 0.717 V is required to reach a large current density of 500 mA cm−2. Specially, a novel integrated system driven entirely by sustainable solar energy is proposed, generating energy-saving hydrogen and purify hydrazine-containing sewage simultaneously. This work provides an attracting and practical path for accelerating the development of hydrogen economy.