Taking Advantage of Potential Coincidence Region: Advanced Self-Activated/Propelled Hydrazine-Assisted Alkaline Seawater Electrolysis and Zn–Hydrazine Battery

论文作者：Hao-Yu Wang，Lei Wang，Jin-Tao Ren，Wenwen Tian，Minglei Sun，Yi Feng，Zhong-Yong Yuan*

发表期刊：ACS Nano2023, 17, 11, 10965–10975

Hydrazine-assisted water electrolysis presents a promising energy  conversion technology for highly efficient hydrogen production. Owing to  the potential coincidence region between hydrogen evolution reaction  (HER) and hydrazine electro-oxidation, hydrazine oxidation reaction  (HzOR) exhibits specific advantages on strategy combination, device  construction, and application expansion. Herein, we report a  bifunctional electrocatalyst of porous Ni foam-supported interfacial  heterogeneous Ni₂P/Co₂P microspheres (denoted  NiCoP/NF), which takes full advantage of this potential coincidence  region. Thanks to the 3D microsphere structure and strong interfacial  coupling effects between Ni₂P and Co₂P, NiCoP/NF  demonstrates excellent bifunctional electrocatalytic performance,  requiring ultralow overpotentials of 70 and 230 mV at 10 mA cm^–2  for HER and HzOR, respectively. When using NiCoP/NF as both electrodes,  HzOR-assisted water electrolysis exhibits considerably decreased  potentials compared with the electro-oxidation of other chemical  substrates. Furthermore, the potential coincidence region of 0.1 V makes  the application of self-activated/propelled hydrazine-assisted alkaline  seawater electrolysis, hydrazine-containing wastewater treatment, and  Zn–hydrazine (Zn-Hz) battery realistic. The concept of potential  coincidence region provided in this work has significant implications  for water electrolysis and other related applications.