摘要
Regulating the pore structure of a zirfon-based diaphragm is critical to promoting a high-rate alkaline electrolyzer,but it is still a big challenge to respond“trade-off”between the thickness of the diaphragm and the current density/gas barrier behavior.In this work,a porous hydrophilic skin layer with~μm thick of polyvinyl alcohol(PVA)has been successfully constructed and casted onto the thin zirfon-type separator composite(V-Zirfon-350μm).The V-Zirfon-350μm separator generates a high KOH uptake(>90%),low area resistance(0.2026Ωcm^(2))but a low electrolyte permeation flux density(5.2×10^(-4) mL cm^(-2) s^(-1) at 0.5 bar),which largely surpasses the state-of-the-art commercial Zirfon UTP-500μm diaphragm.When coupled with Raney Ni cathode and NiCoMo-LDH anode catalysts,the V-Zirfon-350μm separator offers a high current density over 1300 mA cm^(-2)@2.0 V(80℃ in 30%KOH)and a superior stability of 300 h under 800 mA cm^(-2) for alkaline water electrolysis(AWE).Specifically,the voltage is merely~3.5 V for two electrolytic cells connected in series,which can be even conducted for more than 1300 h at different operational conditions.This work provides a novel methodology for the practical application of a thin Zirfon-based diaphragm.
基金
supported by the National Key Research and Development Program of China(2022YFE0138900)
the National Natural Science Foundation of China(21972017)
the“Scientific and Technical Innovation Action Plan”Basic Research Field of Shanghai Science and Technology Committee(19JC1410500).
