ZrO2 embedded in NiFe-LDH/PVA network as the membrane of alkaline water electrolysis

We have proposed a cost-effective method to make a membrane for alkaline water electrolysis by combining organic polymers with inorganic materials, to achieve high ionic conductivity, excellent alkaline stability, and superior electrochemical properties. In this study, NiFe layered double hydroxide (LDH) powders synthesized hydrothermally, mixed with 2 wt% ZrO 2 are physically crosslinked with polyvinyl alcohol (PVA) gel to form a ZrO 2 /NiFe-LDH@PVA slurry. The slurry has been coated onto a non-woven fabric to reduce being oxidated by the anodic active substances during the electrolysis process, also, a layer of nylon gauze is sandwiched to improve its mechanical properties. The resulted membrane exhibited exceptional mechanical strength (24.9 MPa tensile strength) and remarkable hydroxide ion conductivity (86.52 mS cm −1 at 90 °C). Furthermore, NiCo/NM and NiFe/NM catalysts were electrodeposited and integrated with the ZrO 2 /LDH@PVA composite membrane to assemble an alkaline water electrolysis device. When tested in 6 M KOH electrolyte at 70 °C and 2.0 V, the device achieved a current density of 781 mA cm −2 and maintained stable operation for at least 400 h.