Ni/Fe based electrocatalyst for highly-efficient anion exchange membrane water electrolysis.

Anion exchange membrane water electrolysis (AEMWE) is a feasible pathway to industrial-scale production of hydrogen due to the use of low cost, non-precious metal catalysts. In this study, we demonstrate a stable NiFe 2 O 4 anodic oxygen evolution reaction (OER) catalyst to achieve durable and efficient AEMWE via a simple strategy combining hydrothermal and thermal reduction reactions. The prepared NiFe 2 O 4 -50 catalyst, with polyhedral-sphere hybrid morphology and abundant oxygen vacancies, exhibits an overpotential of 280 mV at 50 mA cm−2 and a Tafel slope of only 44.6 mV dec−1 for OER. Moreover, its use as oxygen evolution electrode in AEMWE cell assembled with a Pt/C cathode show excellent water electrolysis performance with a current density of high to 4 A cm−2 at 1.89 V, a cell voltage of only 1.64 V at 1 A cm−2, as well as good long-term stability over >1000 h of continuous water electrolysis under a current density of 1 A cm−2. The newly developed NiFe 2 O 4 catalyst demonstrates excellent AEMWE performance and has a potential application for practical large-scale hydrogen production. [Display omitted] • Preparation of highly-efficient and durable NiFe 2 O 4 - X for AEMWE. • Hybrid structure and oxygen vacancy are critical for AEMWE activity. • A high current density of 4 A cm−2 is obtained at 1.89 V. • Durability over 1000 h for continuous water electrolysis at 1 A cm−2. • The NiFe 2 O 4 - X catalyst have potential for industrial AEMWE. [ABSTRACT FROM AUTHOR]