Activity and Stability of ZnFe<sub>2</sub>O<sub>4</sub> Photoanodes under Photoelectrochemical Conditions
Ningyan Cheng, Leonie Kanzler, Yiqun Jiang, Andrea M. Mingers, Morten Weiß, Christina Scheu, Roland Marschall, Siyuan Zhang
Abstract
High Resolution Image Download MS PowerPoint Slide Photoelectrochemical (PEC) water splitting is a promising energy conversion and storage technology. The development requires highly active and stable photoanodes to perform the oxygen evolution reaction (OER). Here, we investigated the activity and stability of both pristine and hydrogen-treated ZnFe 2 O 4 . Using an illuminated scanning flow cell setup, we monitored the activity and dissolution rates of ZnFe 2 O 4 under operando PEC conditions. It was found that under PEC water oxidation conditions, ZnFe 2 O 4 does not degrade in basic pH. Moreover, thermally reduced ZnFe 2 O 4 shows expected higher OER activity without compromising the stability compared to the pristine one. Dissolution of ZnFe 2 O 4 was only observed once the applied potential was more cathodic than −0.1 V vs reversible hydrogen electrode as the surface Fe 3+ is reduced regardless of illumination.