Towards a fully biodegradable oxygen reducing electrocatalyst

Abstract

• A carbon-free fully biodegradable electrocatalyst towards ORR was reported. • 2D-hematene was produced via exfoliation. • ZnO nanostructures were electrochemically deposited onto hematene substrates. • Different morphologies of ZnO were studied and the results presented. • The designed ZnO/hematene catalyst showed current density 2-fold higher than only ZnO. Renewable source of energy and the materials involved in the design of new electronics are critical elements for sustainable development. Great improvement has been done to expand clean sources of energy; however, despite remarkable progress, clean energy combined to biodegradability is still a challenge. Since the first fully biodegradable silicon electronic system using thin‐film magnesium, magnesium oxide, and silicon nanomembranes in 2012, there has been an ongoing push to study a broader range of biodegradable electrocatalytic materials. To date, it is still challenging to produce biodegradable conductive nanomaterials. In this study, the oxygen reduction reaction (ORR) is demonstrated using a carbon-free fully biodegradable electrocatalyst designed with exfoliated 2D-hematene and ZnO nanostructure. This novel fully biodegradable system showed current density of ∼2.2 mA.cm −2 (vs 1 mA.cm −2 for ZnO) and good stability for 14 h. ZnO/Hematene electrocatalyst is a promising step towards biodegradable power source.