Photo-induced Intercalation of Cobalt(II) Tellurium Oxide as an Oxygen Evolution (Photo)electrocatalyst

Abstract

Herein, we report on (a) the application of cobalt(II) telluriumoxide (Co3TeO6) as a photo-electrocatalyst, to enhance thephoto-electrocatalytic (PEC) oxygen evolution reaction (OER) inalkaline media, compared to the electrocatalytic (EC) OER (inthe absence of light), and (b) to store charge upon illuminationand release charge upon the termination of illumination underOER potential bias conditions. These nanomaterials weresynthesized employing the sol-gel method and calcined attemperatures ranging from 400 to 1100 °C. They were physicallycharacterized and tested for their capacity to (i) act as a catalysttowards the OER, under EC and PEC conditions, and (ii) toconvert and store light-energy as chemical-energy. Under PECconditions CTO-900, which predominantly consisted of Co3TeO6,exhibited a five-fold increase in activity compared to ECconditions as current density increased from 0.58 mA cm