Cobalt disulfide/graphite foam composite films as self-standing electrocatalytic electrodes for overall water splitting

Abstract

The development of ecofriendly electrocatalysts with earth-abundant metal elements for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is important for overall water splitting to generate clean and sustainable chemical energy. Here, we report a self-standing cobalt disulfide/graphite foam (CoS₂/GF) electrocatalytic electrode for this purpose. It showed high catalytic activities for both the HER and OER, requiring only a cell voltage of 1.74 V to achieve a current density of 20 mA cm⁻² for overall water splitting in an alkaline electrolyte. This three-dimensional microporous electrocatalytic electrode is cheap and available in a large area; thus, it is attractive for practical applications.