Electrocatalytic activity of nickel and cobalt cinnamate for oxygen evolution reaction with reduced graphene oxide or carbon nanotube

The stability and catalytic properties of coordination polymers (CPs) in electrochemical reactions can be improved by incorporating supporting materials. In this study, the enhancement of the electrocatalytic performance of two isostructural CP electrocatalysts, Ni and Co trans-cinnamate (t-ca), was investigated using three carbon-based supports: reduced graphene oxide (rGO), multi-walled carbon nanotubes (MWCNT), and carboxylic acid-functionalized MWCNT (MWCNT-COOH). The objective was to improve the catalytic performance in the oxygen evolution reaction (OER). Investigation of the OER characteristics of each catalyst/support combination, Ni t-ca/MWCNT-COOH and Co t-ca/rGO combinations, exhibited overpotential reductions of approximately 20 and 35 mV, respectively, compared to the unsupported catalyst. The enhanced electrocatalytic properties can be attributed to chemical interactions such as π–π interactions and hydrogen bonding between the supports and the π-conjugated hydrocarbon and carboxylate groups present in the t-ca ligand.