Influence of the modification of chlorophyll-rich extracts on the hydrogen evolution reaction of rGO-based electrocatalysts

Abstract

The great efforts to develop alternative electrocatalysts for efficient hydrogen evolution reaction (HER) applications through environmentally friendly synthesis still need to be completed. We explore a green route using spinach extract to simultaneously reduce and functionalize graphene oxide (GO). A spinach extract, rich in green reducing agents and chlorophyll, was obtained and modified by saponification and demetallation to yield Chln-H2 and further used to reduce and functionalize GO in a one-step procedure. The resulting RGO/Chln-H2 electrocatalyst was evaluated on the HER by Lineal Sweep Voltammetry (LSV), achieving a current density of −34.84 mA/cm2 starting its activation from an onset potential of −0.68 V vs reference hydrogen electrode (RHE). The effect of saponification and demetallation produces a new metal-free alternative catalyst with increased current density seven times, boosting hydrogen production performance.