Single-source-precursor synthesis of porous Ni2Si/SiOC composites as oxygen evolution reaction electrocatalyst

In this study, a novel carbon-rich Ni2Si/SiOC ceramic composite was successfully synthesized by polymer-derived ceramic approach, which is found to be catalytically active in the field of oxygen evolution reaction (OER). The synthesis involves the reaction of a commercially available carbon-rich polysiloxane precursor SPR-684 and nickel acetylacetonate, forming a Ni-containing single-source-precursor (SSP). Besides, to investigate the influence of porosity on OER performance, polystyrene (PS) was used as a sacrificial template for pore formation. Thermal treatment of the obtained mixture of SSP and PS at 1400 °C leads to the Ni2Si particles being encapsulated by structural ordered carbon, potentially enhancing the electrical conductivity of the composite. And the sample prepared at 1400 °C presented weight fractions of the crystalline phases Ni2Si and SiC in the amounts of 39.6 wt% and 29.3 wt%, respectively. Regarding the OER performance, with the support of increased conductive carbon formation, the sample obtained at 1400 °C demonstrated the best overpotential of 336 mV versus the reversible hydrogen electrode (RHE) at a current density of 10 mA cm⁻² in 1 M KOH, indicating enhanced performance in the oxygen evolution reaction region.