Electrochemical behavior of heteroatom doped on reduced graphene oxide with RuO2 for HER, OER, and supercapacitor applications

The electrochemical evolution of H2 using a metal electrocatalyst at a low overpotential is a major area of research aimed at sustainable energy. The high cost of Pt-based catalysts is a significant limitation to large-scale H2 generation. Strategies for the preparation of low-cost and stable electrocatalysts are essential for future H2 generation. In this study, we prepared RuO2 particles decorated on phosphate-doped reduced graphene oxide (rGO) layer for superior electrocatalytic hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and supercapacitor performance. Composite materials are characterized using various techniques such as XRD for crystalline nature, FE-SEM and EDX, HR-TEM for morphology, elemental composition, lattice structure, XPS for elemental composition and oxidation states and BET for specific surface area. The RuO2-P-rGO electrocatalyst had a low overpotential and the lowest Tafel slope, suggesting that the HER (43 mV) and OER (194 mV) performance was excellent. The structural properties of RuO2-P-rGO contributed to its enhanced stability in long-term HER and OER analyses. The electrochemical efficiency of the RuO2-P-rGO composite was analyzed in a 0.5 M H2SO4 electrolyte. Enhanced electrochemical supercapacitor performance was achieved for the RuO2-P-rGO material, with a maximum specific capacitance of 606 F g−1. RuO2-P-rGO achieved maximum capacitance higher than that of the bare electrodes, which indicates the relatively high active surface area of the RuO2-P-rGO electrocatalyst.