Efficient photocatalytic H2O2 production by using unstable S-O functional groups as oxygen adsorption and active sites in shuttlecock waste-derived N, S-doped carbon dots

The growing demand for environmentally friendly hydrogen peroxide (H₂O₂) production has fueled extensive research into synthesis strategy for photocatalysis though the use of the sunlight. However, the current challenge lies in the efficient production of photocatalysts without relying on sacrificial agents in the atmospheric environment. In this study, we propose a breakthrough approach to synthesize N, S co-doped carbon dots (N, S-CDs) by utilizing disulfide bonds in discarded shuttlecock waste and demonstrate its impressive performance (2062.4 µM g^-1h⁻¹) for photocatalytic H₂O₂ production. The significance of the S-O functional groups in N, S-CDs is not limited to the structural elements, since it is not only the key adsorption site for oxygen, but also active site to promote electron transfer from the bulk phase to surface of N, S-CDs during the oxygen reduction reaction (ORR) process for photocatalytic H₂O₂ production. Furthermore, femtosecond transient absorption spectroscopy (fs-TA) indicates that the presence of the S-O moiety is effective in prolonging the electron lifetime, which effectively inhibit the recombination of electron-holes, thus greatly improving carriers’ utilization. These findings provide new insight for the design of biomass carbon-based photocatalysts, which have important implications for the industrial application of solar energy for the synthesis of H₂O₂.