Synthesis of Double Defects in g‐C₃N₄ to Enhance the H₂O₂ Production by Dual‐Electron O₂ Reduction

Abstract

In this work, the graphitic carbon nitride with −C≡N defects and S‐defects (N2‐SCN‐4) was constructed. The H2O2 production efficiency of N2‐SCN‐4 was 1423.3 μmol g‐1 h‐1 under the visible light (λ ≥ 420 nm) irradiation, which was 15.4 times that of pristine g‐C3N4. The −C≡N groups promote the adsorption of H+ and the S‐defects provide the active center for the adsorption and activation of O2. Furthermore, the surface morphology, microstructure, and photoelectric chemical properties of samples were investigated by a series of characterizations, and the response range of N2‐SCN‐4 to visible light increases obviously. Meanwhile, the efficiency of photo‐produced charge separation and the selectivity of H2O2 production were discussed in detail. The experimental and characterization results confirmed that the charge separation efficiency and the selectivity of the 2e− O2 reduction reaction (ORR) were improved under the synergistic effect of the double defects. This work provides a strategy for improving the photocatalytic performance of photocatalysts.

Polymer photocatalysts for photocatalytic hydrogen peroxide production

“…Yang et al introduced –CN defects and S-defects into g-C 3 N 4 via a calcination method. 111 The introduction of double defects narrowed the band gap of the photocatalyst and enhanced charge separation. More importantly, the S-defects served as active centers for O 2 adsorption and activation (Fig.…”