In situ synthesized S-type heterojunction Bi2O2CO3/CuBi2O4 enable efficient NIR light-driven H2O2 activation for water purification

Hydrogen peroxide (H2O2) was the most commonly used oxidant in advanced oxidation processes to degrade emerging organic pollutants. However, photoactivation of H2O2 by catalysts had the problems of narrow pH application range and low solar energy utilization rate. Herein, the Bi2O2CO3/CuBi2O4 heterojunction photocatalyst was in-situ synthesized, which could activate H2O2 under NIR radiation to degrade organic pollutants and complex heavy metal pollutants. Both in-situ irradiation XPS spectra and DFT supported the S-type charge transfer mechanism. Driven by the IEF and bending band, photogenerated electrons were transferred from Bi2O2CO3 to CuBi2O4, which inhibited the recombination of carriers and promoted the activation of H2O2. The activation rate constant of CBO-2/Vis/H2O2 system for H2O2 was 0.0403 min-1, which was 36.6 times that of the original BOC. This work provided new systematic insights into H2O2 activation by S-scheme heterojunction and had implications for wastewater treatment.