A novel S-scheme photocatalyst Fe2O3/Bi2O3/g-C3N4 with enhanced visible-light photocatalytic performance for antibiotic degradation and CO2 reduction: RSM-based optimization

Abstract

The degradation of pollutants and reduction of CO2 to hydrocarbon fuels using photocatalysis is a potential approach to reducing CO2 emissions and decreasing environmental contamination. This study introduces an innovative S-scheme photocatalyst (Fe2O3/Bi2O3/g-C3N4) synthesized through simple methods for the first time. The structural, morphological, and optical properties of the synthesized photocatalysts were comprehensively characterized using XRD, XPS, FTIR, SEM, TEM, HR-TEM, BET, UV–vis DRS, PL, ESR, and mott-Schottky analyses, respectively. The visible light photodegradation of tetracycline (TC) antibiotic and CO2 conversion were carried out in order to evaluate the photocatalytic performance of these synthesized materials. Using the RSM-CCD approach, the influence of key variables on TC degradation were optimized. The results indicated that the optimized photocatalyst (45-FeBiC) exhibited higher photocatalytic performance (99.87 %) compared to other samples via photogenerated •O2−, and •OH. Additionally, four cycle studies verified that the 45-FeBiC nanocomposite had adequate photostability. After 6 h of visible light illumination, the 45-FeBiC catalyst generated 33.84 μmol/g of CO and maintained 96.2 % of its initial photocatalytic activity after 30 h of reaction. The enhanced photocatalytic efficiency of the 45-FeBiC nanocomposite is attributed to the photosensitization effect of 3 wt%-Fe2O3/Bi2O3 on g-C3N4 within the S-scheme photocatalytic framework.