In situ α-Fe2O3 modified La2Ti2O7 with enhanced photocatalytic CO2 reduction activity†
Abstract
Developing high-efficiency photocatalysts for CO2 photoreduction is one of the potential solutions to address both energy and pollution issues. In this study, α-Fe2O3 modified La2Ti2O7 was successfully synthesized with intimate contact between La2Ti2O7 and α-Fe2O3, greatly facilitating the carrier separation and transfer during the photocatalytic reaction. The activity and stability for photocatalytic CO2 reduction over α-Fe2O3/La2Ti2O7 were significantly improved as compared with the La2Ti2O7 substrate. The optimized 3% α-Fe2O3/ La2Ti2O7 composite showed excellent CO2 reduction activity after 5 h consecutive illumination, and the total utilized photoelectron number (UPN) reached 7.76 μmol, which was about 4.4 times higher than that of the pristine La2Ti2O7. The steady-state photoluminescence spectra, time-resolved photoluminescence spectra (TRPL) and photocurrent response results showed that the improved charge separation efficiency was the key factor to enhance the photocatalytic activity. This work provides novel insights into the design and fabrication of photocatalysts of high performance for CO2 reduction for solar-to-energy applications.