Enhanced thermal assisted photocatalysis reduction of carbon dioxide over a Fe2-xGaxO3 solid solution

alpha-Fe2O3 is considered as a promising photocatalytic material due to its low cost, easy availability, and excellent visible light absorption. However, its photocatalytic efficiency is still limited by fast charge recombination. Herein, we report the introduction of Ga in the form of Fe2-xGaxO3 solid solution and the corresponding effect on the electronic structure and photoelectrical activity. The introduction of Ga, suggested by the results of theoretical calculation, reverses the electron spin state in the conduction band, which is beneficial to the suppression of carrier recombination. The above conclusion is further supported by the experimental results. Among the range of materials synthesized, Fe1.96Ga0.04O3 displays the best photothermal activity towards CO2 reduction, in which the CO evolution rate is about 2.4 times that of pure Fe2O3. This work provides an alternative way to improve the activity of alpha-Fe2O3.

Automated summary

Alpha-Fe2O3 is a promising photocatalytic material with low cost and excellent visible light absorption, but its efficiency is limited by charge recombination. This study introduces Ga in the form of Fe2-xGaxO3 solid solution to improve the electronic structure and photoelectrical activity. The introduction of Ga reverses the electron spin state, suppressing carrier recombination. Experimental results support the theoretical calculations, and Fe1.96Ga0.04O3 shows the best photothermal activity for CO2 reduction, with a CO evolution rate 2.4 times higher than pure Fe2O3. This work provides an alternative approach to enhance the activity of alpha-Fe2O3.