Construction of spindle structured CeO2 modified with rod-like attapulgite as a high-performance photocatalyst for CO2 reduction

Abstract

In this study, a spindle structured CeO₂ photocatalyst modified with rod-like attapulgite (CeO₂/ATP) was successfully prepared by simple high temperature calcination. ATP was deposited in the precursor solution of CeO₂ and then heating up the mixture afforded the CeO₂/ATP photocatalyst. The photocatalyst showed remarkable reduction efficiency for CO₂. CO (309.44 μmol g⁻¹ h⁻¹) and CH₄ (184.33 μmol g⁻¹ h⁻¹) are the major products for CO₂ reduction obtained by using the optimum proportion of the CeO₂/ATP photocatalyst; the yield of CO and CH₄ was about 3 and 3.6 times higher than that of CeO₂, respectively. The improvement in the CO₂ reduction efficiency originated from the higher conductivity of ATP, which promoted electron transport and enhanced the separation efficiency of the electron holes. At the same time, the introduction of ATP inhibited the accumulation of CeO₂ and also increased the active sites for CO₂ reduction. Moreover, a possible photocatalytic mechanism for the CO₂ reduction reaction was proposed based on the experimental results. In addition, this study provides new insights for the simple preparation of other photocatalysts with high performance for CO₂ reduction.