Praseodymium Oxide Improving the Activity of a Silver-Loaded Calcium Titanate Photocatalyst for Carbon Dioxide Reduction with Water

Abstract

Heterogeneous photocatalytic CO2 reduction with water has attracted great attention. Although the addition of Ag nanoparticles (NPs) as a cocatalyst on a semiconductor photocatalyst has been known to improve both the photocatalytic activity and reaction selectivity for CO2 reduction, the addition of Pr as Pr6O11 species on the surface of an Ag-loaded CaTiO3 (CTO) photocatalyst further improved the photocatalytic activity. The different calcination temperatures for the sample preparation changed the state of Pr species, and it strongly influenced the photocatalytic performance. The Pr6O11 species was found to be loaded between the CTO surface and Ag NPs on the Ag/Pr/CTO photocatalyst, proposing that it improves the electron migration from the CTO photocatalyst to Ag NPs via the Pr6O11 layer.