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Updated: May 10, 2025
Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Effect of Trivalent Metal Cations in Layered Double Perovskites on Highly Selective CO2 Photoreduction to CO
Wei Chen1, Yanyi Huang2, Daofu Wu3
1College of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
Abstract:
Trivalent metal cation engineering in vacancy-ordered layered double perovskites (LDP) is a useful strategy to tune photocatalytic activity. However, the regulatory mechanism of cation composition on photocatalytic performance still lacks in-depth understanding. This study explores vacancy-ordered LDP with the formula Cs4CdX2Cl12 (X = Bi, Sb) for photocatalytic CO2 reduction. The catalytic performance is fine-tuned by regulating the composition of M(III)-site metal ions. The yields of CO and CH4 from Cs4CdSb2Cl12 MCs were measured at 23.81 and 2.68 μmol g-1, resulting in a CO selectivity of 89.9%. Cs4CdBi2Cl12 demonstrated higher yields, with CO and CH4 produced at 90.77 and 2.53 μmol g-1, achieving a CO selectivity of 97.2%. In addition, in situ diffuse reflectance infrared Fourier transform spectra reveal that the modulation of metal ions at the M(III)-position can enhance the photocatalytic activity of Cs4CdX2Cl12 (X = Bi, Sb) MCs. Density functional theory (DFT) analysis suggests that Bi displays a lower energy barrier than Sb for the rate-determining step, thus facilitating the effective photocatalytic reduction of CO2 to CO. These findings highlight the influence of metal cation selection on structural properties and catalytic performance.
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