Intrinsic Charge Polarization in Bi19S27Cl3 Nanorods Promotes Selective CC Coupling Reaction during Photoreduction of CO2 to Ethanol. Issue 5 (19th December 2022)

• Record Type: Journal Article
• Authors: Das, Kousik; Das, Risov; Riyaz, Mohd; Parui, Arko; Bagchi, Debabrata; Singh, Ashutosh Kumar; Singh, Abhishek Kumar; Vinod, Chathakudath P.; Peter, Sebastian C.
• Is Part Of: Advanced materials. Volume 35:Issue 5(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-19
• Subjects: C C coupling -- charge polarization -- CO 2 reduction -- ethanol -- photocatalysis; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202205994
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Obtaining multi‐carbon products via CO2 photoreduction is a major catalytic challenge involving multielectron‐mediated CC bond formation. Complex design of multicomponent interfaces that are exploited to achieve this chemical transformation, often leads to untraceable deleterious changes in the interfacial chemical environment affecting CO2 conversion efficiency and product selectivity. Alternatively, robust metal centers having asymmetric charge distribution can effectuate CC coupling reaction through the stabilization of intermediates, for desired product selectivity. However, generating inherent charge distribution in a single component catalyst is a difficult material design challenge. Here, a novel photocatalyst, Bi19 S27 Cl3, is presented which selectively converts CO2 to a C2 product, ethanol, in high yield under visible light irradiation. Structural analysis through transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and X‐ray absorption spectroscopy reveals the presence of charge polarized bismuth centers in Bi19 S27 Cl3 . The intrinsic electric field induced by charge polarized bismuth centers renders better separation efficiency of photogenerated electron–hole pair. Furthermore, charge polarized centers yield better adsorption of CO* intermediate and accelerate the rate determining CC coupling step through the formation of OCCOH intermediate. Formation of these intermediates is experimentally mapped by in situ Fourier‐transform infrared spectroscopy and further confirmed by theoretical calculation. Abstract : The concept of intrinsic charge polarization has been efficiently exploited for the CC coupling reaction. The selected catalyst, Bi19 S27 Cl3 has three suitably arranged Bi centers with asymmetric charge distribution. The charge polarized Bi centers facilitate the formation of COCOH* intermediate which has been realized as the crucial step for synthesizing ethanol from CO2 .