Low‐Coordination Single Au Atoms on Ultrathin ZnIn₂S₄Nanosheets for Selective Photocatalytic CO₂Reduction towards CH₄

Abstract

Selective CO 2 photoreduction to hydrocarbon fuels such as CH 4 is promising and sustainable for carbonneutral future. However, lack of proper binding strengths with reaction intermediates makes it still a challenge for photocatalytic CO 2 methanation with both high activity and selectivity. Here, low-coordination single Au atoms (Au 1 -S 2 ) on ultrathin ZnIn 2 S 4 nanosheets was synthesized by a complex-exchange route, enabling exceptional photocatalytic CO 2 reduction performance. Under visible light irradiation, Au 1 /ZnIn 2 S 4 catalyst exhibits a CH 4 yield of 275 μmol g À 1 h À 1 with a selectivity as high as 77 %. As revealed by detailed characterizations and density functional theory calculations, Au 1 / ZnIn 2 S 4 with Au 1 -S 2 structure not only display fast carrier transfer to underpin its superior activity, but also greatly reduce the energy barrier for protonation of *CO and stabilize the *CH 3 intermediate, thereby leading to the selective CH 4 generation from CO 2 photoreduction.

Density‐Functional Theory Studies on Photocatalysis and Photoelectrocatalysis: Challenges and Opportunities

“…CO 2 stands as a principal greenhouse gas, significantly contributing to climate change and global warming. The CO 2 reduction reaction is a pivotal process that transforms CO 2 into valuable products, including CO, [43][44][45][46][47] CH 4 , [43,[48][49][50][51] and a variety of hydrocarbons. [50,[52][53][54][55][56][57][58][59] This transformation is a subject of extensive research in both PC and PEC systems.…”

High-performance artificial leaf: from electrocatalyst design to solar-to-chemical conversion

“…29,30 In order to mitigate the increasing greenhouse effect and achieve the global zerocarbon goal, the development of efficient ways to reduce CO 2 to high value-added chemicals is important for both scientific research and practical applications. [31][32][33][34][35] As multiple proton-coupled electron transfer (PCET) processes are involved in the CO 2 RR, a wide range of products can be generated, 36 including carbon monoxide (CO), formic acid (HCOOH), methanol (CH 3 OH), ethylene (C 2 H 4 ), ethanol (CH 3 CH 2 OH), n-propanol (CH 3 CH 2 CH 2 OH) and many others (Fig. 3).…”

Comprehensive Insight into Construction of Active Sites toward Steering Photocatalytic CO2 Conversion

“…Furthermore, single Au atoms are prone to formation of stronger bonds with *CO intermediates, greatly reduced the energy barrier for protonation of *CO, and stabilized the *CH 3 intermediate, which allowed selective CH 4 generation from CO 2 photoreduction. [24] Notably, the generation of CH 3 OH competes with CH 4 , as their formation pathways contain common intermediates. Specifically, *CO can be converted to CH 3 OH, without a dehydration process, by constantly adding electrons and hydrogenation (*CO + H + + e − → *CHO + H + + e − → *CH 2 O + H + + e − → *CH 3 O+ H + + e − → *CH 3 OH).…”