Z‐Scheme Strategy in Polymeric Graphitic C3N5/CdS Core–Shell Heterojunction Drives Long‐Lived Carriers Separation for Robust Visible‐Light Hydrogen Production. Issue 5 (3rd December 2022)

• Record Type: Journal Article
• Authors: Wang, Xin; Wu, Kaili; Cao, Wei; Rui, Kun; Wang, Wenchao; Zhu, Ruixue; Zhu, Jixin; Yan, Zhiping
• Is Part Of: Advanced materials interfaces. Volume 10:Issue 5(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-03
• Subjects: core–shell -- g‐C3N5 -- hydrogen -- photocatalysis -- transient absorption spectroscopy; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202201627
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: The intrinsic charge carriers' recombination and excited states decay greatly suppress the active species survival and photo(electro)catalytic performance. Inspired by Z‐scheme strategy, the polymeric nitrogen‐rich carbon nitride/cadmium sulfide (g‐C3 N5 /CdS) core–shell heterojunction is constructed to optimize photocatalytic performance. The optimal hydrogen production rate of g‐C3 N5 /CdS heterojunction catalyst under visible light without adding extra cocatalyst is up to 7860 µmol h −1 g −1, which is 3 and 71 times higher than that of pure CdS and g‐C3 N5 photocatalysts, respectively. The femtosecond transient absorption spectroscopy is employed to observe the kinetic decay of carriers in the heterojunction, revealing the ultrafast charge trapping process (τ1 = 52.3 ps) and long‐lived excited states (τ3 = 1109.2 ps) in g‐C3 N5 /CdS photocatalyst. Meanwhile, density functional theory calculation results comprehensively suggest the promoted charge separation in heterojunction. Cost‐effective Z‐scheme g‐C3 N5 /CdS photocatalyst in this work shows a great potential for sustainable and high‐efficiency solar‐to‐H2 conversion. Abstract : A simple self‐assembly method is used to construct a nitrogen‐rich carbon nitride/cadmium sulfide (g‐C3 N5 /CdS) heterojunction with core–shell structure for H2 production without noble‐metal cocatalysts. The formation, transfer, and recombination processes of photogenerated carriers are investigated using femtosecond time‐resolved absorption spectroscopy. Experimental characterizations and density functional theory calculation are conducted to comprehensively explain the promoted charge separation in this heterojunction.