Synergistic effects on d-band center via coordination sites of M-N3P1 (M = Co and Ni) in dual single atoms that enhances photocatalytic dechlorination from tetrachlorobispheonl A

Yufei Zhou; Weihua Qin; Xiaoli Sun; Yunqing Zhu; Junfeng Niu

doi:10.1016/j.jhazmat.2022.128419

Synergistic effects on d-band center via coordination sites of M-N₃P₁ (M = Co and Ni) in dual single atoms that enhances photocatalytic dechlorination from tetrachlorobispheonl A

J Hazard Mater. 2022 May 15:430:128419. doi: 10.1016/j.jhazmat.2022.128419. Epub 2022 Feb 4.

Authors

Yufei Zhou¹, Weihua Qin¹, Xiaoli Sun², Yunqing Zhu³, Junfeng Niu⁴

Affiliations

¹ School of Water Resources and Hydropower Engineering, North China Electric Power University, Beijing 102206, China.
² Institue of Theoretical Chemistry, Jilin University, Changchun 130023, China.
³ School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
⁴ School of Water Resources and Hydropower Engineering, North China Electric Power University, Beijing 102206, China. Electronic address: niujf@ncepu.edu.cn.

PMID: 35149510
DOI: 10.1016/j.jhazmat.2022.128419

Abstract

Transition metal single atoms (TM-SAs) coordinated with highly electronegative N atoms often suffer from low activity and poor stability, which limiting their application in catalysis. To solve it, a PH₃-assisted annealing strategy is designed to synthesize atomically dispersed TM-SAs (CCoNiP), which is stemmed from a pyrolysis approach of pre-designed CoNi layered double hydroxide (LHD) as a soft-template, and further coordinated with P atoms for adjusting the coordination environment. Characterization results show that the atomically dispersed Co and Ni atoms anchor on the carbon nitride substrate with Co/Ni-N₃P₁ coordination sites. Combined with density functional theory calculations, it is confirmed that multiple coordination sites of Co/Ni-N and Co/Ni-P can modulate d-band center position which increases the catalytic activity of TM-SAs. The formed multiple midgap levels can extend optical absorption ranges. Meanwhile, P-introduction can change the coordination environment, suppress the conversion trend of SAs to high valence state and improve electron separation. All the above characteristics can improve effective degradation from Tetrachlorobisphenol A (TCBPA) under visible light irradiation, achieving 100% removal and 44.1% dechlorination rate.

Keywords: Bimetal single atoms; N,P-coordination; Photocatalytic activity; d-band center.