Photocatalytic solar fuel production and environmental remediation through experimental and DFT based research on CdSe-QDs-coupled P-doped-g-C3N4 composites

• Published in: Applied catalysis. B, Environmental Environmental, 2020-08, Vol.270, p.118867, Article 118867
• Main Authors: Raziq, Fazal, Hayat, Asif, Humayun, Muhammad, Baburao Mane, Sunil Kumar, Faheem, M. Bilal, Ali, Asad, Zhao, Yang, Han, Shaobo, Cai, Chao, Li, Wei, Qi, Dong-Chen, Yi, Jiabao, Yu, Xiaojiang, Breese, Mark B.H., Hassan, Fakhrul, Ali, Farman, Mavlonov, Abdurashid, Dhanabalan, K., Xiang, Xia, Zu, Xiaotao, Li, Sean, Qiao, Liang
• Format: Article
• Language: English
• Subjects: 2,4-Dichlorophenol; Cadmium selenides; Carbon dioxide; Carbon nitride; CdSe quantum dots; Charge efficiency; Chemical energy; Coumarin; Energy; Energy harvesting; Expending visible-light response; Fluorescence; Fluorescence spectroscopy; Fuel production; g-C3N4; Nanocomposites; Phosphorus; Phosphorus doping; Photocatalysis; Photoelectric effect; Photoelectric emission; Photoluminescence; Photons; Quantum dots; Solar energy; Solar energy conversion; Solar fuel; Splitting; Water splitting
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.118867

Photocatalytic overall water and CO2 conversion splitting under visible light irradiation. [Display omitted] •Synthesis of phosphorus doped g-C3N4 (P-CN) with its coupling to CdSe quantum dots (QDs).•For band gap engineering conformation DFT and Time depended-DFT were used.•Expending visible-light response of g-C3N4 upto near infra-red region (700 nm).•Photocatalytic Activities for solar fuel production and environmental remediation. Solar energy harvesting and conversion into useful chemical energy with the aid of semiconductor photocatalysts is a promising technique to solve both energy and environmental issues. This work reports a successful synthesis of CdSe quantum dots (QDs) modified phosphorus doped g-C3N4 (P-CN) for advanced photocatalytic applications. Phosphorus doping and structural coupling with CdSe QDs are shown to significantly extend visible-light response of g-C3N4 up to 700 nm. The optimized sample 4CdSe/P-CN demonstrates enhanced visible-light driven overall water splitting activities for H2 and O2 evolution i.e. 113 and 55.5 μmol.h−1. g−1, respectively, as well as very high photocatalytic CO2 to CH4 conversion efficiency (47 μmol.h−1. g−1). It also exhibit higher activity (78 %) for 2,4-dichlorophenol degradation as compared to pristine CN-sample. Combined photoluminescence, transient/single wavelength photocurrent, photoelectrochemical, and coumarin fluorescence spectroscopy demonstrate that 4CdSe/P-CN nanocomposite exhibit enhanced charge separation efficiency which is responsible for improved visible light catalytic activities. Our work thus provide a new strategy to design low-cost and sustainable photocatalysis with wide visible-light activity for practical overall water splitting and CO2 reduction applications.