Synthesis and characterization of Bi-doped g-C3N4 for photoelectrochemical water oxidation

Revaprasadu, Neerish; El-Rouby, Waleed M.A.; Khan, Malik Dilshad; Aboubakr, Ahmed; Farghali, Ahmed A.; Millet, Pierre

Synthesis and characterization of Bi-doped g-C3N4 for photoelectrochemical water oxidation

dc.contributor.author	Revaprasadu, Neerish
dc.contributor.author	El-Rouby, Waleed M.A.
dc.contributor.author	Khan, Malik Dilshad
dc.contributor.author	Aboubakr, Ahmed
dc.contributor.author	Farghali, Ahmed A.
dc.contributor.author	Millet, Pierre
dc.coverage.conference	issn
dc.date.accessioned	2025-11-25T10:34:31Z
dc.date.available	2025-11-25T10:34:31Z
dc.date.issued	2020
dc.departmentName	Chemistry
dc.description.abstract	Photoelectrochemical (PEC) water splitting has emerged as a promising technology for the storage of renewable energy sources, via the production of hydrogen, a clean and multi-purpose chemical energy vector. The key component in a PEC cell is the photoanode where light energy is absorbed and transformed into electron-hole pairs of appropriate energy for water photo-oxidation. We report on the synthesis of g-C3N4 materials, with an elongated nano-structure, fabricated by the direct pyrolysis of supramolecular melamine used as a chemical precursor. The as-prepared material was used to host specific amounts of bismuth, a doping element used to adjust the band gap of the hosting matrix. The presence of Bi in the photoanodes was confirmed by energy dispersive x-ray analysis (EDX) analysis. Powder X-ray (p-XRD) and Fourier transform infrared (FT-IR) measurements performed on the photoanodes confirmed the absence of Bi-based oxides, and showed that bismuth may bonded to nitrogen atoms inside the voids of the g-C3N4 skeleton. Differential reflective spectroscopy (DRS) measurements revealed that the band gap energy was reduced upon introduction of Bi into g-C3N4. From photoluminescence (PL) plots, it was observed that the 2.5% Bi doping induced a 6-fold electron-hole separation, compared to the pristine g-C3N4. PEC water splitting measurements showed that 2.5% Bi doping approximately doubled the activity of g-C3N4 towards water oxidation. Electrochemical impedance spectroscopy (EIS) measurements showed that Bi doping was an effective method for decreasing the charge transfer across the electrode/electrolyte interface; 2.5% Bi-g-C3N4 was reduced by around 2.4 times compared to that of pristine g-C3N4. Bode-phase plots accompanied EIS spectra revealed that the lifetime of the photo-generated electrons in neat g-C3N4 was improved as a result of Bi doping. The band gaps and the positions of the valence and conduction bands were determined from Mott–Schottky plots.
dc.faculty	Faculty of Science, Agriculture and Engineering
dc.format.preprint	No
dc.identifier.citation	El-Rouby, W.M., Aboubakr, A.E.A., Khan, M.D., Farghali, A.A., Millet, P. and Revaprasadu, N., 2020. Synthesis and characterization of Bi-doped g-C3N4 for photoelectrochemical water oxidation. Solar Energy, 211, pp.478-487.
dc.identifier.issn	1471-1257 (online)
dc.identifier.issn	0038-092X (print)
dc.identifier.other	https://doi.org/10.1016/j.solener.2020.09.008
dc.identifier.uri	http://hdl.handle.net/10530/58397
dc.inproceedings	issn
dc.issuenumber	211
dc.keynote	issn
dc.pages	478 - 487
dc.peerreviewed	Yes
dc.publisher	Elsevier
dc.subject	Photoelectrochemical water splitting
dc.subject	Graphitic carbon nitride
dc.subject	Bismuth doped
dc.title	Synthesis and characterization of Bi-doped g-C3N4 for photoelectrochemical water oxidation
dc.title.journal	Solar Energy
dc.type	Journal Article
dspace.entity.type	Publication
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