Sonochemical surface modification of a novel Sm2O3@g-C3N4@Bi2O3 ternary hybrid photocatalyst exhibiting efficient solar light harvesting: Degradation of Azure b and photoelectrochemical water splitting

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2024-05, Vol.450, p.115479, Article 115479
• Main Authors: Singh, Kijay Bahadur, Gautam, Neelam, Upadhyay, Deen Dayal, Pandey, Gajanan
• Format: Article
• Language: English
• Subjects: Azure B degradation; Engineered Z-scheme; PEC water splitting reaction; Pseudo-first order kinetics; Ternary composite
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2024.115479

[Display omitted] •Sonochemical surface modification of novel Sm2O3@g-C3N4@Bi2O3 photocatalyst.•Formation of flower like pattern was done.•Sm2O3@g-C3N4@Bi2O3 shown rapid degradation of Azure B in solar radiation.•Effect of dose and pH of the medium also investigated.•Enhanced rate of photoelectrochemical water splitting reaction observed. Engineered Z-scheme photocatalysts have a strong redox activity while also reducing the annihilation of light-induced charge bearers. In this investigation, a solid state twin Z-scheme Sm2O3@g-C3N4@Bi2O3 nanocomposite has been successfully prepared employing bismuth (III) nitrate, samarium chloride and urea as precursor chemicals in a single co-calcination procedure followed by sonochemical surface modification. The formation of flower like multiphasic material is confirmed from SEM and HRTEM images. BET findings suggested the enhancement in specific surface area of Sm2O3@g-C3N4@Bi2O3 and reduced band gap from UV–visible data. Photoluminescence results confirmed the reduction in rate of charge carrier recombination of Sm2O3@g-C3N4@Bi2O3. Presence of samarium is confirmed from XPS analysis. Under direct solar radiation, the surface modified Sm2O3@g-C3N4@Bi2O3 hybrid demonstrated amplified photo-assisted catalytic activity for the degradation of Azure B (AzB) than pristine g-C3N4 and their binary composite Sm2O3@g-C3N4. It is possible to attribute the better solar light absorption, higher separation efficacy of photo-promoted electron-holes to the amplified photo-assisted degradation performance of the Sm2O3@g-C3N4@Bi2O3 composite. The photodegradaton of AzB follows pseudo-first order kinetics and the observed rate constants are 0.0014, 0.0026, and 0.0316 min−1 for g-C3N4, Sm2O3@g-C3N4, and Sm2O3@g-C3N4@Bi2O3 ternary composite. The nanocomposite also demonstrates good stability and recyclability. A unique solid-state twin Z-scheme photocatalytic pathway was also hypothesized in light of the findings. The fabricated ternary hybrid shown efficient photoelectrochemical water splitting reaction for H2 and O2 generation.