Bio-capped and green synthesis of ZnO/g-C3N4 nanocomposites and its improved antibiotic and photocatalytic activities: An exceptional approach towards environmental remediation

• Published in: Chinese journal of chemical engineering 2023-04, Vol.56 (4), p.215-224
• Main Authors: Khan, Iltaf, Wang, Chunjuan, Khan, Shoaib, Chen, Jinyin, Khan, Aftab, Shah, Sayyar Ali, Yuan, Aihua, Khan, Sohail, Butt, Mehwish K., Asghar, Humaira
• Format: Article
• Language: English
• Subjects: Bio-caped green g-C3N4; Degradation pathways; Environmental remediation; Lemon juice mediators; ZnO/g-C3N4 nanocomposite
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/j.cjche.2022.07.031

Schematic representation showing the energy bandgaps and exceptional activities of lemon juice mediated green ZnO/g-C3N4 nanocomposites. [Display omitted] In this research study, we have synthesized the bio-capped ZnO/g-C3N4 nanocomposites by employing lemon juice (Citrus limon) as a stabilizer and mediator. Fruitfully, lemon juice which contains various acidic functional groups and citric acid has the capability to block the surface of g-C3N4 from chemical reactivity and activated the surface of g-C3N4 for various reactions. Consequently, the agglomeration behavior and controlled shape of g-C3N4 has also been achieved. Our experimental results i.e. XRD, TEM, HRTEM, PL, FS, XPS, and PEC have confirmed that the lemon juice mediated and green g-C3N4 (L-CN) have good performances and remarkable visible light photocatalytic activities as compared to the chemically synthesized g-C3N4 (CN). Furthermore, the small surface area and low charge separation of g-C3N4 is upgraded by coupling with ZnO nanoparticles. It is proved that the coupling of ZnO worked as a facilitator and photoelectron modulator to enhance the charge separation of g-C3N4. Compared to pristine lemon-mediated green g-C3N4 (L-CN), the most active sample 5ZnO/L-CN showed ∼ 5-fold improvement in activities for ciprofloxacin (CIP) and methylene blue (MB) degradation. More specifically, the mineralization process and degradation pathways, and the mineralization process of ciprofloxacin (CIP) and methylene blue (MB) are suggested. Finally, our present novel research work will provide new access to synthesize the eco-friendly and bio-caped green g-C3N4 nanomaterials and their employment for pollutants degradation and environmental purification.