LED light-driven mineralization of methylparaben using Pd nanoparticles/BiVO4 Schottky heterojunction catalyst fabricated by an LED light-assisted photoreduction method

• Published in: Journal of environmental chemical engineering 2024-12, Vol.12 (6), p.114882, Article 114882
• Main Authors: Nguyen, Trinh Duy, Doan, Que-Minh T., Hoang, Lan-Anh T., Lee, Taeyoon
• Format: Article
• Language: English
• Subjects: BiVO4; LED; Methylparaben; Pd nanoparticles; Photoreduction method; Schottky heterojunction
• ISSN: 2213-3437
• DOI: 10.1016/j.jece.2024.114882

The degradation of methyl paraben (MPB) through photocatalysis utilizing BiVO4 (BV) has proven to be an effective technique. This research focuses on the synthesis of the Pd/BiVO4 metallic-semiconductor heterojunction through the targeted photodeposition of Pd0 nanoparticles (NPs) on the reduction facets of BiVO4 pine structures by means of two light sources: a 300 W Xenon lamp (Pd/BV-Xenon) and a 40 W light emitting diode (LED) lamp (Pd/BV-LED). Both Pd/BV-Xenon and Pd/BV-LED demonstrate a remarkable MPB elimination rate exceeding 90 % within 180-minute LED ligh exposure, showcasing a more than fourfold increase compared to untreated BV. Besides, Pd/BV-LED exhibits impressive MPB mineralization rates achieving a 62 % Chemical Oxygen Demand (COD) removal, slight higher the 52 % COD removal achieved Pd/BV-Xenon, and far surpassing the modest 4 % COD removal achieved by bare BV. These outcomes indicate that the establishment of the Schottky junction between Pd0 NPs and BiVO4 can restrict the recombination of photoinduced charge carriers, thereby improving MPB mineralization. Notably, using LED lamps with lower power consumption and lower initial investment costs yields comparable efficiency to using high-power Xenon lamps with higher initial investment costs for production of Pd/BiVO4 metallic-semiconductor heterojunction. In addition, the study delved into the practical application aspects encompassing photocatalysis mechanisms, degradation pathways of MPB, toxicity analysis of intermediate products, and the optimization of reaction parameters within the photocatalytic system. In summary, the implementation of the photocatalytic system with Pd/BiVO4 Schottky heterojunction could offer a reliable and versatile method for enhancing oxidation processes in wastewater treatment. [Display omitted] •Pd/BiVO4 heterojunction fabricated by Xenon and LED light-assisted photoreduction method.•Schottky junction formation confirmed, reducing recombination of charge carriers.•Over 90 % MPB removal achieved with Pd/BV-LED and Pd/BV-Xenon under LED exposure.•Pd/BV-LED showed 62 % COD removal, surpassing the performance of untreated BV.•Minimal environmental toxicity from intermediate products in Pd/BV-LED system.