Ahmed Shoaib, Tan Yie Hua, Mubarak Nabisab Mujawar, Khalid Mohammad, Channa Najeebullah, Karri Rama Rao, Ruslan Khairunnisa Nabilah
Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University, 98009, Miri Sarawak, Malaysia; Department of Chemical Engineering, Dawood University of Engineering and Technology, Karachi, 74800, Pakistan.
Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University, 98009, Miri Sarawak, Malaysia; Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Brunei, Jalan Tungku Link Gadong, BE1410, Brunei Darussalam; Department of Chemical and Petroleum Engineering, Faculty of Engineering, Technology and Built Environment, UCSI University, Cheras, 56000, Kuala Lumpur, Malaysia.
Environ Res. 2025 Mar 1;268:120765. doi: 10.1016/j.envres.2025.120765. Epub 2025 Jan 4.
Bismuth-based photocatalysts proved to have remarkable photoactivity for antibiotic degradation from water. However, the two significant challenges of bismuth-based photocatalysts are the fast charge recombination rate and higher energy band gap. This study successfully synthesised a novel I-Bi/BiWO/MWCNTs (C-WBI) heterostructure composite photocatalysts with shorter energy band-gap and higher charge production capability through interfacial amidation linkage. The photochemical characterization of C-WBI confirms that the interfacial linkage between MWNCTs and I-Bi/BiWO (WBI) significantly boosted the charge production capacity and broadened visible-light harvesting (508 nm), resulting in improved photocatalytic activity. As anticipated, optimized 7%C-WBI shows remarkable adsorption and photocatalytic activity for TC removal compared to pristine WBI (2.27 times) under visible light. TC removal was enhanced to 96.75% from 71.58% (WBI) at mild operating conditions of pH 8, photocatalyst loading of 20 mg, and an initial TC concentration of 20 mg/l. Adsorption equilibrium was best fitted to Langmuir isotherm and pseudo-first-order kinetics with R of 0.998 and 0.997, respectively. In contrast, the photodegradation of TC is best described by pseudo-first-order kinetics with a correlation coefficient of 0.99 and a reaction rate of k of 0.0205 min The effect of co-existing ions (Cl, SO₄⁻ and HCO₃⁻) reveals that the presence of Cl notably inhibited the photocatalytic reaction rate, reducing it to 0.0161min⁻. Quenching experiments identified •O₂⁻ and h⁺ radicals as key contributors to TC degradation, accounting for 63.02% and 60.8%, respectively. Furthermore, 7%C-WBI demonstrated outstanding reusability (82.05%) over 5 consecutive cycles with no obvious changes, thereby confirming the stability of the synthesised composite photocatalysts.
铋基光催化剂被证明对水中抗生素的降解具有显著的光活性。然而，铋基光催化剂面临的两个重大挑战是快速的电荷复合率和较高的能带隙。本研究通过界面酰胺化键合成功合成了一种新型的I-Bi/BiWO/MWCNTs（C-WBI）异质结构复合光催化剂，其具有更短的能带隙和更高的电荷产生能力。C-WBI的光化学表征证实，MWNCTs与I-Bi/BiWO（WBI）之间的界面键合显著提高了电荷产生能力，并拓宽了可见光捕获范围（508nm），从而提高了光催化活性。正如预期的那样，优化后的7%C-WBI在可见光下对TC去除表现出显著的吸附和光催化活性，相比原始WBI提高了2.27倍。在pH为8、光催化剂负载量为20mg、初始TC浓度为20mg/L的温和操作条件下，TC去除率从71.58%（WBI）提高到了96.75%。吸附平衡最符合Langmuir等温线和准一级动力学，相关系数R分别为0.998和0.997。相比之下，TC的光降解最好用准一级动力学描述，相关系数为0.99，反应速率k为0.0205min⁻。共存离子（Cl⁻、SO₄²⁻和HCO₃⁻）的影响表明，Cl⁻的存在显著抑制了光催化反应速率，将其降低到0.0161min⁻。猝灭实验确定•O₂⁻和h⁺自由基是TC降解的关键贡献者，分别占63.02%和60.8%。此外，7%C-WBI在连续5个循环中表现出出色的可重复使用性（82.05%），且无明显变化，从而证实了合成的复合光催化剂的稳定性。
