Varghese Davis, S R Niranjana, P Joselene Suzan Jennifer, S Muthupandi, J Madhavan, M Victor Antony Raj
Department of Physics, Loyola College, Affiliated to the University of Madras, Chennai, 600034, India.
Loyola Institute of Frontier Energy, Loyola College, Chennai, 600034, India.
Sci Rep. 2025 Jan 2;15(1):320. doi: 10.1038/s41598-024-82926-2.
This study involves a novel CuO/CoFe₂O₄/MWCNTs (CCT) nanocomposite, developed by integrating cobalt ferrite (CoFe₂O₄) and copper oxide (CuO) nanoparticles onto multi-walled carbon nanotubes (MWCNTs), for the degradation of tetracycline (TC) under visible light. The photocatalyst was extensively characterized using XRD, HR-SEM, EDX, HR-TEM, UV-Vis, BET, and PL analysis. The synthesized CoFe₂O₄ and CuO nanoparticles exhibited crystallite sizes of 46.8 nm and 37.5 nm, respectively, while the CCT nanocomposite had a crystallite size of 53 nm. Microscopy confirmed a particle size of 49.2 nm for the nanocomposite, with MWCNTs measuring 15.65 nm in diameter. The band gap energy of the CCT nanocomposite was 1.6 eV, which contributed to its enhanced photocatalytic activity, as evidenced by the lower emission intensity in PL analysis. BET analysis revealed a pore volume of 0.37 cc/g and a surface area of 82.3 m²/g. Photocatalytic performance was tested across various conditions, with adjustments to nanocomposite dosages (0.1-0.5 g/L), TC concentrations (5-25 mg/L), and pH levels (2-10). Under optimized conditions (0.3 g/L CCT, 5 mg/L TC, pH 10, 120 min of visible light exposure), the CCT achieved 98.1% degradation of TC. The optimized parameters were subsequently used to assess TC degradation with individual photocatalysts: CoFe₂O₄, CuO, CT, and CCT. The enhanced photocatalytic efficiency observed can be largely attributed to the improved charge transfer dynamics and effective electron-hole separation facilitated by MWCNT doping. The reaction followed a pseudo-first-order kinetic model, with hydroxyl radicals (OH) identified as the key species in the degradation process. Moreover, the catalyst exhibited 96% retention of its photocatalytic efficiency after five consecutive cycles, demonstrating exceptional stability and reusability. These results emphasize the CCT composite's potential as a highly efficient and sustainable photocatalyst for the remediation of pharmaceutical pollutants in aquatic systems.
本研究涉及一种新型的CuO/CoFe₂O₄/MWCNTs（CCT）纳米复合材料，该材料通过将铁酸钴（CoFe₂O₄）和氧化铜（CuO）纳米颗粒整合到多壁碳纳米管（MWCNTs）上而制备，用于在可见光下降解四环素（TC）。使用XRD、HR-SEM、EDX、HR-TEM、UV-Vis、BET和PL分析对光催化剂进行了广泛表征。合成的CoFe₂O₄和CuO纳米颗粒的微晶尺寸分别为46.8 nm和37.5 nm，而CCT纳米复合材料的微晶尺寸为53 nm。显微镜检查证实纳米复合材料的粒径为49.2 nm，MWCNTs的直径为15.65 nm。CCT纳米复合材料的带隙能量为1.6 eV，这有助于提高其光催化活性，PL分析中较低的发射强度证明了这一点。BET分析显示孔体积为0.37 cc/g，表面积为82.3 m²/g。在各种条件下测试了光催化性能，调整了纳米复合材料剂量（0.1 - 0.5 g/L）、TC浓度（5 - 25 mg/L）和pH值（2 - 10）。在优化条件下（0.3 g/L CCT、5 mg/L TC、pH 10、可见光照射120分钟），CCT实现了98.1%的TC降解。随后使用优化参数评估了单独的光催化剂CoFe₂O₄、CuO、CT和CCT对TC的降解情况。观察到的光催化效率提高很大程度上归因于MWCNT掺杂促进了电荷转移动力学的改善和有效的电子 - 空穴分离。该反应遵循准一级动力学模型，羟基自由基（OH）被确定为降解过程中的关键物种。此外，催化剂在连续五个循环后仍保留其96%的光催化效率，显示出优异的稳定性和可重复使用性。这些结果强调了CCT复合材料作为一种高效且可持续的光催化剂在修复水生系统中药物污染物方面的潜力。
