Asghari Gita, Mahdikhah Vahid, Kalantarian Kooshan, Sheibani Saeed
School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran.
Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, NC, 27695, United States.
Environ Res. 2025 Jul 1;276:121502. doi: 10.1016/j.envres.2025.121502. Epub 2025 Mar 29.
In this paper, a SrTiO/CuO/CNT nanocomposite was synthesized through a co-precipitation to achieve better visible light photocatalytic performance. Analysis of X-ray diffraction (XRD) combined with field emission scanning electron microscopy (FESEM), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed a successful integration of CuO and CNTs into the SrTiO nanoparticle. The modifications resulted in a smaller particle size while narrowing the bandgap to 2.85 eV. They enhanced electric charge capabilities with lower PL intensity, increased photocurrent density, and decreased charge transfer resistance. The photocatalytic performance was evaluated for both organic pollutant degradation and hydrogen production through water splitting. The nanocomposite demonstrated complete degradation of methylene blue (MB) within 60 min, with high efficiency for other pollutants like methyl orange (MO) and rhodamine B (RhB). A study of the mechanism using scavenger methods identified the type-II charge transfer while showing superoxide radicals act as main reactive species. The nanocomposite produced hydrogen with a rate of 1495 μmol/g.h. The degradation kinetics followed a pseudo-first-order model at low concentrations and a Langmuir-Hinshelwood model at higher levels, emphasizing the role of CNTs in enhancing charge transfer and degradation efficiency. The enhanced photocatalytic activity is attributed to the synergistic effects of CuO and CNTs, promoting efficient charge separation, extended visible light absorption, and faster electron transport. Stability tests confirmed the composite's durability, retaining 91 % efficiency after four cycles.
在本文中，通过共沉淀法合成了SrTiO/CuO/CNT纳米复合材料，以实现更好的可见光光催化性能。结合场发射扫描电子显微镜（FESEM）、漫反射光谱（DRS）、光致发光（PL）光谱和X射线光电子能谱（XPS）的X射线衍射（XRD）分析证实，CuO和CNT成功整合到SrTiO纳米颗粒中。这些改性导致粒径减小，同时将带隙缩小至2.85 eV。它们提高了电荷能力，降低了PL强度，增加了光电流密度，并降低了电荷转移电阻。通过水分解对有机污染物降解和产氢的光催化性能进行了评估。该纳米复合材料在60分钟内实现了亚甲基蓝（MB）的完全降解，对甲基橙（MO）和罗丹明B（RhB）等其他污染物也具有高效降解能力。使用清除剂方法对机理进行的研究确定了II型电荷转移，同时表明超氧自由基是主要的反应物种。该纳米复合材料产氢速率为1495 μmol/g·h。降解动力学在低浓度下遵循准一级模型，在较高浓度下遵循Langmuir-Hinshelwood模型，强调了CNT在增强电荷转移和降解效率方面的作用。增强的光催化活性归因于CuO和CNT的协同效应，促进了有效的电荷分离、扩展的可见光吸收和更快的电子传输。稳定性测试证实了该复合材料的耐久性，四个循环后仍保留91%的效率。
