Imboon Tanawat, Sugio Kazuya, Khumphon Jeerawan, Sridawong Laksanaphon, Mangala Gowri Veeramani, Yamada Keisuke, Shima Mutsuhiro, Thongmee Sirikanjana
Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
Research Unit of Applied Physics for Agriculture and Medicine: APAM, Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
ACS Omega. 2025 Aug 1;10(31):34571-34587. doi: 10.1021/acsomega.5c03213. eCollection 2025 Aug 12.
This study investigates the synthesis and characterization of Fe-ZnO/GO composites aimed at enhancing magnetic characteristics and improving the photocatalytic degradation of organic contaminants. Reflux condensation was used to synthesize Fe-doped ZnO, which was then mixed with graphene oxide (GO) to form a composite. Energy-dispersive X-ray spectroscopy and electron microscopy demonstrated homogeneous Fe-ZnO dispersion on GO sheets. In contrast, a structural study using X-ray diffraction confirmed the wurtzite phase of ZnO, with peak changes indicative of Fe integration. UV-visible spectroscopy demonstrated an expanded absorption range and a reduced bandgap of 2.76 eV in Fe-ZnO/GO compared to 3.06 eV in ZnO. Photoluminescence studies showed decreased electron-hole recombination due to GO's electron-accepting properties. The Fe-ZnO/GO composite outperformed Fe-ZnO (97.46%) and ZnO (58.16%) in terms of photocatalytic degradation efficiency for Rhodamine B under UV light, achieving 99.32% degradation within 24 h. A first-order rate constant of 0.2093 h, 5.80 times greater than ZnO, was found via kinetic analysis. The combined effects of GO for improved charge separation and reactive oxygen species generation, and Fe doping for enhanced light absorption, were attributed to the superior performance. Vibrating sample magnetometry confirmed the ferromagnetic behavior of Fe-ZnO/GO, with a saturation magnetization of 7.69 × 10 emu/g. This indicates that the material can be easily separated using a magnetic field, which is beneficial for recycling and reuse. The enhanced photocatalytic activity, structural stability, and reusability make Fe-ZnO/GO a promising candidate for environmental remediation. However, further improvement in its visible-light response and long-term stability is needed for large-scale water treatment applications.
本研究旨在研究铁掺杂氧化锌/氧化石墨烯（Fe-ZnO/GO）复合材料的合成与表征，以增强其磁特性并改善对有机污染物的光催化降解性能。采用回流冷凝法合成铁掺杂氧化锌，然后将其与氧化石墨烯（GO）混合形成复合材料。能量色散X射线光谱和电子显微镜显示Fe-ZnO在氧化石墨烯片上均匀分散。相比之下，利用X射线衍射进行的结构研究证实了氧化锌的纤锌矿相，其峰位变化表明铁已整合其中。紫外可见光谱表明，与氧化锌的3.06 eV相比，Fe-ZnO/GO的吸收范围扩大，带隙减小至2.76 eV。光致发光研究表明，由于GO的电子接受特性，电子-空穴复合减少。在紫外光下，Fe-ZnO/GO复合材料对罗丹明B的光催化降解效率优于Fe-ZnO（97.46%）和氧化锌（58.16%），在24小时内降解率达到99.32%。通过动力学分析发现，其一级反应速率常数为0.2093 h，比氧化锌大5.80倍。GO改善电荷分离和活性氧生成的综合作用以及铁掺杂增强光吸收的作用，被认为是其优异性能的原因。振动样品磁强计证实了Fe-ZnO/GO的铁磁行为，其饱和磁化强度为7.69×10 emu/g。这表明该材料可以很容易地通过磁场分离，这有利于回收和再利用。增强的光催化活性、结构稳定性和可重复使用性使Fe-ZnO/GO成为环境修复的有前途的候选材料。然而，对于大规模水处理应用，需要进一步改善其可见光响应和长期稳定性。
