Gong Lei, Li Jiaxin, Jin Rui, Li Menghao, Peng Jiajie, Zhu Jie
National-Local Joint Engineering Research Center of Biomass Refining and High-Quality Utilization, Institute of Urban & Rural Mining, Changzhou University, Changzhou 213164, China.
School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
Molecules. 2025 Jul 28;30(15):3155. doi: 10.3390/molecules30153155.
In this study, we report the development of a novel magnetized coal fly ash-supported nano-silver composite (AgNPs/MCFA) for dual-functional applications in wastewater treatment: the efficient degradation of methyl orange (MO) dye and broad-spectrum antibacterial activity. The composite was synthesized via a facile impregnation-reduction-sintering route, utilizing sodium citrate as both a reducing and stabilizing agent. The AgNPs/MCFA composite was systematically characterized through multiple analytical techniques, including Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and vibrating sample magnetometry (VSM). The results confirmed the uniform dispersion of AgNPs (average size: 13.97 nm) on the MCFA matrix, where the formation of chemical bonds (Ag-O-Si) contributed to the enhanced stability of the material. Under optimized conditions (0.5 g·L AgNO, 250 °C sintering temperature, and 2 h sintering time), AgNPs/MCFA exhibited an exceptional catalytic performance, achieving 99.89% MO degradation within 15 min (pseudo-first-order rate constant = 0.3133 min) in the presence of NaBH. The composite also demonstrated potent antibacterial efficacy against (MIC = 0.5 mg·mL) and (MIC = 2 mg·mL), attributed to membrane disruption, intracellular content leakage, and reactive oxygen species generation. Remarkably, AgNPs/MCFA retained >90% catalytic and antibacterial efficiency after five reuse cycles, enabled by its magnetic recoverability. By repurposing industrial waste (coal fly ash) as a low-cost carrier, this work provides a sustainable strategy to mitigate nanoparticle aggregation and environmental risks while enhancing multifunctional performance in water remediation.
在本研究中，我们报道了一种新型的磁化粉煤灰负载纳米银复合材料（AgNPs/MCFA）的开发，用于废水处理中的双重功能应用：高效降解甲基橙（MO）染料和广谱抗菌活性。该复合材料通过简便的浸渍-还原-烧结路线合成，使用柠檬酸钠作为还原剂和稳定剂。通过多种分析技术对AgNPs/MCFA复合材料进行了系统表征，包括傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线衍射（XRD）和振动样品磁强计（VSM）。结果证实了AgNPs（平均尺寸：13.97 nm）在MCFA基质上的均匀分散，其中化学键（Ag-O-Si）的形成有助于提高材料的稳定性。在优化条件（0.5 g·L AgNO，250°C烧结温度和2 h烧结时间）下，AgNPs/MCFA表现出优异的催化性能，在NaBH存在下15分钟内实现了99.89%的MO降解（准一级速率常数 = 0.3133 min）。该复合材料还对大肠杆菌（MIC = 0.5 mg·mL）和金黄色葡萄球菌（MIC = 2 mg·mL）表现出强大的抗菌效果，这归因于膜破坏、细胞内物质泄漏和活性氧的产生。值得注意的是，由于其磁回收性，AgNPs/MCFA在五个重复使用周期后仍保留>90%的催化和抗菌效率。通过将工业废料（粉煤灰）重新用作低成本载体，这项工作提供了一种可持续的策略，以减轻纳米颗粒聚集和环境风险，同时提高水修复中的多功能性能。
