Magagula Lindokuhle P, Masemola Clinton M, Motaung Tshwafo E, Moloto Nosipho, Linganiso-Dziike Ella C
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Braamfontein 2050, South Africa.
DSI/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Braamfontein 2050, South Africa.
Molecules. 2024 Dec 30;30(1):110. doi: 10.3390/molecules30010110.
The demand for reliable, cost-effective, room temperature gas sensors with high sensitivity, selectivity, and short response times is rising, particularly for environmental monitoring, biomedicine, and agriculture. In this study, corncob waste-derived activated carbon (ACC) was combined with CuO nanoparticles and polyvinyl alcohol (PVA) to fabricate ACC/PVA/CuO composites with CuO loadings of 5, 10, and 15 wt.%. The CuO nanoparticles (average size: 21.79 ± 9.88 nm) were successfully incorporated into the ACC matrix, as confirmed by TEM, XRD, and N adsorption-desorption analyses. Increasing CuO content reduced the specific surface area due to pore blockage but enhanced the composites' ethanol sensing performance. The ACC/PVA/CuO (15 wt.%) sensor exhibited the highest response and fastest recovery times (125 s and 130 s, respectively, at 100 ppm ethanol), outperforming other composites and pristine ACC. This improvement was attributed to surface defects and increased active sites promoting vapor adsorption and diffusion. These results demonstrate the potential of ACC/PVA/CuO as an effective ethanol sensor at room temperature.
对于具有高灵敏度、选择性和短响应时间的可靠、经济高效的室温气体传感器的需求正在上升，特别是在环境监测、生物医学和农业领域。在本研究中，将玉米芯废弃物衍生的活性炭（ACC）与氧化铜纳米颗粒和聚乙烯醇（PVA）相结合，制备了氧化铜负载量为5 wt.%、10 wt.%和15 wt.%的ACC/PVA/CuO复合材料。通过透射电子显微镜（TEM）、X射线衍射（XRD）和氮吸附-脱附分析证实，氧化铜纳米颗粒（平均尺寸：21.79 ± 9.88 nm）成功地掺入到ACC基体中。由于孔堵塞，氧化铜含量的增加降低了比表面积，但提高了复合材料的乙醇传感性能。ACC/PVA/CuO（15 wt.%）传感器表现出最高的响应和最快的恢复时间（在100 ppm乙醇浓度下分别为125 s和130 s），优于其他复合材料和原始ACC。这种改善归因于表面缺陷和活性位点的增加，促进了蒸汽吸附和扩散。这些结果证明了ACC/PVA/CuO作为室温下有效的乙醇传感器的潜力。
