Ismardi Abrar, Gunawan Theresia Deviyana, Suhendi Asep, Fathona Indra Wahyudin
Department of Engineering Physics, School of Electrical Engineering, Telkom University, Bandung, Indonesia.
Heliyon. 2024 May 18;10(11):e31565. doi: 10.1016/j.heliyon.2024.e31565. eCollection 2024 Jun 15.
The presence of heavy metals often causes significant health risks, particularly cadmium, which is known for its high toxicity. In this study, a glassy carbon electrode was successfully modified by incorporating ZnO-PVA-Graphene nanocomposite, leveraging the excellent electrical properties and electron mobility of the material. Comprehensive material analysis, including XRD, confirmed that ZnO maintained its hexagonal wurtzite crystal structure despite the addition of graphene. Moreover, FESEM analysis showed that increasing graphene concentration led to a reduction in ZnO particle size by 85, 68, and 52 nm, respectively, accompanied by a decrease in band gap energy, as verified by UV-Vis measurements. Photoluminescence tests were also conducted and the result showed a noticeable blue shift in ZnO-PVA-Graphene nanocomposites compared to ZnO-PVA, specifically in the near band-edge (NBE) UV emission within the 374-379 nm wavelength range. Through I-V characterization, the optimal graphene concentration for cadmium detection was identified as 1.5 wt% in ZnO-PVA-Graphene nanocomposites, showing an approximate ohmic response. Meanwhile, square-wave voltammetry analysis of cadmium concentrations ranging from 0 to 80 ppm produced a coefficient of determination of 0.98926 and a Limit of Detection (LOD) of 9.88 ppm. These results showed the significant potential of ZnO-PVA-Graphene nanocomposites as a promising material for further development as an effective electrode modifier, enhancing the sensitivity of detection systems.
重金属的存在常常会带来重大的健康风险，尤其是镉，它以高毒性而闻名。在本研究中，通过掺入ZnO-PVA-石墨烯纳米复合材料成功修饰了玻碳电极，利用了该材料优异的电学性能和电子迁移率。包括XRD在内的综合材料分析证实，尽管添加了石墨烯，ZnO仍保持其六方纤锌矿晶体结构。此外，FESEM分析表明，随着石墨烯浓度的增加，ZnO粒径分别减小了85、68和52nm，同时带隙能量降低，这通过紫外-可见测量得到了验证。还进行了光致发光测试，结果表明与ZnO-PVA相比，ZnO-PVA-石墨烯纳米复合材料有明显的蓝移，特别是在374-379nm波长范围内的近带边（NBE）紫外发射中。通过I-V表征，确定了ZnO-PVA-石墨烯纳米复合材料中用于镉检测的最佳石墨烯浓度为1.5wt%，显示出近似的欧姆响应。同时，对0至80ppm镉浓度的方波伏安分析得出的决定系数为0.98926，检测限（LOD）为9.88ppm。这些结果表明，ZnO-PVA-石墨烯纳米复合材料作为一种有前景的材料，有潜力进一步开发成为有效的电极修饰剂，提高检测系统的灵敏度。
