Kaviyarasu K
UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology Laboratories, School of Interdisciplinary Research and Graduate Studies, College of Graduate Studies, University of South Africa (UNISA), Roodepoort, Johannesburg, South Africa.
Microsc Res Tech. 2025 Jan;88(1):73-91. doi: 10.1002/jemt.24672. Epub 2024 Aug 27.
As a result of their unique and novel properties, nanocomposites have found applications in a wide variety of fields. The purpose of this study is to demonstrate the ability to synthesize nanoparticles consisting of zinc oxide (ZnO) and graphene oxide (GO) via sol-gel techniques. An x-ray diffractometer (XRD) as well as a UV-visible spectrometer were used to determine the crystalline and optical characteristics of the prepared samples. A hexagonal wurtzite crystal structure was observed in both pure ZnO nanoparticles and those that contain GO based on XRD results. It was estimated that the average crystallite size is based on the broadening of x-ray lines. In comparison with pure ZnO, the antimicrobial properties were enhanced when GO was incorporated with ZnO. In addition, experiments on the absorption edge indicated the presence of a red shift as a result of the incorporation of GO. When GO is incorporated in quantitative amounts, the bandgap value of pure ZnO decreased. FTIR spectra exhibit a band of absorption at 486 cm, which confirms Zn-O stretching in both samples. SEM images reveal a random pattern of structural features on the surface of the prepared samples. According to the EDX spectrum, pure GO nanoparticles and those doped with ZnO contain 61%-64% zinc and 32%-34% oxygen, respectively. When annealed at a higher temperature, ZnO NPs produced more H with a narrower bandgap than before annealing. In addition, methyl blue (MB) was used as an example of an organic compound in order to investigate the potential photocatalytic properties of nanoparticles with ZnO doped GO. In addition to DPPH assays, ZnO nanoparticles and ZnO doped GO nanoparticles were tested for their ability to scavenge free radicals. Comparing ZnO doped GO NPs with pure ZnO, these nanoparticles showed increased antioxidant activity. Based on the increased zone of inhibition observed for pure ZnO and ZnO doped GO (5, 10, 50, and 100 mg/mL), the antibacterial activity of pure ZnO and ZnO doped GO is concentration dependent. A detailed discussion of the results of the study demonstrated that ZnO doped GO and pure ZnO are toxic in different ways depending on how long they survive in degreased Zebrafish embryos and how fast they decompose. RESEARCH HIGHLIGHTS: The scope of the manuscript was under the results of the study confirmed that both nanoparticles exhibited concentration dependent antioxidative activity. Determined that 89% of methyl orange dye can be degraded photocatalytically. ZnO nanoparticles were found to be 74.86% antioxidant at a concentration of 50 g/mL in the present study. At a concentration of 50 g/mL, ZnO doped GO NPs showed 79.1% antioxidant activity. Photocatalytic degradation mechanism scheme is implicit in the photoexcited charge carrier transportation path is observed for all the samples. Survival rate of zebrafish embryos was shown to decrease with increasing concentrations of ZnO and zinc oxide plus GO nanoparticles.
由于其独特新颖的性质,纳米复合材料已在众多领域得到应用。本研究的目的是证明通过溶胶 - 凝胶技术合成由氧化锌(ZnO)和氧化石墨烯(GO)组成的纳米颗粒的能力。使用X射线衍射仪(XRD)以及紫外 - 可见光谱仪来确定所制备样品的晶体和光学特性。基于XRD结果,在纯ZnO纳米颗粒以及含有GO的纳米颗粒中均观察到六方纤锌矿晶体结构。据估计,平均微晶尺寸基于X射线谱线的展宽。与纯ZnO相比,当GO与ZnO结合时,抗菌性能增强。此外,吸收边缘的实验表明由于GO的掺入存在红移。当定量掺入GO时,纯ZnO的带隙值降低。傅里叶变换红外光谱(FTIR)在486 cm处呈现吸收带,这证实了两个样品中Zn - O的伸缩振动。扫描电子显微镜(SEM)图像揭示了所制备样品表面结构特征的随机图案。根据能量散射X射线谱(EDX),纯GO纳米颗粒以及掺杂ZnO的纳米颗粒分别含有61% - 64%的锌和32% - 34%的氧。当在较高温度下退火时,ZnO纳米颗粒产生更多具有比退火前更窄带隙的H。此外,以甲基蓝(MB)作为有机化合物的示例,以研究掺杂ZnO的GO纳米颗粒的潜在光催化性能。除了二苯基苦味酰基自由基(DPPH)测定外,还测试了ZnO纳米颗粒和掺杂ZnO的GO纳米颗粒清除自由基的能力。将掺杂ZnO的GO纳米颗粒与纯ZnO相比,这些纳米颗粒显示出增强的抗氧化活性。基于对纯ZnO和掺杂ZnO的GO(5、10、50和100 mg/mL)观察到的抑菌圈增加,纯ZnO和掺杂ZnO的GO的抗菌活性与浓度有关。对研究结果的详细讨论表明,掺杂ZnO的GO和纯ZnO的毒性方式不同,这取决于它们在脱脂斑马鱼胚胎中的存活时间以及分解速度。研究亮点:该手稿的范围在于研究结果证实两种纳米颗粒均表现出浓度依赖性抗氧化活性。确定89%的甲基橙染料可被光催化降解。在本研究中,发现ZnO纳米颗粒在浓度为50 g/mL时抗氧化率为74.86%。在浓度为50 g/mL时,掺杂ZnO的GO纳米颗粒显示出79.1%的抗氧化活性。光催化降解机理隐含在所有样品观察到的光激发电荷载流子传输路径中。随着ZnO以及ZnO加GO纳米颗粒浓度的增加,斑马鱼胚胎的存活率降低。