Department of Chemistry, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, 133203, Haryana, India.
Department of Chemistry, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, 133203, Haryana, India.
Environ Res. 2022 Dec;215(Pt 2):114245. doi: 10.1016/j.envres.2022.114245. Epub 2022 Sep 8.
Herein, we report a simple, low-temperature, ecofriendly synthesis of graphene oxide nanosheets (GONs). Graphite powder was treated with KMnO and a concentrated HSO/HPO mixture to synthesize GONs. The effects of various reaction conditions such as reaction time, temperature, amounts of cleaving agents (HSO/HPO), and oxidant (KMnO) were investigated. The synthesized GONs were examined by various techniques in order to investigate their characteristics. The best results of the synthesized GONs were observed at 35 °C within 10 h of reaction time having 8:2 ratios of HSO/HPO acid mixture. The main absorption peak in the UV-vis spectra of GONs was at 258 nm, which is due to the π-π* transition of the atomic CC bonds. The existence of stretching vibrations of C꞊O, O-H, C-H, and C-O in the Fourier transform infrared (FTIR) spectra verified the formation of GONs. Presence of a sharp peak at 2θ = 10° with an interlayer spacing distance of 0.88 nm in the observed XRD pattern revealed that the synthesized GONs were totally oxidized and that the interlayer spacing increased. The morphological investigations confirmed the formation of ultrathin, transparent, curly, and homogenous GONs. The synthesized GONs were applied as an adsorbent for the rapid uptake of four different pesticides viz.; Profenofos, Ethion, Cypermethrin, Thiamethoxam (TMX) from the pesticides spiked water samples. About 86% adsorption of Profenofos + Cypermethrin, and 50% adsorption of ethion and thiamethoxam took place within 20 min in presence of 10 mg GONs. In addition to this, the prepared GONs were tested for the antibacterial activity against four bacterial strains by agar well diffusion method. The synthesized GONs provide a significant inhibition for gram -positive (Bacillus subtilis, and Staphylococcus aureus) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. Moreover, the radical scavenging activities (RSA) of GONs were also checked and compared with Gallic acid as a standard. The obtained RSA of GONs was 60% in comparison to the 80% as of the standard Gallic acid at 1000 μg/mL concentration.
在这里，我们报告了一种简单、低温、环保的氧化石墨烯纳米片（GONs）合成方法。石墨粉与 KMnO 和浓 HSO/HPO 混合物反应合成 GONs。研究了各种反应条件（如反应时间、温度、裂解剂（HSO/HPO）和氧化剂（KMnO）的用量）的影响。通过各种技术对合成的 GONs 进行了测试，以研究其特性。在 35°C 下反应 10 小时，HSO/HPO 酸混合物的比例为 8:2，可获得合成 GONs 的最佳结果。GONs 的紫外-可见光谱中的主要吸收峰在 258nm 处，这是由于原子 CC 键的 π-π*跃迁所致。傅里叶变换红外（FTIR）光谱中存在的 C꞊O、O-H、C-H 和 C-O 的伸缩振动证实了 GONs 的形成。在观察到的 XRD 图谱中，2θ=10°处存在一个尖锐的峰，层间间距为 0.88nm，表明合成的 GONs 完全氧化，层间间距增大。形貌研究证实了超薄、透明、卷曲和均匀的 GONs 的形成。合成的 GONs 被用作吸附剂，从含有四种不同农药（如 Profenofos、Ethion、Cypermethrin 和 Thiamethoxam（TMX）的农药污染水样中快速吸附。在 10mg GONs 的存在下，Profenofos+Cypermethrin 的吸附率约为 86%，Ethion 和 Thiamethoxam 的吸附率约为 50%，吸附时间均为 20min。此外，还通过琼脂孔扩散法测试了制备的 GONs 对四种细菌菌株的抗菌活性。合成的 GONs 对革兰氏阳性（枯草芽孢杆菌和金黄色葡萄球菌）和革兰氏阴性（大肠杆菌和铜绿假单胞菌）细菌菌株具有显著的抑制作用。此外，还检查了 GONs 的自由基清除活性（RSA），并与作为标准的没食子酸进行了比较。在 1000μg/mL 浓度下，GONs 的 RSA 为 60%，而标准没食子酸的 RSA 为 80%。
