Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, Rajasthan, India.
Department of Chemistry, Indian Institute of Petroleum and Energy, Visakhapatnam, 530003, Andhra Pradesh, India.
Chemosphere. 2022 Jan;287(Pt 2):132105. doi: 10.1016/j.chemosphere.2021.132105. Epub 2021 Aug 31.
A simpler approach of functionalization for the fabrication of thiourea-functionalized-Graphene Aerogel (t-GA) is described here. Graphene Aerogel (GA) was synthesized from bio-mass, which on a simpler oxidative treatment get converted to its water-soluble version due to the impregnation of several oxygenous functionalities like carboxylic, hydroxyl, etc. Further, these carboxylated groups have been functionalized with the molecules of thiourea using the long known dicyclohexylcarbodiimide (DCC) as a coupling agent. The as-synthesized t-GA shows bright yellow fluorescence with a quantum yield of ~3% and holds the high-aqueous solubility and photostability. The fluorescence property of t-GA has been used here for the specific and selective sensing of toxic lead (Pb(II)) metal ions from the used many other metal ions via the fluorescence quenching and showed a limit of detection ~7.3 nM. Further, the mechanism for selective sensing was studied in detail and found to be preferable via ligand to metal charge transfer quenching mechanism. The cyclic voltammetry studies supported the selective sensing of Pb(II). Moreover, t-GA has also been studied for the sensing of hydrogen peroxide and as a yellow fluorescent ink.
这里描述了一种用于制备硫脲功能化石墨烯气凝胶（t-GA）的更简单的功能化方法。石墨烯气凝胶（GA）是由生物质合成的，通过简单的氧化处理，由于浸渍了几种含氧官能团，如羧基、羟基等，其水溶性版本会得到转化。进一步，这些羧基基团通过使用久负盛名的二环己基碳化二亚胺（DCC）作为偶联剂与硫脲分子进行功能化。所合成的 t-GA 具有明亮的黄色荧光，量子产率约为 3%，并且具有高的水溶解度和光稳定性。t-GA 的荧光性质已被用于通过荧光猝灭来特异性和选择性地检测有毒的铅（Pb(II)）金属离子，与许多其他金属离子相比，其检测限约为 7.3 nM。此外，详细研究了选择性传感的机制，发现通过配体到金属电荷转移猝灭机制是优选的。循环伏安法研究支持对 Pb(II)的选择性传感。此外，还研究了 t-GA 对过氧化氢的传感作用以及作为黄色荧光墨水的应用。
