碳量子点(CQDs)由于其低毒性,近年来已成为碳纳米结构家族中最有前途的纳米材料之一,简单的合成方法,独特的荧光发射,良好的光稳定性,优良的水溶性,高比表面积和优异的电子性能。因此,它们已被广泛应用,包括荧光传感,电化学传感,生物成像,药物输送,抗菌研究,抗氧化剂,和光催化。CQDs由于其独特的光化学特性而引起了人们对传感应用的极大兴趣,电化学和电化学发光特性。它们表现出激发波长依赖性或非依赖性光致发光(PL)行为,高量子产率,和有希望的与分析物的结合能力,这使它们成为在基于PL的传感平台中使用的理想候选者。在农田中过度使用农用化学品会污染环境,并对水生和人类生命产生潜在的不利健康影响。由于很少有监测技术可用于感测此类有害物质,迫切需要开发一种方便的传感器,环境中农药残留的快速现场检测和定量。最近已经发表了几种基于CQD的荧光团,用于采用静态或动态猝灭过程来检测农用化学品残留物。传感过程中涉及的关键猝灭机制包括FRET,PET和IFE。本综述的第一部分旨在全面概述表征CQD的各种技术,例如UV-vis。,FT-IR,PL,XRD,NMR,TEM,TGA,XPS和拉曼分析。此外,本文还总结了CQDs作为不同介质中农药残留物的荧光传感器的应用。传感器的LOD值和快速动作证明了这些方法相对于常规分析程序的显着优势。
Carbon quantum dots (CQDs) have emerged as one of the most promising nanomaterials in the carbon nanostructures family in recent years due to their low toxicity, simple synthetic methods, unique fluorescence emission, good photostability, excellent water solubility, high specific surface areas and outstanding electronic properties. They have thus been employed in a wide range of applications, including fluorescent sensing, electrochemical sensing, bioimaging, drug delivery, antimicrobial studies, antioxidants, and photocatalysis. CQDs drawn great interest in sensing applications due to their unique photochemical, electrochemical and electrochemiluminescence properties. They exhibit excitation wavelength-dependent or -independent photoluminescence (PL) behaviour, high quantum yield, and promising binding ability with analytes, which make them an ideal candidate for use in PL based sensing platforms. Excessive use of agrochemicals in farm fields can pollute the environment and have potentially adverse health effects on aquatic and human life. Since there are very few monitoring techniques are available for sensing such harmful substances, there is an urgent need to develop a sensor for the facile, rapid and on-site detection and quantification of agrochemical residues in the environment. Several CQD-based fluorophores for detecting agrochemical residues employing static or dynamic quenching processes have recently been published. The key quenching mechanisms involved in the sensing process include FRET, PET and IFE. The first part of this
review intends to provide a comprehensive overview of various techniques to characterize CQDs such as UV-vis., FT-IR, PL, XRD, NMR, TEM, TGA, XPS and Raman analysis. In addition application of CQDs as fluorescent sensors for agrochemical residue in different media are summarized in this reiew. The LOD values and rapid action of the sensor demonstrates significant advantages of these methods over conventional analytical procedures.