Synthesis Photo Physical Properties and Applications of Nitrogen doped Carbon Dot

Abstract

The thesis addressed various strategies to regulate the photo-physical property and applicability of carbon dots (CDs) by heteroatom (especially Nitrogen(N)) incorporation approach. This thesis pursues a detailed analysis of the structural and optical properties of newly developed N-doped CDs (NCDs). Till now, the source of emission property of CDs is not explained properly, which is the main inspiration of the thesis to explore each detailed photo-physical characteristic of synthesized NCDs and executed the same in the sensing and biological platform. The systematic development of carbon-based quantum dots (carbon and graphene quantum dots) as potential luminescent materials is discussed along with their synthesis procedures, photoluminescent properties, and vast application. The specific detection of Pb2+ and ClO¯ by using surface-functionalized graphene quantum dot (F-GQD) is successfully achieved. The surface modification of graphene quantum dot (GQD) was done by a simple coupling reaction between 2,6-diaminopyridine moiety, and GQD which is further applied to imaging and recognition of ClO¯ in living cells and Pb2+detection occurred by aggregation induced emission enhancement manner whereas the ClO¯ detection consists of energy migration through H-bonding network between amino group of F-GQD and ClO¯. Again, the hydrothermal synthesis was considered for synthesis of highly blue emissive NCDs (quantum yield 22.7 % in an aqueous medium) from 3,6-diaminoacridine hydrochloride and L-aspartic acid for the detection of two analytes i.e., vitamin-B12 and bilirubin. Here also, the mechanism of detection of two analytes are totally opposite in nature. For vitamin-B12, inner filter effect plays the key role for emission suppression, whereas, H-bonding induced energy transfer was operated for detection of bilirubin. Moreover, the NCD was further applied in living cell imaging and successfully recognize vitamin-B12 in HeLa cells. We cover a brief detection strategy to recognize 4-nitroaniline (4-NA) by two different emi