Tunable Luminescence of Graphene Based Nanomaterials: Role of Surfactants and Macromolecules

Abstract

The present thesis entitled “Tunable Luminescence of Graphene Based Nanomaterials: Role of Surfactants and Macromolecules” addresses the synthesis of graphene based nano materials like graphene oxide (GO), chemically modified graphene oxide (CM-GO), graphene oxide polyaniline (GO-PANI) nanocomposite with tunable photoluminescence nature (PL). The role surfactants like sodium dodecyl sulphate (SDS), cetyl trimethyl ammonium bromide (CTAB) has been also described to modulate the PL of GO. This thesis comprises of eight chapters. Chapter 1 deals with the general introduction and brief description of the summary of the research work. The motivation, objectives and plan of the present investigation are also stated in this chapter. Chapter 2 deals with the properties and structure of graphene, the different method of synthesis of graphene existing in literature and the literature review on the photoluminescence properties of GO and GO based nanomaterials till 2020. Chapter 3 describes the method of synthesis with the characterization of GO, CM-GO and GO-PANI nano-composite. Chapter 4 discusses the effect of pH on the PL properties of GO-PANI nano-composite. The interaction between polyanilne and GO changes with the change in pH, which strongly affects the PL properties of the GO-PANI nanocomposite. Chapter 5 includes the study of PL of GO in the aqueous medium in the presence of different concentration of surfactants (SDS and CTAB).The mode interaction between GO and surfactant strongly depends on the pH of the medium which modulates the band gap of GO are described in this chapter. Chapter 6 includes the study of PL of GO-PANI in the aqueous medium in the presence of an anionic surfactant (SDS) at both acidic and alkaline medium. The interaction between GO-PANI and SDS is different in different pH, which modulates the PL of the GO-PANI nano-composite material. Chapter 7 describes the PL properties of both GO and CM-GO in aqueous medium with proper explanation of the origin of the luminescence. The modulation of luminescence both GO and CM-GO by changing concentration also described in this chapter. The conclusion of the research work along with the future prospects obtained from this thesis are presented in Chapter 8.