Optoelectrical and Photochemical Investigation of 2D Nanomaterials and their Nanocomposites Fabricated by Laser Ablation in Liquid

Synthesis of In2Se3 nanocubes fabricated by laser ablation under DI water and its Field electron emission properties as well as the carrier dynamics were investigated successfully for the application of high current density cold cathode material. The morphological characterization carried out using field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) reveal that the nano-cubes have an average size of 70 nm. The X-ray diffraction and Raman analysis clearly imply the formation of pure and crystalline In2Se3 phase only, without any impurity phases, despite the laser ablation being carried out in aqueous medium. A superior FE property characterized by lower values of turn-on and threshold fields as compared to In2Se3 nanowires emitter and ability to deliver very large current density ~2656 μA/cm2 by applying the field of 9.7 V/μm. Transient absorption spectra reveals there are no deep trap levels, the electrons in nanocubes can be regards as mobile carriers through the hopping process and travel long distance in the absence of holes.
Carrier dynamics and photocatalytic performance of novel In2Se3/ZnO/Au-nanoparticle ternary composite system is investigated. The ternary photocatalytic system was fabricated using hydrothermal and laser ablation technique. The structural and physical characteristics have been studied by SEM, TEM, ultraviolet-visible (UV–Vis) spectrophotometry, and micro-Raman spectroscopy. The photocatalytic activity of the nanocomposites was estimated through the photocatalytic degradation utilizing organic dye of methylene blue in an aqueous solution. Results suggested that the ternary composite showed better photocatalytic performance compared with the pristine and binary composites.
Production of few layers graphene from graphite is fabricated by UV laser scanning method. Morphological, structural and optical properties were investigated by TEM, HRTEM, UV-Vis spectroscopy and Micro-Raman spectroscopy. The surface modification of graphite under different liquid environment was investigated by optical laser microscope. After laser scanning the holes in graphite surface becomes dipper and less wide. The laser scanning process is most effective process to remove the layers of the graphite plate. Dips and hill are modified after laser scanning.

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