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Large Scale synthesis of nanomaterials and processing of thin films is imperative for employing in energy harvesting applications. Traditional methods to process thin films such as rapid thermal annealing and chemical methods have limitations such as flexible substrate, hazardous waste, long processing time and high costs. Herein, I report the instantaneous novel photonic processing technique that uses high energy light from a xenon lamp to cure thin films. Moreover, I also report on the design and build of vacuum chamber to process the thin films under controlled pressure. I used spray coating for thin film deposition on silicon wafers for transition metal oxides and silicon/germanium precursors. To make thin films of 2D material (MXenes) we used doctor blade. This dissertation explores the nucleation and growth of thin films under different processing conditions which is important to scale up the thin film processing methods over large scale with precise control over the properties of the thin films.
The first project is synthesis of silicon and germanium-based (GeOx and SiOx ) nanoparticles using xenon lamp flash curing with total fluence 80 Jcm-2. The results showed synthesis of ester functionalized GeOx and SiOx nanostructures. The increase in number of pulses resulted in nanoparticle size change from ~48 nm to ~11 nm. The second project is design and building of a vacuum chamber to process the thin films in vacuum, inert and reactive gas environment. The chamber can be attached to the PulseForge systema and is capable of curing the thin films up to 4 atm. pressure. This chamber was then employed for next projects. In the third project, we intercalated MXenes with PDMS and process them with photonic curing to increase the d-spacing and removal of excess PDMS after intercalation respectively. The d-spacing of MXenes increase from 1 nm to up to 26 nm. The samples processed in the chamber in forming gas showed the conversion of PDMS into silicon carbide-based materials within the layers of MXenes. In the fourth project, the bimetallic transition metal oxide (TMO) electrodes were prepared for supercapacitors. The project aims to study the nucleation and growth of the TMO under different curing conditions. The results showed that the retention of the electrodes can be increased from 14% to 88% for 6k cycles if the gas environment is changed from argon to forming gas.