@article{ajer20241222,
author={{Mugambi, Nelson and Ngaruiya, James Mbiyu and Mugo, Simon Waweru},
title={Enhancing the Performance of Titanium Dioxide Compact Layer on Epitaxial Graphene and Fluorine Tin Oxide Heterojunctions},
journal={American Journal of Energy Research},
volume={12},
number={2},
pages={40--46},
year={2024},
url={https://pubs.sciepub.com/ajer/12/2/2},
issn={2328-7330},
abstract={We report a facile synthesis of Titanium dioxide (TiO<SUB>2</SUB>) modified compact layers on Fluorine Tin oxide (FTO) and graphene employing the Sol gel Doctor Blade technique, optimized systematically for enhanced solar energy conversion applications. UV-VIS spectrophotometer, a Varian 7000e FTIR, a Scanning Kelvin Probe Microscope, and Hall Effect setup evaluated the as deposited and films subjected to 1 step, 2¡ãC/min and 1¡ãC/min annealing rates. FTIR revealed considerable absorption at low frequencies (less than 798 cm<SUP>-1</SUP>) in TiO<SUB>2</SUB> on graphene heterojunctions, confirming the occurrence of Ti-O and C-O-Ti bonds. The predominant anatase TiO<SUB>2</SUB> characteristic was found at 438 cm<SUP>-1</SUP>. The TiO<SUB>2</SUB> on graphene film annealed at 1 ¡ãC/min exhibited the lowest porosity (46%), as well as the highest dispersion energy (11.30 eV). As the annealing rates declined, so did the surface-to-volume energy loss ratio for all the annealed films. Graphene TiO<SUB>2</SUB> annealed at 1 <SUP>o</SUP>C/min had a lower VELF/SELF than TiO<SUB>2</SUB> on FTO, implying that an electron loses less energy when passing through the TiO<SUB>2</SUB> on graphene layer than it does in TiO<SUB>2</SUB><SUB> </SUB>on FTO. The light absorption coefficient ¦Á and electron diffusion coefficient D of TiO<SUB>2</SUB> on graphene improved to 4.637 x 10<SUP>3</SUP> and 1.485 x 10<SUP>-4</SUP><SUP> </SUP>(1 <SUP>o</SUP>C/min), respectively, whereas TiO<SUB>2</SUB> on FTO values increased to 4.221 x 10<SUP>3</SUP> and 1.251 x 10<SUP>-4</SUP> (1¡ãC/min), in that order, with decreasing annealing rates. Higher values of TiO<SUB>2</SUB> on graphene ¦Á and D indicate enhanced electron transition in the films. Hall Effect measurements on as-deposited and annealed TiO<SUB>2</SUB> on graphene films demonstrated higher conductivity as annealing rates decreased, which was attributed to film recrystallization induced by calcination. Smoluchowski smoothing model, reveal surface scan average work functions (¦Õ) and linear profile scan average work functions (¦Õ) ensemble variations in granular tilts and surface slopes explaining geographic variation and distribution. Local fluctuations in ¦Õ triggered by the spatially varying concentrations of electric dipole moments are intrinsic to atomic steps and influence ¦Õ. TiO<SUB>2</SUB> incorporation on graphene photoanode increased h<SUP>+</SUP>/e<SUP>-</SUP>separation, electron transport, and light absorption. The continuous conduction network on compact TiO<SUB>2</SUB> nanoparticles acts as an electron leakage barrier, and the porous structure has a large specific surface area.},
doi={10.12691/ajer-12-2-2}
publisher={Science and Education Publishing}
}