Browsing by Author "Bhat, D. Krishna"

Filter results by typing the first few letters
Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Biopolymer Electrolytes
    (2018) Sudhakar, Y.N.; Bhat, D. Krishna; Selvakumar, M.
  • Thumbnail Image
    Item
    Graphene - Metal Tungstate Nanocomposites for Catalytic Applications
    (National Institute of Technology Karnataka, Surathkal, 2018) Sadiq M, Mohamed Jaffer; Bhat, D. Krishna
    The research thesis entitled ‘Graphene - Metal Tungstate Nanocomposites for Catalytic Applications’ deals with the synthesis, characterization and studies on catalytic properties of some graphene - metal tungstate nanocomposites. The work describes successful synthesis of five different kinds of novel graphene-metal tungstate based nanocomposites namely, NRGO/ZnWO4/Fe3O4, NRGO/NiWO4/ZnO, NRGO/CoWO4/Fe2O3, NRGO/FeWO4/Fe3O4 and NRGO/BaWO4/g-C3N4 using facile microwave irradiation method. All the synthesized nanocomposites were carefully characterized for their elemental composition, structural, morphological and optical properties by employing appropriate techniques such as, XRD, SEM, FESEM, TEM, HRTEM, BET, XPS, DRS, Raman, FTIR, UVVis and PL spectroscopies. Thereafter, each nanocomposite was investigated for its catalytic efficiency towards, (i) The photodegradation of methylene blue dye under the visible light irradiation, (ii) The reduction of 4-Nitrophenol to 4-Aminophenol by sodium borohydride in aqueous media and (iii) The electrocatalytic hydrogen evolution reaction in alkaline media. The synthesized nanocomposites exhibit high catalytic activity due to the synergistic effects of the components of the nanocomposite materials. The reusability of the catalysts in all the above processes is also good. Therefore, the observed results suggest that these novel graphene - transition metal tungstate based ternary nanocomposites are potential candidates as multifunctional catalysts in the field of clean energy and environmental applications.
  • Thumbnail Image
    Item
    Perovskite Alkaline Earth Titanates Based Nanomaterials as Photocatalysts
    (National Institute of Technology Karnataka, Surathkal, 2023) B, Harsha; Bhat, D. Krishna
    The research thesis entitled ‘Perovskite alkaline earth titanates based nanomaterials as photocatalysts’ deals with the synthesis, characterization and photocatalytic studies of some doped perovskite alkaline earth titanates and porous graphene-perovskite alkaline earth titanate nanocomposites. The present study reports the successful synthesis of seven different series of novel perovskite alkaline earth titanate-based materials namely, Rh-doped SrTiO3, V-doped SrTiO3, porous graphene-SrTiO3 nanocomposite (PGST), Rh-doped BaTiO3, porous graphene-BaTiO3 nanocomposite (PGBT), V-doped CaTiO3 and porous graphene-CaTiO3 nanocomposite (PGCT) using facile solvothermal/hydrothermal method. All the synthesized materials were carefully characterized for their elemental composition, structural, morphological, and optical properties by employing appropriate techniques such as XRD, FESEM, EDS, TEM, HRTEM, Raman Spectroscopy, XPS, BET, DRS, and PL spectroscopy. Thereafter, each material was investigated for its catalytic efficiency towards the degradation of methylene blue dye under visible light irradiation. The synthesized materials exhibited enhanced photocatalytic efficiency which could be attributed to the efficient visible light harvesting capacity and reduced rate of recombination of photoinduced charges.