Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
2 results
Search Results
Item Photoelectrochemical studies on metal-doped graphitic carbon nitride nanostructures under visible-light illumination(MDPI, 2020) Reddy, I.; Jayashree, N.; Manjunath, V.; Kim, D.; Shim, J.Recently, the engineering of optical bandgaps and morphological properties of graphitic carbon nitride (g-C3N4) has attracted significant research attention for photoelectrodes and environmental remediation owing to its low-cost synthesis, availability of raw materials, and thermal physical–chemical stability. However, the photoelectrochemical activity of g-C3N4-based photoelectrodes is considerably poor due to their high electron–hole recombination rate, poor conductivity, low quantum efficiency, and active catalytic sites. Synthesized Ni metal-doped g-C3N4 nanostructures can improve the light absorption property and considerably increase the electron–hole separation and charge transfer kinetics, thereby initiating exceptionally enhanced photoelectrochemical activity under visible-light irradiation. In the present study, Ni dopant material was found to evince a significant effect on the structural, morphological, and optical properties of g-C3N4 nanostructures. The optical bandgap of the synthesized photoelectrodes was varied from 2.53 to 2.18 eV with increasing Ni dopant concentration. The optimized 0.4 mol% Ni-doped g-C3N4 photoelectrode showed a noticeably improved six-fold photocurrent density compared to pure g-C3N4. The significant improvement in photoanode performance is attributable to the synergistic effects of enriched light absorption, enhanced charge transfer kinetics, photoelectrode/aqueous electrolyte interface, and additional active catalytic sites for photoelectrochemical activity. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.Item Vanadium-doped graphitic carbon nitride for multifunctional applications: Photoelectrochemical water splitting and antibacterial activities(Elsevier Ltd, 2021) Reddy, I.N.; Reddy, L.V.; Jayashree, N.; Venkata Reddy, C.V.; Cho, M.; Kim, D.; Shim, J.Bulk graphitic carbon nitride (g-C3N4) exhibits limited water splitting efficiency due todrawbacks including high charge recombination rate, low electrical conductivity, poor quantum efficiency, and few adsorption and active catalytic sites. Herein, we report V-doped g-C3N4 nanoarchitectures prepared via direct calcination of urea and ammonium metavanadate. The obtained V-doped g-C3N4 nanostructures not only improved the visible light absorption property but also increased the charge separation and transportation, resulting in extremely enhanced water splitting activity. The structural, morphological, and optical analysis results confirmed the successful incorporation of V into the host g-C3N4 material, and electrochemical impedance spectroscopy measurements revealed the charge carrier dynamics. Compared to the pristine g-C3N4 photoelectrode, the optimized 0.3 mol% V-doped g-C3N4 photoelectrode showed a considerably higher photocurrent density (0.80 mA cm-2). The enhancement of the catalytic performance could be attributed to the synergistic effects of prolonged light absorption, improved transfer of electrons and holes, and extra active catalytic sites for water splitting. Further, the optimized 0.3 mol% V-doped g-C3N4 sample showed an antibacterial activity higher than that of the undoped photocatalyst. © 2020 Elsevier Ltd