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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 LtdItem Photoelectrochemical water oxidation kinetics and antibacterial studies of one-dimensional SiC nanowires synthesized from industrial waste(Springer Science and Business Media Deutschland GmbH, 2021) Reddy, I.N.; Sreedhar, A.; Pallavolu, M.R.; Reddy, L.V.; Cho, M.; Kim, D.; Jayashree, N.; Shim, J.Silicon wafers are significantly utilized in integrated circuits and memory devices for the fabrication of novel semiconductor devices. As a result, a substantial amount of silicon wastes are generated every year. But recycling process of pure silicon waste is expensive with an additional problem related to chemical waste generation. Thus, the possibility of inevitable silicon waste conversion into potential nanostructures is not only beneficial for the semiconductor industry but also resolves current e-waste pollution. Hence, we successfully achieved hexagonal silicon carbide (SiC) nanowires under a strategic combination of waste silicon wafers and graphite powder by robust high-energy ball milling and heat treatment approaches. Structural, morphological, chemical, and optical properties of SiC nanowires are systematically studied by XRD, SEM, TEM, XPS, and optical absorbance. This facile experimental technique recognized the value of SiC nanowire generation for exploring multifunctional photoelectrochemical (PEC) water splitting and antibacterial activity. Accordingly, SiC nanowires achieved a photocurrent density of about 0.21 mA cm?2 vs. Ag/AgCl, which demonstrates enhanced light absorption capacity under reduced charge carrier recombination. Moreover, SiC nanowires prevailed decrement in the charge carrier resistance (27.53 ?) under light state compared to the dark state (26.76 ?). Specifically, potentiodynamic studies revealed superior exchange current density (? 3.17 mA cm?2), Tafel slope (80.1 mV dec?1), and limiting diffusion current density (? 1.49 mA cm?2) under light state than the dark state. Also, these results are certainly applicable for superior antibacterial activity against E. coli and L. monocytogenes about 90% and 75% under visible light, respectively. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.