Indrajit Sinha

Indian Institute of Technology (BHU), India

Title: Visible light Zn and Ni-doped Ag2O photocatalysts

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Biography

My current research interests are integrating experimental and computational techniques for a proper understanding of adsorption and catalysis/photocatalysis mechanisms. Recently, we have used molecular dynamics and DFT calculation in conjunction with thorough experimental investigations for understanding the semiconductor photocatalysis and adsorption mechanisms involved. The emphasis is on the development of novel composite and doped photocatalysts for target or particular reactions.

Research publications: 79

Ph.D.’s supervised: 7

Google Scholar h-index: 19

Abstract

Doping can enhance charge separation and the photostability of a photocatalyst. We present our recent investigations on the effect of cation (Zn and Ni) doping on the photocatalytic properties of the narrow bandgap Ag2O semiconductor. The synthesis of Zn and Ni-doped Ag2O nanostructures followed a typical hydrothermal procedure. Zn-doping resulted in lattice expansion of Ag2O, indicating the occupation of an interstitial position by the dopant metal ion. In contrast, Ni-doping led to Ag2O lattice contraction due to the smaller Ni substituting the larger Ag atom. The XRD characterization results were supported by the density functional theory (DFT) formation energy calculations. The bandgap of the Ag2O increased to 1.65 eV for 5-mol percent Zn-doping. Contrary to this, the Ag2O nanoparticle bandgap showed a slight contraction after Ni-doping. Doping Ag2O by the higher oxidation state cations enhanced the chemisorbed oxygen on the surfaces of the prepared nanoparticles. XPS analysis also indicated a shift in the valence band position of the photocatalyst. These doped Ag2O nanoparticles were useful in the photocatalysis of methyl orange degradation and CIP degradation under visible light irradiation.