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arXiv · 1906.11178

Hopping mechanisms, photoluminescence studies toward highly efficient UV-responsive Pr2MgTiO6 photocatalyst

Moumin Rudra·T. K. Bhowmik·H. S. Tripathi·R. A. Kumar·R. Sutradhar·T. P. Sinha
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Abstract

Titanium based-perovskites have got surprising attraction due to their environmentfriendly photocatalysts behavior. The Rietveld refinement of X-ray diffraction (XRD) pattern authenticates the orthorhombic Pnma structure of Pr2MgTiO6 (PMT). The Pr3+-Ti4+ intervalence charge transfer process plays an important role inside PMT. The dc conductivity shows a change in the hopping mechanism from nearest-neighbor hopping to a variable range hopping due to the activation energy reduction. This change in the hopping mechanism is well supported by both the relaxation time and impedance data in PMT. The constant phase element (CPE) model is utilized to fit impedance plots. The photocatalytic activity of PMT was performed under UV irradiation with the help of degradation kinetics of organic pollutants. Also, the photocatalytic efficiency of recycled and reused PMT finds 91.2% after 5th cyclic runs. The calculated band-gap is found to be 3.58 eV.

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Moumin Rudra, T. K. Bhowmik, H. S. Tripathi, R. A. Kumar, R. Sutradhar, T. P. Sinha. 2023-07-01. Hopping mechanisms, photoluminescence studies toward highly efficient UV-responsive Pr2MgTiO6 photocatalyst. https://doi.org/10.1016/j.physb.2021.413213

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