Department of Materials Science and Engineering, University of Rajshahi, Bangladesh

Title of the Invited Talk: Structures, Properties, Applications, and Challenges of Perovskites and Advanced Materials in Research Collaboration Spots

Abstract: Perovskites are treated as one of the most promising classes of exciting materials because of their distinctive crystal symmetry, physio-chemical, biological attributes and applications in the superconducting, magnetic, dielectric, piezo/ferroelectric, multiferroic, magneto-electric/tronic, electronic, optoelectronics, thermoelectric, photovoltaic, photocatalytic, thermoelectric, and spintronic fields. In my research collaboration, mainly Bi/Nb/Ti base novel compositional perovskite oxides whose different elements occupy A and/or B sites in ordered ways are synthesized by facile ecofriendly low temperature hydrothermal/solvothermal route from 180 to 250 °C. The structure of the powder samples has been investigated using laboratory X-ray diffraction, high-resolution synchrotron-XRD (SXRD), powder neutron diffraction (NPD), and electron diffraction (SAED) patterns using TEM analysis. The refinement based on SXRD and NPD data using chemical analysis results determined their crystal structure precisely, and established structure property relationship in the synthesized perovskites. Morphology, micro/nano structures and elemental compositional homogeneity on the nanoscale were verified by scanning electron microscopy and TEM images, respectively. The hydrothermally synthesized novel commotional perovskites exhibited a large shielding volume fraction with the highest onset of superconductivity up to ~31.5 K, and zero resistivity was achieved at 13 K. The fabricated compounds underwent thermal decomposition above 400 °C with superconductivity. Local structure and elemental compositions have been determined by FTIR/Raman and EDS/XPS data, respectively. Moreover, optical responses, antimicrobial activity, piezoelectric constant (d33), and magnetic behaviors of synthesized structural materials are studied to explore their prominent characteristics. In the theoretical studies DFT (density functional theory) based first principles computations are employed to study the structural, mechanical, electronic (DOS/Band, Fermi surface, charge density), optical, thermodynamic, thermoelectric, and superconducting properties of these new perovskite superconductors and relevant structures. Recently, combined DFT methods and SCAPS-1D simulation software are also utilized to study the photovoltaic (PV) performance of perovskite and other solar cells (PSCs) by optimizing the optoelectronic parameters of the absorber, electron transport layer (ETL), hole transport layer (HTL), and various interface layers.