No abstract

Employing DFT technique, we perform Pt/Ni doping and Pt-Ni co-doping into CeO2. We study the structural, electronic, magnetic, and optical properties of CeO2 with selected dopants using Wien2k code. Spin-polarized DOS illustrate non-magnetic character of pure CeO2 while Pt/Ni/Pt-Ni doping yields magnetism into CeO2 with magnetic moment values of 2.2502 μ_B, 2.5683 μ_B, and 3.9190 μ_B, respectively. Active participation of Ce 4f-, Pt 4d- and Ni 3d-states at the Fermi level suggests remarkable improvement in the conduction process. p-d hybridization is observed and it produces good response in electronic properties. Pt@CeO2 and Pt-Ni@CeO2 exhibit blueshift while Ni@CeO2 exhibit redshift in absorption spectrum. We notice an enhancement in optical absorption and conductivity with decreased reflectivity of these proposed materials in the UV region. Tuning of absorption spectra and decrease in band gap of these materials indicate their uses for photocatalytic, photonic, optoelectronics and power electronic devices. 

Search of new novel materials for bringing advancement in the field of energy storage and optical materials is tremendously growing in order to meet future challenges. Gallium nitride (GaN) shows exceptional optoelectronic behavior which is highly needed for production of optoelectronic devices. Therefore, in this research study, we investigate the structural, electronic, magnetic, and optical properties of zirconium doped GaN (Zr@GaN) and Ti-Zr co-doped GaN using the Wien2k code. Proactive role of dopants Ti and Zr d-states is observed which appreciably tune electronic properties. GaN remains non-magnetic after zirconium substitution with Ga atom however, Ti-Zr co-doping produce magnetism into GaN with total magnetic moment of 1.503 . Absorption spectrum of Zr@GaN shows blueshift while for Ti-Zr@GaN material exhibit redshift. However, absorption spectra of both proposed materials significantly enhanced in the UV region which propose their potential uses in the high power UV optoelectronics, spintronics, photonics, and photovoltaic devices.