To investigate the structural, electronic, optical and magnetic properties of Sr-doped KNbO₃ for perovskite solar cell applications: A DFT study

Abstract

A First-principles study based on density functional theory was conducted to examine the different properties of pure and Sr-doped-KNbO3-perovskites materials such as structural, optical, and electronic properties. The current research was conducted by using CASTEP (Cambridge Serial Total Energy Package) code with USP (Ultra-soft Pseudo-potential) and PBE (Perdew Burke-Ernzerhof) exchange co-relational functional of GGA (Generalized Gradients Approximation). By using a generalized gradient approximation (GGA) and an ultra-soft pseudo potential. The Sr effect on structural, electronic, and optical properties of Sr-doped-KNbO3 was investigated using a generalized gradient approximation (GGA) and an ultra-soft pseudo-potential. The band gap of Sr-doped-KNbO3 was found to remarkably increased from 1.50 eV to 1.83 eV after the doping of Strontium (Sr) with various percentages (0%, 12.5%, 25%, 37.5%). Under the DFT study, strontium(Sr) is appropriate material for increasing the band gap of KNbO3. Owing to the difference in ionic radii of Mo and Sr volume of crystal cells also decreased from 82.68 to 42.89A3 after the doping of Strontium (Sr). The nature of the band gap was found indirect moreover band gap indicated that the material was a prominent semiconductor. A significant increment was found in the band gap and optical conductivity. After the substitution of strontium (Sr) impurities, the energy absorption peaks increased. It was also observed that after doping with Sr optical conductivity shifted toward larger energies because of the band gap. Sr-doped-KNbO3 has high optical conductivity, refractive index, and energy absorption making it an appropriate material for Perovskite solar cell applications.

A DFT approach to explore the structural, optoelectronic, mechanical, and thermoelectric attributes of lead-free RbInX3 (X = I, Br, Cl) halide perovskites for renewable energy applications

“…An indirect band gap of 0.9 eV is observed at (L-X) symmetry points for RbInBr 3 , as represented in figure 2(b). Upon halide substitution, it is seen that the observed bandgap is enhanced, which is influenced by the electronic states (mostly valence and conduction) of the halide anion that leads to a decrease in electron binding [71]. In addition,…”

Band Gap and Polarization Tuning of Ion-Doped XNbO3 (X = Li, K, Na, Ag) for Photovoltaic and Energy Storage Applications

“…For Au- and Ag-doped LNO, Zainuddin et al [ 15 ] calculated a smaller band gap value compared with the pure one. Using the DFT, Jameel et al [ 16 ] showed that Sr-doped KNO is an appropriate material for perovskite solar cell applications. The effect of defects on the spontaneous polarization in pure and doped LNO from first principle calculations were studied by Wang et al [ 17 ].…”

Doping Effects on the Multiferroic Properties of KNbO3 Nanoparticles

“…Therefore, it is a promising candidate for room-temperature multiferroic applications. Density functional theory, using ultra-soft pseudo-potential, was used to study the structural, electronic, magnetic, and optical properties of Sr-doped KNO by Jameel et al [11]. The authors showed that Sr-doped KNO has enhanced band gap, optical conductivity, energy absorption, and refractive index, making it an appropriate material for perovskite solar cell applications.…”

“…The majority of theoretical papers that have studied the properties of ion-doped KNO are based on density functional theory [11,13,15]. DFT is a very powerful tool for investigating many-body problems.…”