Tuning of band gap and enhancing electronic properties of CsSnBr3 under high pressure for optoelectronic applications

Abstract

Recently, inorganometallic halide perovskite semiconductors have emerged as promising candidate for novel industrial demands like optoelectronic devices and photovoltaic (PV) solar cells. Herein, the essential properties of CsSnBr3 have been calculated through the first principles DFT. CsSnBr3 shows stable cubic structure (Pm-3m) at all pressures accompany by ductile nature and strong resistance to shear deformation. Pressure clearly affects the M-M direct band-gap, Eg = 0.979 eV (P = 0 GPa), 0.334 eV (P = 10 GPa), 0.271 eV (P = 20 GPa), 0.078 eV (P = 30 GPa), and 0.0 eV (P = 40 GPa). We found that the nonmagnetic semiconductor CsSnBr3 shows high absorption in the visible spectrum at all pressures. The responses disclose that optical parameters increase and drag towards high energies with an increase of pressure. The narrow band-gap and high absorption have made CsSnBr3 suitable material for electronics, optoelectronics and photovoltaics applications. The thermoelectric response reveals that the conduction is through electrons (n-type) and perfect (ZT = 1.0) at high temperature and pressure, which unveil the potential of CsSnBr3 for thermoelectric devices. The current results would be beneficial and can provide a gateway to how the physical properties of CsSnBr3 could be tuned by applying pressure.