Full-inorganic metal halide perovskites ATX3 as promising candidate materials for future photovoltaics and optospintronics applications

A number of compounds belonging to the full-inorganic metal halide perovskite family with the general chemical formula (ATX3) have been widely investigated over the past two decades. This huge interest is aimed not only at researching the charming physical and chemical characteristics of ATX3, such as flexible crystal structure, tunable semiconducting bandgap (Eg < 2.5 eV), high charge-carrier mobility, a large optical absorption coefficient αω, and high composition stability, but also at seeking promising and multifunctional thermal, electrical, and optical applications that give an extraordinary power-conversion efficiency (PCE) of more than 24.0% in photovoltaic (PV) solar cell technology. The current challenge is to synthesize ATX3 materials that provide unique and suitable properties, including notable chemical stability at high temperatures, high electrical PCE, broad emission, and tunable semiconducting Eg. Motivated by the A+, T2+, and X− substitution effect on the main physical properties of ATX3, we extended this concept to produce a new series of cubic (Pm-3m) metal halide perovskites with (A+ = Rb+, Ce+), (T2+ = Ge2+, Sn2+), and (X− = Cl−, Br−, I−) sites and to examine their crystal structure, stability, and electronic and optical characteristics in detail. Besides that, all raw inorganic materials that can be used in producing ATX3 are cost-effective, abundant in nature, and non-toxic at high temperatures. This research identifies the favorable characteristics of ATX3 materials that selectively make them highly promising candidates for future technologies of highly efficient PV solar cells and for other probable applications in photosensors, photodetectors, LEDs, and other optospintronic applications.