Search

In recent times, double perovskites have demonstrated promising potential as an alternative to address the instability and toxicity challenges associated with lead halide perovskites in optoelectronic applications. In this study, we successfully prepared Cs2MSbBr6 (M = Cu, Ag) double perovskite materials using the slow evaporation solution growth technique. The X-ray diffraction pattern confirmed the presence of the cubic phase in these synthesized materials. Furthermore, the optical analysis of Cs2CuSbBr6 and Cs2AgSbBr6 revealed their respective indirect bandgap energies to be 1.72 and 2.0 eV. The impedance spectroscopy technique was employed to investigate the properties of these materials, specifically double perovskites, across a frequency range of 10−1 to 106 Hz and at temperatures ranging from 303 to 403 K. To describe the AC conductivity, Jonscher's power law was utilized. The findings of the charge transportation study on Cs2MSbBr6 (M = Cu, Ag) indicate the existence of the non-overlapping small polaron tunneling mechanism in Cs2CuSbBr6, while the overlapping large polaron tunneling mechanism is observed in Cs2AgSbBr6. [ABSTRACT FROM AUTHOR]

The use of solid-state electrolytes (SSEs) instead of liquid organic electrolytes presents one of the important means to increase the energy density and resolve the protection issues of lithium batteries. The development of SSEs compounds, which can suit high-voltage cathodes and lithium metal anode (LMA) is rather important to progress high-energy–density lithium batteries. Among the different compounds, lithium aluminum titanium phosphates (LATP) are especially potential candidates for all-solid-state batteries (ASSBs) since their present high ionic conductivity, superior air stability, and low cost. In this paper, the Li1+xAlxTi2−x(PO4)3 (LATP) compounds with different mixtures have been synthesized via solid-state technique. The rhombohedral phase (space group R 3 ¯ c ) of these samples is confirmed through the powder X-ray diffraction measurements. The thermogravimetric (TG) measurements show that when x-content increments in LATP, the integral temperature of decomposition reduces. Likewise, the temperature whereupon the samples turn stable decreases, which suggested that phase stability is related by the rise of the x-content in the basic sample. Through the 101–106 Hz frequency area, the real and imaginary parts of the dielectric permittivity, the electric modulus, and alternating current (AC) conductivity of LATP samples display temperature reliance. The different contributions of grains and grain boundaries to the total impedance are confirmed by the Nyquist curves. The alternating current (AC) conductivity is illustrated in terms of Jonncher's power law. The studies on charge transportation suggest the presence of the overlapping large polaron tunneling mechanism (LATP − x = 0.0) and the non-overlapping small polaron tunneling mechanism (LATP − x = 0.3 and LATP − x = 0.5). [ABSTRACT FROM AUTHOR]