Effect of strontium substitution on the physical properties of BaLiH 3 : A first-principles investigation

Hydride perovskites are promising candidates for next-generation functional materials due to their interesting properties. Our calculations confirm that all studied compositions satisfy the different stability criteria. Ba[Formula: see text]Sr x LiH 3 has a wide band gap that can be tuned by Sr doping. Optical calculations highlight strong absorption in the ultraviolet region, supporting potential applications in UV filtering and protective coatings. In the visible region, the studied compounds are characterized as promising candidates for anti-reflecting coating and thin lens fabrication. Ba[Formula: see text]Sr x LiH 3 possesses a high Seebeck coefficient and ZT value approaching unity, particularly at [Formula: see text], making it suitable for energy harvesting and thermal management devices. This study paves the way for the use of Ba[Formula: see text]Sr x LiH 3 in high-frequency electronics, optoelectronics and thermoelectric applications. Temperature-dependent hydrogen storage calculations show that hydrogen remains trapped for a much longer time in barium-rich compounds, often lasting several days at room temperature, but it is released much more rapidly as the strontium content increases.