Superconducting Lithium Hydride in a Chemical Capacitor Setup: A Theoretical Study

Metallization of the ionic hydride LiH has never been achieved experimentally, even under high external pressure. Herein, a novel "chemical capacitor" setup to facilitate its metallization under ambient pressure conditions is applied. The findings reveal that a single layer of this material can withstand doping levels up to an impressive 0.61 holes per H atom without structural collapse, as demonstrated in the ZrC | LiH | ZrC system. Additionally, the electron-phonon coupling strength (λ) reaches a remarkable value of 2.1 in the TiO | LiH | TiO system, indicative of the strong coupling regime. Superconductivity calculations further predict a maximum critical temperature ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>T</mml:mi> <mml:mi>c</mml:mi></mml:msub> </mml:mrow> <mml:annotation>$T_{\text{c}}$</mml:annotation></mml:semantics> </mml:math> ) of 17.5 K for 0.31-hole-doped LiH with (LiBaF₃)₂ as surrounding support layers in the absence of external pressure.