Cation-dependent hydrogen vacancy stability in XNH 4 (X = Li, Na, K): thermodynamic crossover, chemical potential, and implications for hydrogen release
In this theoretical study, we employ first-principles density functional theory calculations using the generalized gradient approximation to systematically investigate the structural, electronic, and thermodynamic properties of alkali–ammonium compounds XNH 4 (X = Li, Na, K) intended for solid-state hydrogen storag...