Exploring the physical properties of the perovskite-type hydrides NaXH3 (X = Ni, Cu, Zn) for hydrogen storage applications: A DFT study

The current global energy demands and environmental concerns have highlighted the potential of hydrogen as a crucial component of a sustainable energy strategy for the twenty-first century. This research employed first-principles computations to investigate the perovskite-type hydrides NaXH₃ (X = Ni, Cu, Zn). The structural optimizations revealed negative formation energies, indicating their thermodynamic stability and synthesizability. The mechanical stability was studied using elastic constants, while the electronic properties were examined through band structures and partial densities of states, confirming their metallic nature. Bader partial charge analysis shed light on the charge transfer characteristics, and phonon dispersion curves demonstrated their dynamic stability. Importantly, these hydrides exhibit promising hydrogen storage capacities of 3.57, 3.38, and 3.31 wt% for NaXH₃ (X = Ni, Cu, and Zn), respectively. This study represents a novel exploration of these perovskite hydrides, potentially paving the way for further advancements in hydrogen storage technologies.