Fuel cell technology based on stationary and mobile applications is needing new hydrogen storage materials equipped with huge gravimetric and volumetric hydrogen densities. Examining the fundamental properties of hydrides is an important part of such process, mainly to understand the structure change's impact on the hydrogen storage. Herein, we applied ab-initio density functional theory using full potential linear augmented plane method to explore the effect of rubidium and cesium doping in sodium borohydride, NaBH₄. The electronic structure calculations exposed the semiconducting nature of NaBH₄ and derived doped structures NaRbBH₄ and NaCsBH₄. The hydrogen (H₂) storage capacity is found 10.66 wt %, 3.27 wt % and 2.36 wt % within a reasonable free energy of −28.514 kJ/mol, −29.709 kJ, −28.51 kJ/mol for NaBH₄, NaRbBH₄ and NaCsBH₄ respectively from quasi-harmonic approximation. Also, we extracted the heat capacity and Debye temperature from vibrational analysis based on phonon calculation. The discovered features show the potential use of presented sodium borohydrides for practical H₂ storage devices.

基于固定和移动应用的燃料电池技术需要配备巨大重量和体积氢密度的新型储氢材料。检查氢化物的基本特性是该过程的重要组成部分，主要是为了了解结构变化对储氢的影响。在这里，我们应用从头开始的密度泛函理论，使用全势线性增强平面方法来研究explore和铯掺杂对硼氢化钠NaBH _4的影响。电子结构计算暴露了NaBH ₄的半导体性质，并推导了掺杂结构NaRbBH ₄和NaCsBH ₄。氢（H ₂）的存储容量被发现10.66重量％，3.27重量％和2.36重量％-28.514千焦/摩尔，-29.709千焦，-28.51千焦/摩尔的合理自由能内，用于将NaBH ₄，NaRbBH ₄和NaCsBH ₄从准分别谐波近似。此外，我们基于声子计算从振动分析中提取了热容量和德拜温度。发现的特征表明所提出的硼氢化钠可用于实际的H ₂储存装置。