The production of pure hydrogen for use in energy applications and related industries often relies on the permeation of hydrogen through palladium-based membranes. However, the scarcity of Pd reserves necessitates the development of affordable alternatives with high hydrogen permeability. Here we report room-temperature hydrogen permeability of titanium nitrides (widely used as tough and inert coating materials) enabled by mixed hydride ion–electron conductivity. Combined spectroscopic, permeability and microgravimetric measurements reveal that nanocrystalline TiN _x membranes feature enhanced grain-boundary diffusion of hydride anions associated with interfacial Ti cations on nanograins. Since the corresponding activation energies are very low (<10 kJ mol^–1), these membranes yield a considerably higher room-temperature hydrogen flux than Pd membranes of equivalent thickness. Overall, the current study establishes general guidelines for developing hydride ion transport membranes based on a simple transition metal nitride for hydrogen purification, membrane reactors and other applications.

用于能源应用和相关行业的纯氢的生产通常依赖于氢通过钯基膜的渗透。但是，Pd储量的稀缺性使得必须开发出具有高氢渗透性的可负担的替代品。在这里，我们报告了混合氢化物离子-电子电导率能使氮化钛（广泛用作坚韧和惰性的涂层材料）在室温下的氢渗透性。光谱，渗透率和微重力测量的组合显示，纳米TiN _x膜的特征是与界面Ti阳离子相关的氢化物阴离子在纳米颗粒上的晶界扩散增强。由于相应的活化能非常低（<10 kJ mol ^–1 ），这些膜比同等厚度的Pd膜产生更高的室温氢通量。总体而言，当前的研究建立了开发基于氢离子净化，膜反应器和其他应用的简单过渡金属氮化物的氢化物离子迁移膜的一般指导原则。