Metals/metal hydrides have attracted much attention for hydrogen storage and sensing owing to their excellent ability to store hydrogen. The nanomodification strategy has a remarkable effect on the improvement of hydrogen storage and sensing properties. Herein, the nanomodification strategy mainly includes nanoconfinement for metal hydrides, nanosized metals/metal hydrides, and nanoadditives for metal hydrides. We first review the properties of metal hydrides and summarize the research process of nanosized metal hydrides and nanoadditives for metal hydrides in the recent five years. The synthesis methods of preparing nanometal hydrides are outlined, which includes the bottom-up and top-bottom strategy. Notably, the effort of the nanoconfinement, which limits the growth and the aggregation of metal hydride particles, is presented with detailed introduction of many different kinds of host materials, including carbons, metal-organic frameworks, porous metals, porous metal oxides, and so on. The effect on the enhanced hydrogen storage performance by nanosized metal hydrides is emphasized. In addition, we sum up the research studies about various kinds of nanoadditive doping into metal hydride systems, such as metals and intermetallic compounds, metal oxides and sulfides, metal fluorides, and so on. We study and highlight the influence of metal hydrides doped with nanoadditives with improved kinetics for hydrogen storage. Besides, we also investigate the hydrogen sensing property of nanostructured noble metals, as well as the process of metal hydride formation. Future research directions and perspectives are also being discussed for the development of hydrogen storage and sensing based on metals/metal hydrides.

金属/金属氢化物由于其出色的储氢能力而备受氢和传感技术的关注。纳米改性策略对改善储氢和传感性能具有显著作用。在此，纳米改性策略主要包括用于金属氢化物的纳米限制，用于纳米金属/金属氢化物的纳米尺寸以及用于金属氢化物的纳米添加剂。我们首先回顾一下金属氢化物的性质，并总结了近五年来纳米级金属氢化物和用于金属氢化物的纳米添加剂的研究过程。概述了制备纳米金属氢化物的合成方法，包括自下而上和自上而下的策略。值得注意的是，纳米限制的努力限制了金属氢化物颗粒的生长和聚集，介绍了许多不同种类的主体材料，包括碳，金属有机骨架，多孔金属，多孔金属氧化物等。强调了对纳米金属氢化物增强的储氢性能的影响。此外，我们总结了对金属氢化物体系中各种纳米添加剂的研究，如金属和金属间化合物，金属氧化物和硫化物，金属氟化物等。我们研究并强调了掺杂有纳米添加剂的金属氢化物对氢存储动力学的影响。此外，我们还研究了纳米结构贵金属的氢感测特性以及金属氢化物的形成过程。