中科院大连化物所陈平团队报道了用于超离子传导的变形三氢化镧。相关研究成果于2023年4月5日发表于国际一流学术期刊《自然》。

氢化物离子（H^-）具有强还原性和高氧化还原电位，是一种活性氢物种和能量载体。在环境条件下传导纯H的材料将成为先进清洁能源存储和电化学转换技术的推动者。然而，以H快速迁移而闻名的稀土三氢化物也表现出有害的电子导电性。

该文中，研究表明，通过在晶格中产生纳米尺寸的晶粒和缺陷，LaH_x的电子导电性可以被抑制五个数量级以上。这将LaH_x在-40°C下转化为超离子导体，具有创纪录的1.0×10^-2Scm^-1的高H^-电导率和0.12eV的低扩散势垒。并展示了室温全固态氢化物电池。

附：英文原文

Title: Deforming lanthanum trihydride for superionic conduction

Author: Zhang, Weijin, Cui, Jirong, Wang, Shangshang, Cao, Hujun, Wu, Anan, Xia, Yuanhua, Jiang, Qike, Guo, Jianping, He, Teng, Chen, Ping

Issue&Volume: 2023-04-05

Abstract: With strong reducibility and high redox potential, the hydride ion (H) is a reactive hydrogen species and an energy carrier. Materials that conduct pure H at ambient conditions will be enablers of advanced clean energy storage and electrochemical conversion technologies1,2. However, rare earth trihydrides, known for fast H migration, also exhibit detrimental electronic conductivity3,4,5. Here we show that by creating nanosized grains and defects in the lattice, the electronic conductivity of LaHx can be suppressed by more than five orders of magnitude. This transforms LaHx to a superionic conductor at 40°C with a record high H conductivity of 1.0×102Scm1 and a low diffusion barrier of 0.12eV. A room-temperature all-solid-state hydride cell is demonstrated.

DOI: 10.1038/s41586-023-05815-0

Source: https://www.nature.com/articles/s41586-023-05815-0