Extended Data Fig. 1: Composition and structural properties of the as-prepared samples.
From: A room temperature rechargeable all-solid-state hydride ion battery
a, Hydrogen contents of the samples. *The hydrogen contents were determined by acidolysis of MHx using a hydrochloric acid solution. b, XRD patterns of the as-prepared BaH2 and CeH3. Black ticks, CeH3; red ticks, BaH2. c, XRD patterns of the nCeH3-BaH2 (n = 2, 3, 4, 5) samples. A certain amount (50% (V/V)) of silicon powder was added into the samples as an internal standard to accurately identify the phases of the mixtures. The main phase of all the nCeH3-BaH2 samples is the cubic CeH3 \(({Fm}\overline{3}m)\). The phase of BaH2 is not obvious even in the samples with higher BaH2 contents. d, XRD patterns of the 3CeH3-BaH2 samples ball milled for different time. As the milling time increases, the BaH2 phase weakens and disappears, while the crystalline phase of CeH3 retains. e, Diffuse reflectance infrared Fourier transform (DRIFT) spectra of BaH2, CeH3 and 3CeH3-BaH2 samples. The vibration bands centred at 1170 and 915 cm−1 are corresponding to Ce-H bonds and the bands centred at 1075 and 775 cm−1 belong to BaH2. After ball milling, the signals of BaH2 preserve. Noted that DRIFT is a surface sensitive technique. Although the molar ratio of BaH2 accounts only for 1/4 of the sample, the signal of Ba-H is relatively strong, indicating that BaH2 could be enriched on the surface of the material.
