Long Used but Hardly Known: Synthesis and Crystal Structure of Tritium Breeding Li₂Be₂O₃

A main challenge for the operation of a nuclear fusion reactor is the consumption of tritium during the fusion process and the limited availability of tritium in natural resources or its production in nuclear power plants. The most promising approach is breeding of new tritium within the operating fusion reactor. For this purpose, suitable breeding materials are needed. Lithium beryllium oxides are a promising class of compounds, as they unite both target and neutron multiplier in one material. While there have already been studies on sintered ceramics in the Li₂O·BeO system, the crystal structure of compounds of a defined composition has so far remained unsolved. Herein, we report on the synthesis of phase-pure Li₂Be₂O₃ in a high-temperature (HT) approach and its structure determination by single-crystal X-ray diffraction (sc-XRD). In addition, the compound was characterized by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis. The thermal stability, which is important for use as blanket material in a fusion reactor, was examined with differential scanning calorimetry (DSC).