Spatial-confinement synthesis of single-crystal ZrCo nanoparticles for ultrafast and long-life hydrogen/hydrogen isotope storage

Abstract

ZrCo alloy is a safe and low-cost H-isotope storage material for controlled nuclear fusion, but traditional ZrCo prepared by smelting method suffer from slow gas uptake/release kinetics and serious degradation of cycle performance. Here, a “bottom-up” synthesis method is developed to prepare highly crystalline and high-purity ZrCo micron-/nanoparticles via a spatial-confinement strategy. The size-dependent hydrogen storage performances are systematically investigated from the perspectives of lattice constant, crystallinity, grain boundary, stress, and disproportionation phase transition. Compared with micron-scale polycrystalline smelted-ZrCo, the comprehensive performances of nanoscale ZrCo single crystals are significantly improved, including a 19-fold increase in kinetic rate, a ∼ 50% reduction of disproportionation ratio, and a two-fold improvement in cycle stability. This study provides a promising direction and an efficient synthetic method for the preparation of high-performance ZrCo alloys, which will facilitate their application in controlled nuclear fusion.