Catalytic synergy of BaTiO3/carbon nanotubes in LiBH4: in-situ formation of active species for enhanced hydrogen storage performance

The practical application of LiBH 4 for solid-state hydrogen storage is hindered by its sluggish kinetics and high thermodynamic stability. To address these challenges, we constructed a multiphase catalytic system within LiBH 4 by incorporating nano-BaTiO 3 and carbon nanotubes (CNTs) through ball milling. The composite of LiBH 4 , 20 wt% BaTiO 3 and 20 wt% CNTs exhibits significantly enhanced dehydrogenation properties, with an initial temperature as low as 223 °C and a peak desorption temperature of 353 °C, releasing 8.2 wt% H 2 at 500 °C. The modified composite demonstrates markedly improved reversibility and kinetics, evidenced by a retained capacity of 4.1 wt% after the 6th cycle and a substantially decreased activation energy of 123 kJ mol −1 . During the first dehydrogenation, LiBH 4 reacts in-situ with BaTiO 3 to form Li 3 BO 3 , BaB 6 , and TiO 2 phases. These products, in conjunction with CNTs, form a multifunctional catalytic framework. Among them, BaB 6 serves as the nucleation site, TiO 2 acts as the active catalyst, and Li 3 BO 3 facilitates ion transport, collectively enhancing the reaction kinetics and cycling stability of LiBH 4 . Meanwhile, the CNTs provides dual functions of confinement and excellent thermal conductivity, which suppressing particle aggregation and enhancing thermal diffusion rate. Consequently, the composite exhibits a lower decomposing temperature, rapider kinetics, and enhances reversibility compared with the as-milled LiBH 4 . This work provides an effective strategy of in-situ engineering a multiphase interface to attain high-performance solid-state hydrogen storage materials.