Two-dimensional C@TiO2/Ti3C2 composite with superior catalytic performance for NaAlH4. (21st August 2020)

• Record Type: Journal Article
• Authors: Yuan, Zhenluo; Fan, Yanping; Chen, Yumei; Liu, Xianyun; Liu, Baozhong; Han, Shumin
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 41(2020)
• Page Start: 21666
• Page End: 21675
• Publication Date: 2020-08-21
• Subjects: Hydrogen storage materials -- Sodium alanate -- Dehydrogenation kinetics -- Two-dimensional materials -- Catalytic activity; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.05.243
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Carbon coated titanium dioxide supported on two-dimensional titanium carbide (C@TiO2 /Ti3 C2 ) is synthesized by simple annealing under a flowing acetylene (C2 H2 ) atmosphere, and applied to improve the hydriding/dehydriding behavior of sodium alanate (NaAlH4 ). The results indicate that as-prepared C@TiO2 /Ti3 C2 composite exhibits excellent catalytic activity. The initial temperature for hydrogen desorption is reduced by 70 °C compared with the pristine sample. About 4.0 wt% hydrogen is released in 13 min at 140 °C. The apparent activation energies ( E a ) of 10 wt% C@TiO2 /Ti3 C2 catalyzing NaAlH4 for the first two-steps dehydrogenation are 72.41 and 64.27 kJ mol −1 respectively. The structural analyses reveal that C@TiO2 /Ti3 C2 interacts with NaAlH4 by using ball milling and decomposes to form Ti-species which works in combination with carbon to improve the dehydrogenation performance of NaAlH4 . This result provides an important progress in the hydrogen storage of NaAlH4 catalyzed by MXene. Highlights: 2D C@TiO2 /Ti3 C2 is synthesized by annealing Ti3 C2 MXene under C2 H2 atmosphere. C@TiO2 /Ti3 C2 exhibits superior catalytic activity for hydrogen storage in NaAlH4 . Remarkable improvement in dehydrogenation kinetics and cycling stability of NaAlH4 . Ti-species and carbon contributes to the improved dehydrogenation properties.