Zhu Yi, Pan Hongfei, Li Qi, Huang Xiege, Xi Wei, Tang Haibo, Tu Wenmao, Wang Shihao, Tang Haolin, Zhang Haining
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China.
R&D Center of Materials and Stack Technology for Fuel Cell, National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies, Foshan Xianhu Laboratory, Foshan, 528200, China.
Adv Sci (Weinh). 2024 Nov;11(43):e2406659. doi: 10.1002/advs.202406659. Epub 2024 Sep 24.
Hydrogen production from the decomposition of ammonia is considered an effective approach for addressing challenges associated with hydrogen storage and transportation. However, their relatively high energy consumption and low efficiency hinder practical multi-scenario applications. In this study, YO-stabilized catalysts with Co-loaded onto porous nitrogen-doped carbon (YO-Co/NC) are synthesized by pyrolysis of Y(NO)-modified ZIF-67 under an inert atmosphere, followed by annealing in a reducing environment. The introduction of YO enhanced the recombination and desorption of N atoms and facilitated the gradual dehydrogenation of NH on the catalyst surface, resulting in improved catalytic activity for the thermal decomposition of ammonia. Benefitting from the electron-donating properties of YO and N-doped carbon, the optimized catalyst achieved a remarkable NH conversion efficiency of 92.3% at a high gas hourly space velocity of 20 000 cm· ·h with an encouraging H production rate of 20.6 mmol· ·min at 550 °C. Moreover, the synthesized catalyst undergoes a fast-dynamic reconstruction process, resulting in exceptionally stable catalytic activity during the thermal decomposition of ammonia, rendering it a promising candidate for carbon-free energy thermocatalytic conversion technology.
氨分解制氢被认为是应对与氢储存和运输相关挑战的有效途径。然而，它们相对较高的能耗和低效率阻碍了实际的多场景应用。在本研究中，通过在惰性气氛下热解Y(NO)改性的ZIF-67，然后在还原环境中退火，合成了负载Co的多孔氮掺杂碳（YO-Co/NC）稳定的催化剂。YO的引入增强了N原子的复合和解吸，并促进了NH在催化剂表面的逐步脱氢，从而提高了氨热分解的催化活性。受益于YO和氮掺杂碳的供电子特性，优化后的催化剂在20000 cm³·h⁻¹的高气时空速下实现了92.3%的显著NH₃转化效率，在55℃时具有令人鼓舞的20.6 mmol·g⁻¹·min⁻¹的H₂产率。此外，合成的催化剂经历了快速动态重构过程，在氨热分解过程中具有异常稳定的催化活性，使其成为无碳能源热催化转化技术的有前途的候选者。
