Aqueous-phase reforming of organic molecules to hydrogen is a promising strategy to address the production and storage of sustainable hydrogen with lower costs; however, the synthesis of inexpensive transition metal (TM) catalysts with desirable activity and stability for the reaction is still challenging. In this work, a green and efficient approach for modulating the geometric/electronic structure of metal/hydrochar nanocomposites from sustainable biomass was proposed for enhancing H2 production via aqueous-phase reforming of methanol (APRM). A Ni/HC nanocomposite with a special thistle (a perennial species of flowering plant)-like three-dimensional (3D) architecture was first constructed as a model catalyst to expatiate the critical role of modulating an ordered mesoporous structure and interface electron transfer for enhancing APRM. Deliberately balancing heteroatom doping and soft templates contribute to the successful fabrication of the thistle-like superstructure, and such hierarchically porous architectures demonstrated efficient catalysis for APRM, owing to their unique properties, including a highly uniform morphology, narrow particle size distribution, and mesoporous texture with excellent accessibility. In addition, the experimental investigation and density functional theory calculations both substantiated that the combination of heteroatom doping and soft templates was beneficial for the strong electronic metal-support interaction (EMSI) of the metal/hydrochar nanocomposite, which leads to enhanced methanol adsorption, activation, and subsequently improved APRM performance. The electronic structure of the metal/hydrochar nanocomposite played a more significant effect on the intrinsic APRM activity than the geometric structure like the formation of the thistle-like superstructure. Benefiting from the tailored electronic and geometric structure, the resulting Ni0.1/HC-N1.5-S1 catalyst exhibited an unprecedented average turnover frequency (TOF) of 89.5 molH2/molNi/min, higher than any other known platinum group metal-free catalysts, approaching the reactivity of the state-of-the-art noble metal-based APRM catalysts, while showing excellent stability over 10 consecutive reaction cycles.
Bibliographical noteFunding Information:
The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (22108291), National Key Research and Development Program of China (No. 2019YFC1805802-04), Department of Science and Technology of Sichuan Province (No. 2018JZ0016), Open Project of State Key Laboratory of Solid Waste Reuse for Building Materials (No. SWR-2020-002), Open Project of Key Laboratory of Environmental Biotechnology, CAS (No. kf2019003), and the Youth Innovation Promotion Association CAS (Chao Gai, 2021039). This research was also supported by the Hydrogen Energy Innovation Technology Development Program of the National Research Foundation of Korea (NRF) funded by the Korean government (Ministry of Science and ICT (MSIT)) (No. NRF-2019M3E6A1064197) (Prof. Yong Sik Ok).
© 2021 American Chemical Society
- clean and affordable energy
- heteroatom doping
- hydrogen society
- hydrothermal carbonization
- metal−support interaction
- supported metal catalysts
ASJC Scopus subject areas
- Materials Science(all)