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A series of Pt/CeO 2 compounds with hollow spheres (Pt/CeO 2 –S), wires (Pt/CeO 2 –W), and particle (Pt/CeO 2 –P) morphologies were prepared and further used for catalytic liquid organic hydrogen carrier (LOHC) dehydrogenation. The exposure and distribution of different crystal faces affected the nucleation process of crystals and then formed different microscopic morphologies. Compared with Pt/CeO 2 –W and Pt/CeO 2 –P, Pt/CeO 2 –S showed hollow spherical structures with significantly higher oxygen vacancy concentrations and specific surface areas. These structural differences not only affected platinum (Pt) dispersion, but also affected the activity and stability of the catalyst, thus promoting methylcyclohexane (MCH) conversion. The fixed bed reaction showed that Pt/CeO 2 –S had excellent catalytic activity, with the MCH conversion rate at 97.7 % and hydrogen release rate of 350.50 mmol/g (Pt) /min, and it still maintained stable activity after 72 h. Under the same conditions, the MCH conversion rates for Pt/CeO 2 –W and Pt/CeO 2 –P were only 77.23 % and 32.02 %, respectively. Therefore, through the growth pattern and morphology controls of catalyst supports, this was an effective means for improving the dehydrogenation performance of LOHC. • The growth mechanism of CeO 2 hollow spheres, wires, and particles. • High catalytic activity of Pt/CeO 2 hollow spheres. • Liquid organic hydrogen carrier dehydrogenation. [ABSTRACT FROM AUTHOR]

Herein, to efficiently improve the lithium storage of Fe 3 O 4 nanoparticles, a distinctive porous carbon (PC) assisted carbon nanotubes (CNTs) supporting architecture has been designed and fabricated successfully. The Fe 3 O 4 nanoparticles are deposited on the surface of CNTs and then covered by an extra PC. In such a designed architecture, highly conductive and robust CNTs can not only improve the conductivity but also boost the structure of the as-fabricated Fe 3 O 4 -based composite (CNTs@Fe 3 O 4 @PC). In particular, the foam-like PC has a certain level of volume elasticity and open tunnel-like structure to better anchor the Fe 3 O 4 nanoparticles on the surface of CNTs and facilitate the transfer of electrons and ions, therefore guaranteeing the fast kinetics and long-term stability. The results show that the capacitive contribution is predominant in lithium storage of the CNTs@Fe 3 O 4 @PC electrode. Consequently, the as-fabricated CNTs@Fe 3 O 4 @PC shows high capacity, good rate capability, and long life, displaying 766 and 572 mAh g-1 after 400 and 700 cycles at 200 and even 1000 mA g-1, respectively. Thus outstanding performance makes the CNTs@Fe 3 O 4 @PC have great potential to be advanced lithium-ion battery anode materials. Furthermore, this strategy can be extended to other nanostructured metal oxide anodes, such as CoO, SnO 2 , and Bi 2 O 3 nanomaterials. [ABSTRACT FROM AUTHOR]