Selectively exposing active surfaces of Pt-based nanoframes (NFs) can promote electrocatalysis of small organic molecules, especially regarding improved diffusion and anti-poisoning properties. However, the systematic investigation on the synthesis, as well as structure-property relationship, of Pt-based NFs with tunable external and internal surface structures is still at its early stage. Herein, we report a facile, environmental and one-pot approach to fabricate PtCuNi NFs with tunable external and internal surface structures by flexibly adjusting coordination and reducing agents. Interestingly, electrocatalytic results reveal that the PtCuNi NFs with variable external structures possess higher performance (activity and anti-CO-poisoning capability) than those with tunable internal structures as well as commercial Pt/C. Especially, the PtCuNi eb-NFs (external branch NFs) exhibit the excellent specific activities of methanol and formic acid electrooxidation reactions (MOR and FAOR), 10.7 and 7.9 times higher than those of commercial Pt/C, respectively. The PtCuNi eb-NFs also possess a superior diffusion ability for methanol electrooxidation (0.0276) and formic acid electrooxidation (0.0153) compared to other PtCuNi NFs with plentiful internal surface. The enhanced MOR and FAOR activities of PtCuNi eb-NFs are ascribed to its abundant external surface area and high defect-density (e.g. vacancy, subtle lattice distortion and high-index facets), which results in an optimal anti-CO-poisoning capability due to the diffusion and ligand effects. This work opens up a new pathway for enhancing the electrooxidation properties (anti-poisoning property and diffusion rate) of liquid fuels by tuning the surface structures of nanoframe catalysts.

The pore structure and acid sites of the catalysts are demonstrated as the main factors for the hydro-upgrading of fluid catalytic cracking (FCC) gasoline. Herein, we report a general synthesis of ZSM-5/SBA-15 composite zeolites with tunable pore structure and acid sites. The effects of the pore structure and acid sites of these catalysts on their hydro-upgrading performance were systematically investigated. The platelet CoMo/AZS-PL (CoMo/ZS-PL-γ-Al2O3) catalyst with the short mesochannels, appropriate Co–Mo–S phase, and suitable acidity exhibited the excellent preservation ability of research octane number (RON) and hydrodesulfurization (HDS) performance, which was better than those of CoMo/AZS-SR (CoMo/ZS-SR-γ-Al2O3), CoMo/AZS-HP (CoMo/ZS-HP-γ-Al2O3), and CoMo/AZS-LR (CoMo/ZS-LR-γ-Al2O3) catalysts. The relationship between the physicochemical properties (acidity, morphology, pore structure, and sulfided active metal) of the catalysts and their isomerization (ISO), aromatization (ARO), as well as HDS abilities were explored in detail.

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