We report the preparation of hexagonal mesoporous silica from single-source giant surfactants constructed via dihydroxyl-functionlized polyhedral oligomeric silsesquioxane (DPOSS) heads and a polystyrene (PS) tail. After thermal annealing, the obtained well-ordered hexagonal hybrid was pyrolyzed to afford well-ordered mesoporous silica. A high porosity (e.g., 581 m 2 /g) and a uniform and narrow pore size distribution (e.g., 3.3 nm) were achieved. Mesoporous silica in diverse shapes and morphologies were achieved by processing the precursor. When the PS tail length was increased, the pore size expanded accordingly. Moreover, such pyrolyzed, ordered mesoporous silica can help to increase both efficiency and stability of nanocatalysts.

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N-doped carbon materials represent a type of metal-free catalyst for diverse organic synthetic reactions. However, single N-doped carbon materials perform insufficiently in the selective oxidation reaction of C−H bond compared with metal catalysts or multielement co-doped materials. There are a few reports on the application of three-dimensional (3D) carbon materials in such a reaction. Besides, the relationship between the well-developed porous structures, heteroatom doping, and their catalytic performance is unclear. In this study, 3D porous N-doped graphene aerogel catalysts with high activity and selectivity for the C−H bond oxidation under mild reaction conditions have been synthesized through a two-step method. Systematic studies on the dosage of N sources, pyrolysis temperature, and their influences on the catalytic performances have been evolved. Moreover, solid evidence of the synergistic effect of sp 2 C atoms adjacent to the N atoms and porous structure promoting the performance has been provided in this work.

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Although liquid-phase catalytic exchange is an environmentally friendly treatment of hydrogen isotopes in recycled water of a nuclear power station, the successive development of hydrophobic catalysts is still needed to meet much higher catalytic exchange efficiency and stability. Herein, a dual-modified graphene with Pt loading was designed by amination and silanization to anchor Pt nanoparticles uniformly, as well as obtain higher hydrophobicity. After coating the reactor walls with poly­(dimethylsiloxane), the catalytic exchange efficiency of the dual-modified graphene with lower Pt loadings (Pt/200-S-NH2-GR) improved up to 91% at 80 °C, which was higher than 80% of only animated graphene (Pt/NH2-GR) at the same condition. Furthermore, the Pt/200-S-NH2-GR maintained high stability for at least 10 h in the temperature range of 40–80 °C, while the Pt/NH2-GR decreased 17% of catalytic exchange efficiency at 80 °C within 10 h. Using the dual-modified strategy for graphene support, high efficiency and stability was achieved for heavy water dedeuteration.

Liquid phase catalytic exchange of hydrogen isotopes is intensified by stratified flow in a microchannel reactor coated with hydrophobic Pt/AC/PDMS.

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