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Metal–organic frameworks (MOFs) with integrated light responsiveness are highly desirable for advanced applications including sensors, gas storage and separation, and controlled delivery. Here, we ...

Macroporous NaP zeolite monoliths (M-ZPMs) with designed shapes such as cylinder, rectangular-prism, and donut shapes were synthesized via gelcasting of the aged zeolite gel with colloidal silica as a binder and subsequent vapor-phase-transport (VPT) synthesis. X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, and nitrogen gas adsorption were used to characterize the samples at different synthesis stages. SEM images revealed that the resulting macroporous NaP zeolite monoliths were composed of interconnected hollow particles. Mercury porosimetry showed that the macroporous NaP zeolite monoliths possessed bimodal macropore size distributions involving the textural macropores (ca. 100 μm) and skeletal macropores (ca. 3.5 μm). Furthermore, colloidal silica played a crucial role in the formation of robust macroporous NaP zeolite monoliths. Specifically, as the mass loading of colloidal silica in the zeolite-gel monoliths increases, the mechanical strength and Si/Al ratio of the...

A facile dual-templating approach is demonstrated to prepare hierarchically ordered macro-/mesoporous carbons. Monodispersed silica colloidal crystals are used as a hard template, amphiphilic triblock copolymer PEO−PPO−PEO as a soft template, and soluble resols as a carbon source. The procedure involves packing and aging of silica microspheres, evaporation-induced organic−organic assembly of mesostructures in the void of microspheres, thermosetting and carbonization of phenolic formaldehyde (PF), and removal of silica scaffolds by HF. The obtained porous carbons have a highly ordered face-centered cubic macrostructure with tunable pore sizes of 230−430 nm and interconnected windows with a size of 30−65 nm. The rigid silica hard templates can prevent the shrinkage of the mesostructure during the thermosetting and carbonization process, resulting in large cell parameters (∼18 nm) and pore sizes (∼11 nm). The bimodal porous carbon materials have large BET surface areas (up to 760 m2/g), large pore volumes (∼...

A mesoporous carbon structure was template-synthesized from small nanoparticles of silica with internal M41S type mesopores. The silica template was synthesized according to Suzuki et al. using an ionic surfactant to create the internal mesopores 1.8−3.5 nm diameter and a nonionic surfactant to limit the overall size of the particle. Larger mesopores in the silica are needed for carbonization to a better structure. This was achieved by the use of a swelling agent, trimethylbenzene (TMB). Characterization by transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen sorption analysis showed a mesocellular foamlike carbon structure composed of porous cells with internal hexagonally arranged channels. In addition to the 3 nm internal channels, there were larger mesopores connecting the cellular domains. These larger mesopores were formed in the interparticle voids created during carbonization. The dual porosity network structure had a high surface area (>1000 m2/g) and large pore volume (>...

With the aid of tetrapropylammonium hydroxide molecules trapped in the silicalite nanocrystals, the silicalite undergoes the structural transformation into dispersible hydroxy-sodalite nanocrystals without substantial change in morphology and size. This approach provides a new insight into zeolite crystallization and transformation and represents a facile method for synthesis of sodalite nanocrystals.