3 Shaping of metal-organic frameworks (MOFs) has become increasingly studied over the past few 4 years because it represents a major bottleneck toward their further applications at larger scale. 5 MOF-based macroscale solids should present similar performances to their powder counterparts along with adequate mechanical resistance. 3D printing is one of the promising technologies as it 7 allows the fast prototyping of materials at the macroscale; however, the large amounts of added 8 binders have a detrimental effect on the porous properties of the solids. Herein, a 3D printer was 9 modified to prepare a variety of MOF-based solids with controlled morphology from shear-10 thinning inks containing 2-hydroxyethyl cellulose. Four benchmark MOFs were tested for this 11 purpose: HKUST-1, CPL-1, ZIF-8 and UiO-66-NH 2. All solids are mechanically stable up to 0.6 12 MPa of uniaxial compression and highly porous with BET specific surface areas lowered by 0 to 13-25%. Furthermore, these solids were applied to high pressure hydrocarbon sorption (CH 4 , C 2 H 4 14 and C 2 H 6) and presented consequent methane gravimetric uptake (UiO-66-NH 2 , ZIF-8, and 15 HKUST-1) and highly preferential adsorption of ethylene of ethane (CPL-1).

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Enormous efforts have been devoted to the development of crystalline aerogels toward heterogeneous catalysis, energy storage, ion/ molecular absorption, and luminescence. However, properties of aerogels are not fully exploited due to their low content of functional moieties embedded in their solid networks, low crystallinity, and limited chemical compositions. Herein, we develop a one-pot approach based on crystallization from amorphous metal hydroxides modified with a β-diketone ligand, toward crystalline transition-metal hydroxide aerogels. Synthesis of monolithic and crystalline aerogels of layered double hydroxide (LDH) was performed in a Ni−Al system starting from aqueous ethanol solutions of NiCl 2 •6H 2 O and AlCl 3 •6H 2 O with acetylacetone (acac) as an organic ligand. Propylene oxide (PO) as an alkalization reagent was added into precursory solutions to yield monolithic wet gels. The successive pH increase induces the formation of a threedimensional (3-D) solid framework composed of amorphous Al(OH) 3 . Then, amphoteric Al(OH) 3 undergoes crystallization into Ni−Al LDH via an acetylacetone-driven dissolution−crystallization of metal hydroxides without destroying the preformed 3-D solid framework. The process allows us to obtain crystalline aerogel monoliths with high porosity and high transparency after supercritical CO 2 drying of wet gels. The present scheme can be expected to synthesize functionalized aerogel composed of crystalline transitionmetal oxide/hydroxide nanobuilding blocks (NBBs).

We report a new synthetic strategy to realize highly transparent aerogels with outstanding bending flexibility. Taking poly(methylsilsesquioxane) (PMSQ) aerogels as an example, surfactant-induced fiber-like mesoscopic assembly of PMSQ and poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO, so-called Pluronics) has been demonstrated. The obtained PMSQ aerogels possessed a characteristic branched fibrous structure in the mesoscale. With employing various kinds of PEO-b-PPO-b-PEO as the structure determining agent, optimization of the mesoscale structure of PMSQ gels has realized highly transparent aerogels with outstanding bendability compared to those reported in previous works. This approach provides a novel way to thermally superinsulating flexible devices with glasslike transparency.

We report a new synthetic strategy to realize highly transparent aerogels with outstanding bending flexibility. Taking poly(methylsilsesquioxane) (PMSQ) aerogels as an example, surfactant-induced fiber-like mesoscopic assembly of PMSQ and poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO, so-called Pluronics) has been demonstrated. The obtained PMSQ aerogels possessed a characteristic branched fibrous structure in the mesoscale. With employing various kinds of PEO-b-PPO-b-PEO as the structure determining agent, optimization of the mesoscale structure of PMSQ gels has realized highly transparent aerogels with outstanding bendability compared to those reported in previous works. This approach provides a novel way to thermally superinsulating flexible devices with glasslike transparency.