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Energy efficient buildings require materials with a low thermal conductivity and a high fire resistance. Traditional organic insulation materials are limited by their poor fire resistance and inorganic insulation materials are either brittle or display a high thermal conductivity. Herein we report a mechanically resilient organic/inorganic composite aerogel with a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance. Co-polymerization and nanoscale phase separation of the phenol-formaldehyde-resin (PFR) and silica generate a binary network with domain sizes below 20 nm. The PFR/SiO₂ aerogel can resist a high-temperature flame without disintegration and prevents the temperature on the non-exposed side from increasing above the temperature critical for the collapse of reinforced concrete structures.

Fire not starter: Taking advantage of a co-polymerization strategy an organic–inorganic binary network hybrid aerogel with a nanoscale homogeneity can be prepared. The phenol-formaldehyde-resin/SiO₂ aerogel is mechanically resilient and has a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance.

It is a challenging task to realize the vision of hierarchically structured nanomaterials for large-scale applications. Herein, the biomaterial wood as a large-scale biotemplate for functionalization at multiple scales is discussed, to provide an increased property range to this renewable and CO₂-storing bioresource, which is available at low cost and in large quantities. The Progress Report reviews the emerging field of functional wood materials in view of the specific features of the structural template and novel nanotechnological approaches for the development of wood–polymer composites and wood–mineral hybrids for advanced property profiles and new functions.

Wood, as a biomaterial, can be used as a large-scale bioscaffold and template for functionalization at multiple scales in a top-down approach. This emerging research field is reviewed by discussing nanotechnological approaches for the development of wood–polymer composites and wood–mineral hybrids, as well as wood-based devices for advanced property profiles and new functions.

BiOClxI1-x solid solutions with different bandgaps were synthesized by adjusting the initial Cl to I molar ratios via chemical precipitation method at room temperature. The structures, morphologies, and optical properties of the samples were characterized by XRD, XPS, Raman, SEM, TEM, and UV-vis, respectively. The photocatalytic experiments showed that the BiOCl0.9I0.1 sample totally decomposed a large concentration of 50 mg L-1 aqueous Rhodamine B (RhB) solution within 12 minutes under the visible light irradiation (λ>420nm), which is 11 times higher than that of pure BiOI. Furthermore, the electron band structure and states density of BiOCl, BiOI and BiOClxI1-x have been investigated using the DFT (Density Functional Theory) calculation method and electrochemical method. It was found that there are some multiple crystal defects of Bi5+, Bi(3-x)+ and oxygen vacancy in the BiOClxI1-x samples. The results for Mott-Schottky plots and Valence band XPS spectra showed the position of conduction band (CB) for BiOCl0.9I0.1 was up-shift, which is favorable to the redox capacity for the photocatalysts. It could be elucidated that the synergistic effects of multiple crystal defects and unique band structure are critical to improving solar driven photocatalytic activity. This work provides a new highlight toward the construction of high property photocatalysts by tuning the crystal defect and band structure in a simple and efficient way.

Superhydrophobic surfaces repel water and, in some cases, other liquids as well. The repellency is caused by topographical features at the nano-/microscale and low surface energy. Blood is a challenging liquid to repel due to its high propensity for activation of intrinsic hemostatic mechanisms, induction of coagulation, and platelet activation upon contact with foreign surfaces. Imbalanced activation of coagulation drives thrombogenesis or formation of blood clots that can occlude the blood flow either on-site or further downstream as emboli, exposing tissues to ischemia and infarction. Blood-repellent superhydrophobic surfaces aim toward reducing the thrombogenicity of surfaces of blood-contacting devices and implants. Several mechanisms that lead to blood repellency are proposed, focusing mainly on platelet antiadhesion. Structured surfaces can: (i) reduce the effective area exposed to platelets, (ii) reduce the adhesion area available to individual platelets, (iii) cause hydrodynamic effects that reduce platelet adhesion, and (iv) reduce or alter protein adsorption in a way that is not conducive to thrombus formation. These mechanisms benefit from the superhydrophobic Cassie state, in which a thin layer of air is trapped between the solid surface and the liquid. The connections between water- and blood repellency are discussed and several recent examples of blood-repellent superhydrophobic surfaces are highlighted.

Superhydrophobic surfaces can reduce the adhesion and activation of platelets and thus show promise for blood-repellent surfaces. The micro- and nanotopographies reduce the effective area exposed to blood and provide insufficient adhesion areas for platelets. Superhydrophobic surfaces also alter protein adsorption and flow patterns. However, questions remain regarding the safety and stability in physiological conditions.

Light-responsive hydrogels show promise in targeted drug delivery, as they can load and deliver sensitive cargo when triggered. To make these hydrogels more amenable for use in vivo, I. J. Dmochowski and colleagues have used a nontoxic ruthenium-based crosslinker to form a hydrogel that degrades upon irradiation with visible light, releasing an active protein cargo. For the full story see the Communication on page 2328 ff.