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A series of fluorine-silicon block urethane acrylates (PSi-FMPG-IPDI-HEMA) were synthesized from hydroxypropyl-terminated polysiloxane (PSi), newly-prepared fluorodiol (FMPG), isophorone diisocyanate (IPDI) and hydroxyethyl methacrylate (HEMA). Their molecular structures were characterized by Fourier transform infrared and gel permeation chromatography. The compatibility of the oligomers with HFMA was validated using UV–vis transmittance analysis. The thermal stability, water and chemical resistance, contact angles and anti-adhesive performance of the films were measured. It was found all the films had good thermal properties, and excellent water and chemical resistance. The FMPG content affected the surface energy and anti-adhesive performance of the films. The films with more FMPG presented lower surface energy, lower peel strength, and higher residual adhesion. More importantly, the release films designed based on the fluorine-silicon block urethane acrylates had tremendous application potential.

Herein, a novel strategy was proposed for the fabrication of hierarchical porous silica materials templated by a poly ionic liquid (PIL, a copolymer of 1-butyl-3-vinylimidazolium bromide and acrylamide) and P123 (PEO20PPO70PEO20). The PIL acts as a co-solvent as well as a co-template in the system. The effects of the concentration of the PIL and pH on the morphology and structure of silica materials were systematically investigated. Hierarchical porous silica materials were characterized by X-ray diffraction, N2 adsorption–desorption, transmission electron microscopy and Fourier transform infrared (FTIR) spectroscopy. Moreover, the results demonstrated that the porous silica materials were equipped with a dual-mesoporous channel structure and possessed a high surface area and large pore volumes up to 1274 m2 g−1 and 1.41 cm3 g−1, respectively. Furthermore, a high-performance catalyst-based supported ionic liquid phase (SILP) was obtained by surface modification with the IL (1-(tri-ethoxy-silyl-propyl)-3-methylimidazolium chloride) of the carrier and anion exchange with HPW. Catalytic performances were investigated in the alkylation of styrene with o-xylene. Moreover, it was found that the as-synthesized catalysts showed high catalytic performance in terms of styrene conversion and selectivity to 1-phenyl-1-xylyl ethane (PXE). Specifically, the catalyst PIL-1.0g-2-IL-HPW showed excellent activities in both the yield (91.5%) and selectivity (96.8%) for this alkylation reaction.

Hollow microtubule structured nano-/micromaterials of hollow tubular g-C3N4 (TCN) enwrapped with nanosheets were fabricated by a three-step method. By calcining NiCo-layered-double-hydroxides/tubular-cyanuric acid-melamine (NiCo-LDH/TCM) precursor prepared through using 2-methylimidazole as precipitant and methanol as solvent, the as-prepared NiCo-alloy@tubular-g-C3N4 (NC@TCN) shown excellent microwave absorption in the frequency range of 2–18 GHz. The optimal reflection loss (RL) of −35.63 dB was observed at 5.00 GHz and an effective absorption bandwidth of 4.80 GHz at a matching layer thickness of 2.0 mm. Our results indicated that the deposition of NiCo-alloy nanoparticles on g-C3N4 microtubule was an efficient way to fabricate g-C3N4-based high-performance microwave absorbers.

Metal-organic framework (MOF)-derived porous metal/C composites have drawn considerable attention from the microwave absorption field owing to their large pore volumes and surface areas. Exploring single-MOF-derived materials with high intensity and broadband absorption is largely needed but remains a challenge. Here, porous Co/ZnO/C (CZC) microrods were fabricated easily from cuboid-shaped heterobimetallic MOFs. CZC provides an efficient platform for integrating different semiconductors (ZnO), magnetic metal (Co), and carbon sources into one particle, which enhances the electromagnetic (EM) wave-absorbing ability. The carbonization temperature which is critical for EM parameters was studied in detail. CZC annealed at 700 °C outperformed those obtained at 600 or 800 °C in terms of microwave wave-absorbing properties. The reflection loss (RL) was optimized to -52.6 (or -20.6) dB at 12.1 (or 14.8) GHz with an effective bandwidth (RL ≤ -10 dB) of 4.9 (or 5.8) GHz at the coating thickness of 3.0 (or 2.5) mm. Such enhancement of EM wave-absorbing capabilities is ascribed to the well-built porous structure, dielectric loss, and magnetic loss. This work offers a new way to prepare porous magnetic metal/C composites with excellent microwave-absorbing properties starting from heterobimetallic MOFs.

Flower-like P-doped graphitic carbon nitride (g-C3N4) with a high surface area and porosity has been prepared via a facile, template-free, cost-effective and thermal copolymerization route, using phosphoric acid as the phosphorus source and a cyanuric acid–melamine complex as the supramolecular precursor. It could be found that phosphoric acid could stabilize the three-dimensional character of the as-prepared P-doped g-C3N4 and the g-C3N4 micro-flower consisted of ultrathin nanosheets which possessed abundant mesopores. The unique structure, combined with phosphorus heteroatom doping, promoted the utilization of visible light and improved the separation and mobility of photogenerated charges. The obtained P-doped g-C3N4 exhibited prominent photocatalytic performance in the water splitting for the hydrogen evolution reaction under visible light irradiation. The hydrogen evolution rate reached 256.4 μmol h−1, almost 24 times higher than that of pristine g-C3N4. Meanwhile, a possible mechanism for photocatalytic hydrogen evolution was proposed according to the results.

Passively responsive thermochromic smart window, which can modulate indoor incident solar light automatically at relatively high outdoor temperature, is a practical energy-saving device for construction and automotive industries. In this paper, a thermochromic composite hydrogel film based on W-doped vanadium dioxide (W-VO2), poly N-isopropyl acrylamide (PNIPAM) and polyacrylamide (PAM) is presented and this hydrogel film was prepared between two quartz substrates to form the sandwich structured smart window. In this thermochromic system, 2 wt% monoclinic W-VO2 were dispersed in the hydrogel film with the thickness of 0.1 mm. The introduction of PAM changes the flow-state PNIPAM microgel to hydrogel, which dramatically improved the practicality of the PNIPAM-based smart window. When the outdoor temperature is higher than 40 °C, the solar modulation capacity of this passive smart window, with a high luminous transmittance of 72% at 25 °C, can reach 46.3%. The smart window possesses high solar modulation ability and more than 20% luminous transmittance even after 40 times high temperature durability tests.