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A metal-free photocatalytic oxidative decarboxylation reaction at room temperature was developed for the synthesis of aromatic aldehydes and ketones from the corresponding arylacetic acids. The reaction was realized under blue-light irradiation by adding 1 mol% of 4CzIPN as photocatalyst and air as oxidant. This reaction represents a novel decarboxylation of a sp3-hybridized carboxylic acids without traditional heating, additional oxidants, and metal reagents under mild conditions.

4-Hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27, HPPD) is a very important target for the discovery of novel bleaching herbicides. In order to discover novel triketone green HPPD inhibitors with excellent herbicidal activity and crop selectivity, the natural product leptospermone was selected as the template compound, and niacin was employed as bioisostere to design and synthesize a series of novel substituted niacin-triketone derivatives. Some of the target compounds showed potent Arabidopsis thaliana HPPD (AtHPPD) inhibitory activity in vitro. Especially compound II-1 displayed the best herbicidal activity (IC50 = 0.262 μM, AtHPPD), and was safe for Zea mays at concentration of 300 g ai/ha. Molecular docking results indicated that the triketone moiety of compound II-1 could form a bidentate complex with Fe(II), and the pyridine subunit interacted with Phe430 and Phe360 via π−π packing. The present work indicated that 3-hydroxy-2-nicotinoylcyclohex-2-en-1-one could be a potential lead structure for developing novel green HPPD inhibitors.

The VO2/Cs0.32WO3 composite thermochromic films were designed to promote the practical application of the VO2-based smart windows. The addition of 0.9 wt% Cs0.32WO3 can significantly shorten the phase transition response time and improve the solar heat shielding capacity of VO2, while maintaining high visible light transmittance (49.6%) and good solar modulation ability (10.4%). Furthermore, the phase transition of the composite film can occur at indoor temperature of 30 °C, and the indoor temperature can be greatly reduced by 7.7 °C under the simulated solar irradiation. These excellent properties make the VO2/Cs0.32WO3 films promising as smart energy-saving windows.

In this work, the V2O3 nanoparticles (NPs) with ultrathin carbon shells were synthesized by a facile solvothermal process. The V2O3 NPs were about 30 nm and contained a carbon shell of about 2 nm thick. The V2O3 NPs were homogeneously dispersed and loosely packed. When used as anode material, the V2O3 core-shell NPs showed a reversible capacity up to 525 mA h g−1 at 200 mA g−1 over 200 cycles with good cycle stability and rate capability. The excellent electrochemical performance promotes its practical application in lithium-ion batteries.

The development of rational material structure design for thermo-regulated smart textiles based on phase change materials (PCMs) paraffin wax (PW) is paramount for effectively solving leakage issue in the process of phase change. Here, a material structure with high-performance in overcoming leakage of PW is achieved by coaxial electrospinning technique resulting from core-sheath structured smart textiles with PW as core layer and polyacrylonitrile (PAN) as sheath layer. Additionally, to improve the heat utilization efficiency of solar energy, the hexagonal cesium tungsten bronze (Cs0.32WO3) with excellent near-infrared region (NIR) absorbing ability is incorporated in the textiles. It is noteworthy that the smart textile possesses the high encapsulation efficiency of 54.3% (latent heat of 60.31 J/g) and shows good stability because of almost no change of latent heat for the smart textiles after 500 heating-cooling cycles. Hence, this work provides a meaningful guidance for smart textiles and opens up some opportunities for comfortable wearing.

Inspired by the phase change materials (PCMs) based microcapsules, green phase change nanofibers mats with core-sheath structure based on paraffin wax emulsion (PWE) and polyvinyl alcohol (PVA) for thermal energy storage (TES) is obtained by coaxial electrospinning approach. The PWE could be encapsulated by PVA, simultaneously addressing the leakage issue effectively. In addition, the melting enthalpy (ΔHm) increased from 3.16 J/g to 48.35 J/g as the core speed rate (Rcore) increased from 0.1 to 2.0 μl/min, indicating higher Rcore can induce higher PWE encapsulation efficiency. Finally, the core-sheath structure PWE@PVA nanofibers mats have high ΔHm of 48.25 J/g and freezing enthalpy (ΔHc) of -47.75 J/g. Furthermore, only slightly decreasing tendency on the enthalpy can be observed after 500 heating-cooling cycles, demonstrating good TES stability and practicability of the as-prepared PWE@PVA nanofibers mats. Hence, this study offers new idea for the fabrication method of green PCMs.

In this work, the recyclable nanofibers membrane with good adsorption performance based on molybdenum disulfide (MoS2) was obtained via combination of simple hydrothermal and electrospinning approach. The membrane exhibited superhydrophilic property which was beneficial for water treatment. In addition, the maximum adsorption capacity of the MoS2-loaded nanofibers membrane for rhodmine B (RhB) was 77.70 mg/g, and it exhibited excellent desorption property in acetone due to the decrease of solvent polarity. More importantly, the removal efficiency was kept at 97.7% after thirty cycles of adsorption/desorption process, indicating its good reutilization. Furthermore, the adsorption behavior of the MoS2-loaded nanofibers membrane can be well described by the Langmuir isotherm model and pseudo-second-order kinetic model. The high adsorption capacity and recyclability render the PAN-MoS2 nanofibers membrane good performance in practicability for removal of organic dye.

In this work, we report for the first time the applications of cationic oligomeric surfactants as novel air entraining agents for concrete. A series of oligomeric surfactants with the oligomerization degrees from 2 to 4 was synthesized. Using them as the air entraining agents, the surface activity and foaming properies were tested in both water and cement filtrate. The air contents and air-void parameters were also tested in both cement mortars and concretes. The results show that the oligomeric surfactants have higher performance compared with their monomeric analogue and traditional air entraining agents, and the surfactant with higher oligomerization degree has higher performance. The surfactants are also beneficial for the durability of concrete, and could only affect the strength of concrete slightly. Our studies indicate great potential of the oligomeric surfactants for practical applications.

This work developed novel transparent nanocomposite film with thermochromic and hydrophobic properties fabricated by electrospinning and hot-pressing approach. The homogeneous composite nanofibers mats were obtained via co-electrospinning the organic polymer polymethylmethacrylate (PMMA) and inorganic VO 2 (M) nanoparticles. The VO 2 (M) nanoparticles with average diameter of 30 nm were distributed in the electrospun nanofibers and isolated from air simultaneously, which was beneficial for antioxidation of the VO 2 (M). Additionally, the mechanical property of the nanocomposite films with different stacked layers was always improved significantly via hot-pressing treatment. Moreover, the thermochromic property of the film showed the solar modulation ability Δ T sol of 7.31% and the luminous transmittance of 29.6% at 550 nm. Thus, the study offered a new notion for the energy-saving material, and it could be a good promising substitute of smart glass.

Eu 3+ -doped M BaY 1-x Eu x (BO 3 ) 2 ( M = Na, K) red emitting nanophosphor was prepared via a sol-gel method. The phase purity and crystal structure of the nanophosphors were confirmed by X-ray diffraction (XRD) together with the Rietveld refinements. The surface morphology was characterized by scanning electron microscope (SEM). The luminescent characteristics of the particles were investigated by photoluminescence emission (PL) and excitation (PLE) spectra, decay curves and quantum efficiencies (QE). The phosphors present a very high optimal doping concentration of about 70 mol%. The phosphor presents the dominated 5 D 0 → 7 F 1 transition inducing reddish-orange color in lower doping, while it has a red emission at 613 nm from the electronic 5 D 0 → 7 F 2 dipole transition in a Eu 3+ -heavily doped sample. The thermal stabilities of the two phosphors were tested by measuring their temperature-dependent emission intensities. The luminescence differences between the Na- and K-compounds were presented and discussed base on the structure characteristics.

The development of high performance air entraining agents for concrete is of great importance. In this work, sulfonic gemini surfactants have been utilized as high performance air entraining agents for the first time. Six sulfonic gemini surfactants with different hydrophobic chains and spacer groups were designed and synthesized. The surface tensions and foam properties of their aqueous solutions were tested. Using them as the air entraining agents, the air contents and air-void parameters of the cement mortars were also tested. The properties of different geminis and their single-chained analogue were fully compared and discussed. The results show that the geminis have higher surface activity, foamability, foam stability and air entraining performance compared with their single-chained analogue, and the gemini with 12-carbon hydrophobic chains and 2-carbon alkyl spacer has highest performance.

Adsorbents including CuCl2-AC, CuCl2-13X, Cu(NO3)2-AC and Cu(NO3)2-13X were prepared to remove trace phosphine from recycled hydrogen in the Siemens process of producing polysilicon, and adsorptive mechanisms were determined by X-ray diffraction and intermittent breakthrough experiments. CuCl2 could disperse better on supporters than Cu(NO3)2, and it existed in its original form. However, Cu(NO3)2 decomposed into copper oxide or basic cupric nitrate, and showed conspicuous thermal aggregation effect after calcination. Interactive effects between cupric components and supporters varied form species to species and deactivated the reactivity of CuCl2 and Cu(NO3)2 in different degree, which resulted in disparities of adsorbents’ performances. CuCl2-AC and Cu(NO3)2-AC had better performances than CuCl2-13X and Cu(NO3)2-13X because cupric components were deactivated more when loaded on 13X zeolite. Chemical transformation of phosphine made adsorbents’ surface renewable, and the renewed rate depended on the reactivity of cupric components. All of adsorbents showed significant recoveries of efficiencies in intermittent experiments.

Main-chain/side-chain combined liquid crystalline polymers (MCSCLCPs) are usually difficult to synthesize and their degrees of polymerization are relatively low, which bring difficulties in studying their structure–property relationships. In order to solve this problem, we prepared a new series of MCSCLCPs containing mesogen-jacketed liquid crystalline polymer (MJLCP) main chains via hydrogen-bonding (H–B). A pyridine derivative with a triphenylene (Tp) unit is the H–B acceptor. In addition to the temperature dependence, the phase behavior of the resulting complex is strongly influenced by the content of the H–B acceptor and the rigidity of the side-chain core of the MJLCP. The resulting complexes exhibit different phase structures: (1) a columnar nematic phase or a smectic A (SmA) phase formed by the supramolecular MJLCP chain as a whole; (2) hierarchical nanostructures including a hexagonal columnar phase or a SmA phase of the whole polymer chain plus a discotic nematic phase associated with the Tp moieties.