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A visible-light-induced decarboxylation reaction was developed for the synthesis of alkylated benzimidazo[2,1-a]isoquinoline-6(5H)-ones and indolo[2,1-a]isoquinolin-6(5H)-ones under metal-free conditions. Impressively, metal catalysts and traditionally volatile organic solvents could be effectively avoided.

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 (HPPD, EC 1.13.11.27) is an important target site for discovering new bleaching herbicides. To explore novel HPPD inhibitors with excellent herbicidal activity, a series of novel N-aroyl diketone/triketone derivatives were rationally designed by splicing active groups and bioisosterism. Bioassays revealed that most of these derivatives displayed preferable herbicidal activity against Echinochloa crus-galli (EC) at 0.045 mmol/m2 and Abutilon juncea (AJ) at 0.090 mmol/m2. In particular, compound I-f was more potent compared to the commercialized compound mesotrione. Molecular docking indicated that the corresponding active molecules of target compounds and mesotrione shared similar interplay with surrounding residues, which led to a perfect interaction with the active site of Arabidopsis thaliana HPPD.

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.

A simple one-step solvothermal route was developed to fabricate homogenous cesium tungsten bronze (Cs0.32WO3) nanoparticles, and an environmentally friendly aqueous solution was used to prepare transparent NIR shielding coatings. Based on the results, the addition of Cs+ ions promoted the formation of Cs2WOCl5 crystals, which inhibited the hydrolysis process of WCl6 and limited the formation of hexagonal tunnels. Controlled formation of hexagonal tunnels is favorable for Cs+ ions that completely enter the hexagonal vacant tunnels to form the Cs0.32WO3 crystals. Via a controllable formation process, the superior crystalline Cs0.32WO3 nanoparticles with the primary particle size of 30–60 nm were synthesized at the low temperature of 200 °C and short time of 4 h without any other additives. Furthermore, the Cs0.32WO3 nanoparticles were well dispersed in the aqueous solution, and the as-prepared coating exhibited a high SETS value (0.72), which remained constant with an increase in the film thickness. Simulated solar irradiation experiments revealed that the as-prepared film cut off over about 91.6% of radiation. The simulated model of the real environment revealed that compared with the ordinary glass and commercial Cs0.32WO3, the as-prepared Cs0.32WO3 film showed superior NIR shielding performance for practical application.

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.

Heteroatom-doped carbon nanotubes (CNTs) have great potential in various fields owing to their extraordinary electronic, structural, and mechanical properties. However, large-scale production of heteroatom-doped CNTs in a simple, economical, and highly efficient manner still remains challenging. Here, we report a modified Pechini method (MPM) for high-yield synthesis of N- and O-codoped CNTs (N,O-CNTs), by rapid pyrolysis of a NiCo-polymer precursor forming via a simple sol-gel process. The carbon source (i.e., citric acid) is inexpensive, and the NiCo-polymer material is the single precursor for the preparation of N,O-CNTs via a thermolysis process without the introduction of additional catalysts or carrier gas. Appropriate NiCo-organic coordination and controlled pyrolysis (i.e. heating rate, pyrolysis temperature, and holding time) are demonstrated to play vital roles in this MPM, which are critical for quick generation of small NiCo nanocatalysts with high catalytic activity and simultaneous formation of sufficient space inside the material. The growth mechanism is well studied. Benefitting from the hierarchically porous structure and the synergistic effect of N,O-codoping in the CNTs, the as-synthesized N,O-CNTs manifest excellent electrochemical performance in both supercapacitors and electrocatalysis. Density functional theory simulations show that N and O dopants could increase the densities of states of CNTs near the Fermi level and charge densities of adjacent C atoms, thus leading to improved electrochemical activity. We anticipate that this work will open up a new avenue for a high-yield and economical synthesis of heteroatom-doped CNTs for energy-related applications and beyond.

A concise one-pot three-component thioamination of 1,4-naphthoquinone with thiols and amines was developed to synthesize 2-amino-3-thio-1,4-naphthoquinones. The approach employed CuI as the catalyst and ambient O2 as the green oxidant, giving a series of thioaminated 1,4-naphthoquinones in moderate to good yields. This catalytic approach represents a step-economic and convenient strategy for the difunctionalization of 1,4-naphthoquinones.

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.

Paraffin wax (PW) is widely used for smart thermoregulation materials due to its good thermal performance. However, the leakage and low thermal conductivity of PW hinder its application in the heat storage field. Accordingly, developing effective methods to address these issues is of great importance. In this study, we explored a facile approach to obtain PW-loaded core-sheath structured flexible nanofibers films via coaxial electrospinning technique. The PW as the core layer was successfully encapsulated by the sheath-layer poly(methyl methacrylate). The diameter of the fiber core increased from 395 to 848 nm as the core solution speed rate increased from 0.1 to 0.5 mL/h. In addition, it can be seen that higher core solution speed rate could lead to higher PW encapsulation efficiency according to the transmission electron microscopy results. The core-sheath nanofiber films, moreover, possessed the highest latent heat of 58.25 J/g and solidifying enthalpy of -56.49 J/g. In addition, we found that after 200 thermal cycles, there was little change in latent heat, which demonstrated that it is beneficial for the PW-loaded core-sheath structure to overcome the leakage issue and enhance thermal stability properties for the thermoregulation film.

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.

In this review article, Mn applications have been divided into three parts. We provide an overview of recent progress in developing Mn4+ doped red phosphors for promising application in warm white light-emitting diodes. In addition, we summarize reports on Mn2+ co-doped Eu2+ or Ce3+ phosphors that can produce white light with outstanding color rendering index (CRI) and color coordinates via energy transfer processes, and report the application of Mn2+ in green to NIR phosphors.

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.

A nickel-catalyzed, efficient C-N bond reduction of aromatic and benzylic ammonium triflates has been developed using sodium isopropoxide as a reducing agent. The high efficiency, mild conditions, and good compatibility with various substituents made this method an effective supplement to the current catalytic hydrogenation reactions. Combining this reductive deamination reaction with directed aromatic functionalization reactions, a powerful strategy for regioselective functionalization of arenes was demonstrated using dialkylamine groups as traceless directing groups.

A piezoelectric semiconducting ZnO nanowire under the action of a torque is analyzed. The shear stresses in the cross-section are acquired from classical elasticity. Based on the obtained results, the electric potential, the electric field and the electric displacements can be found from the Gauss law in electrostatics together with the conservation of charge. Numerical results show that the torque deformation produces large effect on the electric displacements but little contribution to the electric potential. The study is helpful to development of piezoelectric semiconductor devices.

2D nanomaterials are well suited for energy conversion and storage because of their thickness-dependent physical and chemical properties. However, current synthetic methods for translating 2D materials from the laboratory to industry cannot integrate both advantages of liquid-phase method (i.e., solution processibility, homogeneity, and massive production), and gas-phase method (i.e., high quality and large lateral size). Here, inspired by Chinese Sugar Figure Blowing Art, a rapid "gel-blowing" strategy is proposed for the mass production of 2D nonlayered nanosheets by thermally expanding the viscous gel precursors within a short time (≈1 min). A wide variety of 2D nanosheets including oxides, carbon, oxides/carbon and metal/carbon composites are synthesized on a large scale and with no impurities. Importantly, this method unifies the merits of both liquid-phase and gas-phase syntheses, giving rise to 2D products with high uniformity, nanometer thickness, and large lateral sizes (up to hundreds of micrometers) simultaneously. The success of this strategy highly relies on the speed of "blowing" and control of the amount of reactants. The as-synthesized nanosheet electrodes manifest excellent electrochemical performance for alkali-ion batteries and electrocatalysis. This method opens up a new avenue for economical and massive preparation of good-quality nonlayered 2D nanosheets for energy-related applications and beyond. Ministry of Education (MOE)