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The self-assembling nanotoxin T22-PE24 that specifically targets CXCR4 was designed to selectively deliver the cytotoxic toxin PE24 to treat CXCR4+ melanoma via activating caspase 3/GSDME pathways in which initially “cold” tumors will become “hot”.

A unique integrated cathode of Co/CeO2–NCNA@CC, which displays high power density and superior cycling stability has been constructed for Zn–air battery applications.

Hydroxyl-terminated telechelic polyisobutylene (PIB) was prepared through living cationic polymerization. A living PIB chain was formed using the t-Bu-m-DiCuOMe/TiCl4 initiating system and then capped with 1,3-butadiene (BD) to prepare chlorine-terminated telechelic PIB. The chlorine-terminated telechelic PIB was then hydrolysed with tetrabutylammonium hydroxide to form hydroxyl-terminated PIB. Nuclear magnetic resonance spectroscopy confirmed hydrolysis completion. The hydroxyl-terminated PIB was subsequently used as a diol to react with 4,4-methylenebis(phenylisocyanate) (MDI) and produce a PIB-based polyurethane, which showed stronger acid resistance, hydrolysis stability and thermal oxidation stability than a commercial polyurethane.

The cationic polymerization of isobutylene (IB) was systematically studied in a 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF6]) ionic liquid at −10 °C. Different initiating systems, including titanium tetrachloride, boron trichloride, and ethylaluminum sesquichloride, were considered in [Bmim][PF6] for IB polymerization. The effects of solvent polarity and anion/cation structure on the initiating systems and carbocation active center were simulated by density functional theory in combination with a conductor-like screening model. A highly reactive polyisobutylene (HR PIB) with a high exo-olefin end group content (>80%) was synthesized by using a H2O/TiCl4 initiating system in the [Bmim][PF6] ionic liquid. The polymerization proceeded at the interface of ionic liquid particles in a mild exothermic manner and [PF6]− anions promoted the ionization of the initiating system and stabilized the carbocation active center. A possible mechanism for HR PIB synthesis was proposed and the microstructures of ionic liquids were considered.

A self-assembling peptide nanofiber was developed to sense the microenvironmental pH change associated with bacterial growth. Using a near-infrared probe, a strong correlation was observed between the local pH reduction of bacterial colonies with the degree of peptide disassembly, which led to their enhanced antimicrobial activity against anaerobic bacteria.

Very thin silver nanowires are ideal building blocks for fabricating high-performance transparent conductive films simultaneously with low sheet resistance, high visible light transparency, a small haze factor, and high uniformity. Synthesis of very thin silver nanowires with an average diameter close to 20 nm has been realized by a polyol reduction method in the presence of Br− and Cl− ions. However, nanoparticles contained in the product are detrimental to the overall performance of transparent conductive films, and there have been no methods to purify very thin silver nanowires which are both cost-effective and environmentally friendly. In this work, we report on the Ostwald ripening-driven coarsening of the nanoparticles, followed by sedimentation and brief filtration to separate the particles from very thin silver nanowires. This method is free from the involvement of toxic acetone and could produce very thin silver nanowires with high purity. It is convenient and suitable for large-scale implementation. The films prepared with the purified very thin silver nanowires exhibit a low sheet resistance of 71.3 ± 2.9 Ω □−1 at a high transmittance of 91.7%, a low haze of 1.0%, and a small standard deviation of the sheet resistance of 4.0%, without further treatment processes. The findings in this work will pave the way for the real-world application of very thin silver nanowires towards high-performance transparent conductive films and flexible electronics.

Silver nanowire transparent conductive films are one of the most promising alternatives to indium tin oxide films in the application of touch panels. Low haze and high uniformity are two essential factors for high-end applications of the films. However, the reported haze and uniformity of such kinds of films are still lagging much behind what is required for real-world applications. Herein, the fabrication of silver nanowire transparent conductive films with an ultra-low haze and ultra-high uniformity is reported. DLVO theory is applied to purify silver nanowires and the corresponding ink of the nanowires with narrower size dispersion and less nanoparticle contaminants is formulated for film coating. The fabricated films exhibit a low haze of 0.8% and good uniformity with the non-uniformity factor of 5.0% (defined as the standard deviation of the sheet resistance) at a transmittance of 91.7% (99.4% for the silver nanowire network only without a substrate) and a sheet resistance of 71.2 Ω square−1. The outperforming films are utilized to construct touch-panels with excellent performance for fluent writing. The findings in this work will pave the way for real-world applications of silver nanowire transparent conductive films replacing those of indium tin oxide.

Designed core–shell structured titanium dioxide–poly(dopamine)-silver (TiO2–PDA-Ag) particles were prepared via self-polymerization of poly(dopamine) and electroless plating of nano-silver particles. The poly(dopamine) layer was used not only to improve the interfacial interaction between TiO2 and the nitrile-butadiene rubber (NBR) matrix but also as chemisorption sites for silver ions. Then the TiO2–PDA-Ag particles were introduced into the NBR matrix to prepare dielectric composites. The effect of the nano-Ag content on morphology, dielectric properties, and electrical properties of the composites was thoroughly investigated. It was found that the Coulomb-blockade effect of nano-Ag particles led to the composites with relatively low dielectric loss and relatively high electrical breakdown strength. This simple and effective approach provides a promising route to adjust the dielectric properties of dielectric composites via the Coulomb-blockade effect.

The synthesis of very thin Ag nanowires in the presence of Br− ions is typically accompanied by the generation of a huge amount of Ag nanoparticles. Herein, we report a method to suppress the homogeneous nucleation of Ag seeds in the growth process of Ag nanowires, hence dramatically enhancing the purity of the synthesized very thin Ag nanowires. These Ag nanowires having a diameter approaching 20 nm and an aspect ratio larger than 1500, as well as an ultra-low particle impurity level of 5.5% are directly used after simple water washing to form transparent conductive films with much improved optical and electrical properties, which have great potential for high-end applications including touch panels.

Silver nanowire transparent conductive films have been proposed as a promising candidate to replace indium tin oxide films for electronic applications. Stable ink with a high loading amount of silver nanowires is essential for the scale-up of the production of transparent conductive films considering the storage need due to separated procedures of nanowire synthesis and film formation. It is very hard to re-disperse the nanowires if irreversible aggregation happens during storage for coating. The paradox of stabilizing the concentrated nanowire ink and facile utilizing of the ink for highly conductive films with a low junction resistance at the joint points of organic stabilizer-capped silver nanowires has to be solved. A two-step method has been provided to overcome the difficulty in this work. First, a silver nanowire ink with the loading amount of 5 mg mL−1 is formulated, which is stable for more than three months under normal conditions. The success in maintaining the long-term stability lies in applying an appropriate amount of surfactant and choosing organic solvents with appropriate mixing ratios to strengthen the interaction of the surfactant with the silver nanowires and to decrease the free energy through enthalpy of mixing silver nanowires into the solvent for aggregation prevention. Second, the concentrated ink at any time is simply washed a suitable number of times and diluted to a uniform dispersion for coating of TCFs with excellent optical and electrical performance, having a figure of merit σDC/σOP (ratio of the electrical conductance to optical conductance) as high as 228. The viability of treating silver nanowires in large quantity paves the way for real industrial applications.

There has recently been a wide range of trends in the use of ionic liquids (ILs) as reaction solvent for various polymerization processes. A series of cationic polymerizations of styrene in 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF6]) had been achieved using a variety of coinitiators combined with a,a-dimethylbenzyl chloride (CumCl) as a initiator at −15 °C. Experiments were carried out to observe the influence of solvent polarity and viscosity on polymerization rate. Compared with those in organic solvents, the cationic polymerization of styrene in [Bmim][PF6] proceeded in a milder exothermic manner. The end-group structures of the polystyrenes were identified by 1H NMR spectroscopy and MALDI-TOF-MS. The corresponding elementary reactions and mechanism of styrene cationic polymerization in [Bmim][PF6] were also discussed.

In order to obtain a nitrile-butadiene rubber (NBR) dielectric elastomer composite with excellent electromechanical properties, a combination of bio-inspired poly(dopamine) (PDA) deposition and γ-methacryloxypropyl trimethoxy silane (KH570) grafting was proposed to functionalize the surface of titanium dioxide (TiO2) nanoparticles. Inspired by adhesive proteins in mussels, dopamine self-polymerization was used to deposit a thin adherent PDA film onto the surface of TiO2. KH570 that contains double bonds was then grafted through the reactions with hydroxyl and indole groups of the PDA surface. The chemical structure and composition of the TiO2 surface were characterized by XPS, FTIR, and HR-TEM. Because of the introduction of PDA grafted with the KH570 layer, the NBR composites filled with modified TiO2 displayed better filler dispersion, higher dielectric constant, lower elastic modulus, and higher electric breakdown field compared with composites filled with pristine TiO2 particles. Finally, a large actuated strain of about 16% at 60 kV mm−1 without any pre-strains was shown by the composite of NBR filled with 20 phr modified TiO2 particles, which is 53% larger than that of NBR without a filler. The process was fast, simple, efficient, nontoxic, and controllable, which can provide a new universal method for modification of dielectric fillers to improve the dielectric properties and electromechanical properties of dielectric elastomers.

In this study, a combination of bio-inspired poly(dopamine) (PDA) deposition and γ-methacryloxypropyl trimethoxy silane (KH570) grafting is proposed to functionalize the surface of barium titanate (BT) with the aim to improve the electromechanical properties of silicone dielectric elastomers. Inspired by the composition of adhesive proteins in mussels, we used dopamine self-polymerization to form a thin adherent PDA film onto the surface of BT. KH570, which contains double bonds, was then grafted through reactions with the hydroxyl and indole groups of the PDA surface. The surface composition and microstructure of the modified BT particles were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, high resolution transmission electron microscopy (HR-TEM), and thermogravimetric analysis (TGA). The results show that PDA grafted with KH570 (denoted as PDA + KH570) was successfully coated on the BT particles. In addition, the PDA + KH570 layer containing double bonds not only improved the dispersion of the fillers in the polymer matrix but also helped in the formation of strong interfacial interactions between the BT particles and silicone elastomer matrix, which led to an improved dielectric constant and actuated strain. Finally, the tensile strength of all the silicone dielectric composites is larger than 5 MPa, which is much higher than commercial acrylic dielectric elastomers. This is a big advantage for the practical application of a dielectric elastomer.

Cationic polymerization of p-methylstyrene (p-MeSt) in imidazolium-based [NTf2−1] ionic liquids (ILs) was investigated. The effects of the anions, cations, and alkyl chain length of ILs on p-MeSt solubility and viscosity were comprehensively studied. The COSMO-RS method, which is a valuable tool for screening and selecting ILs, was also applied to identify the most suitable solvent for p-MeSt cationic polymerization. The results revealed that p-MeSt cationic polymerization proceeded in a milder exothermic manner in ILs than in a traditional organic solvent. Controlled polymerizations were achieved in [Bmim][NTf2] with a CumOH/BF3OEt2 initiating system at −25 °C when 2,6-di-tert-butylpyridine was introduced. The cationic polymerization mechanism of p-MeSt in ILs was proposed on the basis of the results of density functional theory and the terminal structures of polymers.

Porous elastic and pressure-sensitive conductive polyurethane (PU) monoliths were synthesized by concentrated emulsion templating. A toluene solution containing tolylene diisocyanat (TDI), castor oil, and a surfactant was used as the continuous phase of the concentrated emulsion, and deionized water was used as the dispersed phase. In order to make the monolith conductive, acid-treated multi-walled carbon nanotubes (MWCNTs) were introduced into it, which were distributed in both phases spontaneously. After the continuous phase of the concentrated emulsion was cured, toluene and water were removed, and a highly porous elastic monolith was obtained. The MWCNTs in the continuous phase were embedded in the bulk PU matrix forming a conductive network and those previously in the dispersed phase were precipitated on the surface of the pore walls. It was the contact extent of the MWCNTs on the pore walls that rendered the monolith with pressure-sensitive conductivity. A compression strain of about 40% could cause a reduction in resistance by two orders of magnitude.

Dielectric elastomers (DEs), which are capable of displaying considerable stress and strain in response to an applied electric field, have shown the closest similarity in performance to natural muscles. However, the high operating voltage of DEs limits their practical application. A reduction of the operating voltage can be achieved through increasing the dielectric constant and/or decreasing the elastic modulus. Here, an all-organic non-percolative dielectric composite with enhanced electromechanical actuating performance was prepared by introducing polyaniline (PANI) and epoxidized soybean oil (ESO) into a nitrile-butadiene rubber (NBR) matrix. A small amount of PANI was used to increase the dielectric constant through adding electron movement which is similar to dipole polarization, while ESO was used to decrease the elastic modulus of the composite through weakening intermolecular interactions in NBR and molecular interaction between NBR and PANI. Finally, an actuated strain of 2.5% was obtained at 4.5 V μm−1 by 4 phr PANI/NBR composite filled with 50 phr ESO, a 700% improvement in actuated strain compared with the actuated strain (0.31%) of pure NBR at 4.5 V μm−1 without any pre-strains. In comparison with other dielectric composites filled with conductive filler, the ESO/PANI/NBR composite also displays a relative advantage under conditions of no pre-strain and low electric field.

Perovskite solar cells have been widely investigated owing to their high efficiency and low production cost. The working principle of perovskite solar cells is also a hot research topic. Investigations show that either the microporous oxide layer or the hole transport material could be omitted (planar configuration vs. hole-transport-material-free configuration). However, it is not known if the configuration of perovskite solar cells could be further simplified. In this work, we report on a simple hole-transport-material-free planar heterojunction perovskite solar cell with the structure FTO/hole blocking layer (compact TiO2 film)/CH3NH3PbI3/Au. We achieved a power conversion efficiency of 10.04% under one sun illumination for this simple configuration of perovskite solar cells using high-quality planar CH3NH3PbI3 films grown by a well reproducible method. Capacitance–voltage measurements show that a built-in field aiding in taking out the photocurrent to the external circuit and suppressing the back reaction of electrons from the TiO2 to the CH3NH3PbI3 film was formed in the TiO2/CH3NH3PbI3 interface depletion region. Impedance spectroscopy measurements show that a transport resistance Rtr originating from the perovskite active layer was suppressed by a large number of photo-generated currents produced at the CH3NH3PbI3 layer under light illumination.

In order to improve compatibility between the dielectric filler and polymeric matrix, we used bio-inspired polydopamine (PDA) to modify titanium dioxide (TiO2) nano-particles. The PDA coated TiO2 (TiO2-PDA) nano-particles were incorporated into nitrile-butadiene rubber (NBR) which contains a large amount polar groups to obtain a dielectric elastomer composite with a large actuated strain under a low electric field. The relatively soft insulating PDA layer on the TiO2 nano-particles led to the composites filled with TiO2-PDA nano-particles displaying better filler dispersion, much lower elastic modulus, lower dielectric loss, and higher electric breakdown field compared with the composites filled with pristine TiO2 nano-particles, resulting in a high electromechanical sensitivity (β). At last, an actuated strain of 5.2% at a relatively safe electric field of 12.5 kV mm−1 without any pre-strains was obtained by the 10 phr TiO2-PDA/NBR composite, a 140% increase in actuated strain compared with the actuated strain (0.69%) of pure NBR at 20 kV mm−1 without any pre-strains. This biomimetic method is simple, efficient, nontoxic, and easy to control, which can be used in other dielectric fillers to improve electromechanical properties of dielectric elastomers.

Cationic polymerization of isobutyl vinyl ether (IBVE) in an ionic liquid 1-octyl-3-methylimidazolium tetrafluoroborate ([omim][BF4]) was thoroughly examined at 0 °C. A variety of coinitiators were used in conjunction with the IBVE-HCl adduct acting as a cationogen. Compared with polymerization in organic solvents, the cationic polymerization of IBVE in [omim][BF4] proceeded in a milder exothermic manner, yielding polymers with higher molecular weight, and giving a higher monomer conversion. Although the polymerization reaction in [omim][BF4] could not be controlled due to the presence of β-proton elimination, the monomer addition experiments confirmed the existence of long-lived species. Introducing a small amount of 2,6-di-tert-butylpyridine (DTBP) into the system may lead to a controlled polymerization. The corresponding elementary reactions and stabilization mechanism of propagating the carbocation in [omim][BF4] were also proposed.

A simple and rapid fabrication method involving laser printing technology and in situ anodic electropolymerization is introduced to fabricate interdigital Au/polyaniline network hybrid electrodes on polyethylene terephthalate films for flexible, in-plane, and all-solid-state micro-supercapacitors. The as-obtained micro-supercapacitors acquire a maximum energy density of 5.83 mW h cm−3 and a maximum power density of 0.45 W cm−3 that are both comparable to or superior to the values obtained for currently available state-of-the-art planar supercapacitors/micro-supercapacitors. In addition, the micro-supercapacitors exhibit remarkably high mechanical flexibility and show a good cycling stability, with 72.7% retention of the specific capacity after 1000 cycles. Moreover, the micro-supercapacitors can be optionally connected in series or in parallel to meet the voltage and capacity requirements for a given application. Compared to traditional fabrication approaches for flexible micro-supercapacitors with an interdigital in-plane design, the method demonstrated here does not involve a complicated lithography process, toxic chemical treatments, expensive rigid template, and cumbersome fabrication of jettable and stable precursor ink, which provides a simple route for fabrication of flexible planar micro-supercapacitors with high-practicality and high-performance.

A series of quinoline derivatives were designed and synthesized as tyrosine kinase inhibitors. Exploration of the structure–activity relationships resulted in compounds that are potent in vitro. In addition, compound 10f was found to be a potent and selective Raf kinase inhibitor.

Correction for ‘Enhanced actuated strain of titanium dioxide/nitrile-butadiene rubber composite by the biomimetic method’ by Dan Yang et al., RSC Adv., 2015, 5, 65385–65394.