Clarkdwyer8662
Fabricating perovskite single-crystal thin films (SCTFs) in controllable manner is the major challenge for the promising potential applications in optoelectronic devices. Although modifying the substrate surface is frequently used to realize the controlled growth of perovskite SCTFs, it is still unclear how the substrate condition affects the crystallization process. In this work, we systemically investigated the effects of the surface hydrophobicity of indium tin oxide substrates on the crystallization process of MAPbBr3 SCTFs prepared by the space-confined method. Comprehensive characterizations show that the surface morphology and crystallinity of SCTFs are improved, and the defect density is reduced when increasing the substrate hydrophobicity. The best MAPbBr3 thin film obtained has a full width at half-height of the rocking curve of the (001) crystal plane of 0.044°. The mechanism of the substrate hydrophobicity on the crystal growth is also discussed. These results will provide guidance to the controllable growth of high-quality SCTFs for perovskite SCTF devices.The contamination of water systems by heavy metals greatly threatens human health and ecological safety. An efficient adsorbent is critical for the removal of these contaminants. In this work, magnetic Ni3Si2O5(OH)4 nanotubes (NTs) have been synthesized via in situ hydrothermal reduction and further functionalized by grafting poly(4-vinyl pyridine) (P4VP) brushes on its surface via atom transfer radical polymerization. Characterizations by Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, and X-ray photoelectron spectroscopy proved that P4VP was successfully grafted on the surface of magnetic Ni3Si2O5(OH)4 NTs. The resultant Ni3Si2O5(OH)4-g-P4VP NTs are efficient nanosorbents for removing Cr(VI) anions from water. The Cr(VI) adsorption capacity of Ni3Si2O5(OH)4-g-P4VP NTs reaches 1.49 mmol/g at a pH of 3. The pseudo-second-order kinetic model and the Freundlich isothermal model are suitable to describe the adsorption process. The analysis using Weber-Morris and Boyd models indicates that both intraparticle diffusion and external film diffusion affect the Cr(VI) adsorption process. The adsorption enthalpy is estimated to be 18.37 kJ/mol. More than 90% of the Cr(VI) adsorption capacity of the Ni3Si2O5(OH)4-g-P4VP NTs remains after eight adsorption and desorption cycles.m-Cresol is an important chemical material, which is mainly derived from low-temperature coal tar. In this work, for separating m-cresol from coal tar model oil, two propylamine-based ionic liquids (ILs) propylamine formate ([PA][FA]) and propylamine acetate ([PA][Ac]) were selected as extractants. The selected ILs were synthesized and characterized by Fourier transform infrared (FT-IR) and 1H nuclear magnetic resonance (NMR) spectroscopy. The effects of temperature, mass ratio of IL to model oil, and separation time on the separation efficiency of m-cresol were explored. The separation efficiency (SE) and distribution coefficient (D) were calculated from the experimental data to assess the separation performance of [PA][FA] and [PA][Ac]. The results showed that propylamine formate was a promising extractant with the separation efficiency of 97.8% and distribution coefficient of 27.59 at 298.15 K and mIL/moil = 0.2. In the meantime, molecular dynamics (MD) simulations were employed to comprehend the interaction mechanism, from which the noncovalent interaction energy (IE), radial distribution function (RDF), spatial distribution function (SDF), and averaged noncovalent interaction (aNCI) were calculated. The results showed that both cation and anion formed hydrogen bonds with m-cresol and the anions played a leading role with electrostatic interaction energy in separating m-cresol. In addition, the regeneration and reuse of the ionic liquids were explored.We have prepared yttrium (Y)-doped hydrogen titanate nanorods (HTN) by a microwave-assisted hydrothermal method. Y-doped HTN showed much improved photocatalytic activities for both H2 evolution and dye decomposition. H2 production from a methanol-water solution under UV-visible light for 7 h was enhanced by a factor of 5.5 with 1 wt % Y-doping. Doping with Y3+ ions reduced the band gap of HTN by ∼0.28 eV and induced new phases of anatase and rutile. High photocatalysis by Y-doping was attributed to enhanced light absorption (smaller band gap) and effective charge separation (heterojunction). To optimize H2 production, a series of experiments examining effects of doping concentrations and non-noble surface metal (e.g., Ni, Cu, Co) loading were carefully performed. Y-doping in this work is a new and promising approach for synthesizing highly active HTN by producing the HTN/rutile/anatase heterostructure within the one-pot method.This paper presents a peptide-mediated immunomagnetic separation technique and an immunofluorescence quantum dot technique for simultaneous and rapid detection of Escherichia coliO157H7, Staphylococcus aureus, and Vibrio parahaemolyticus. First, three peptides that can specifically recognize the three foodborne pathogens were combined with magnetic nanoparticles to form an immunomagnetic nanoparticle probe for capturing three kinds of target bacteria and then added three quantum dot probes (quantum dots-aptamer), which formed a sandwich composite structure. When the three quantum dot probes specifically combined with the three pathogenic bacteria, the remaining fluorescent signal in the supernatant will be reduced by magnetic separation. Therefore, the remaining fluorescent signal in the supernatant can be measured with a fluorescence spectrophotometer to indirectly determine the three pathogens in the sample. The linear range of the method was 10-107 cfu/mL, and in the buffer, the detection limits of E. coliO157H7, S. aureus, and V. parahaemolyticus were 2.460, 5.407, and 3.770 cfu/mL, respectively. In the tap water simulation, the detection limits of E. coliO157H7, S. aureus, and V. parahaemolyticus were 2.730, 1.990 × 101, and 4.480 cfu/mL, respectively. In the milk simulation sample, the detection limits of E. coliO157H7, S. aureus, and V. parahaemolyticus were 6.660, 1.070 × 101, and 2.236 × 101 cfu/mL, respectively. The method we presented can detect three kinds of foodborne pathogens at the same time, and the entire experimental process did not exceed 4 h. It has high sensitivity and low detection limit and may be used in the sample detection of other pathogens.A novel ionic liquid immobilized on a magnetic polymer microsphere catalyst is reported in this paper. The obtained core-shell-shell catalyst consisted of magnetic nanoparticles (MNPs) as the core, catalytic inert St-co-DVB as the intermediate protective layer, and cross-linked polyaryl imidazole ionic liquids as the active catalytic layer located at the outermost [Im[OH]/MNPs@P(St-DVB)@P(VBC-DVB)]. This catalyst exhibited a high ion-exchange rate (64.65%), high saturation magnetic strength, and excellent acid and alkali corrosion resistance. In the catalyzed Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate, the conversion of benzaldehyde maintained at 92.1% during six times reuse. Optimizing the materials of the protective layer and regulating the thickness of the inert protective layer decreased the corrosion ratio of MNPs in acidic media from 44.82 to 0.44%. Adjusting the thickness of the catalytic layer realized excellent catalytic activity (97%) and high magnetic response performance. In summary, introducing an inert protective layer to the structure of ionic liquids immobilized on the magnetic polymer microsphere catalyst, regulating its thickness, and optimizing its structure achieved a catalyst with high activity, excellent stability, and easy magnetic separation.Bacterial infections are the most common type of clinical infection. The abuse of clinical antibiotics has led to the frequent appearance of drug-resistant strains and even some super bacteria. In this study, we synthesized Poly(MTZ) n -(DMAEMA) m polymer micelles with cations on the surface. The synthesis of this novel polymer comes in two steps. First, Poly(MTZ) n was synthesized with metronidazole (MTZ) referred as the macromolecular chain transfer agent and v-501 as the initiator for initiating the polymerization of 4-cyanopentanoic acid dithiobenzoate. Then, novel polymer micelles were synthesized with Poly(MTZ) n referred as the macromolecular chain transfer agent and v-501 as the initiator for initiating the polymerization of the monomer 2-(dimethylamino) ethyl methacrylate, which could adsorb to the negatively charged bacterial surface via electrostatic interaction and enhance bactericidal activity. Scanning electron microscopy showed that the micelles could be accurately targeted to the surface of bacteria, and the zone of inhibition assay confirmed that the micelles could enhance the sensitivity of bacteria to drugs. Hence, Poly(MTZ) n -(DMAEMA) m polymer micelles will have potential use for the clinical treatment of anaerobic infections in the future.Star-shaped three-dimensional (3D) twisted configured acceptors are a type of nonfullerene acceptors (NFAs) which are getting considerable attention of chemists and physicists on account of their promising photovoltaic properties and manifestly promoted the rapid progress of organic solar cells (OSCs). This report describes the peripheral substitution of the recently reported highly efficient 3D star-shaped acceptor compound, STIC, containing a 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (IC) end-capped group and a subphthalocyanine (SubPc) core unit. The 3D star-shaped SubPc-based NFA compound STIC is peripherally substituted with well-known end-capped groups, and six new molecules (S1-S6) are quantum chemically designed and explored using density functional theory (DFT) and time-dependent DFT (TDDFT). Density of states (DOS) analysis, frontier molecular orbital (FMO) analysis, reorganization energies of electrons and holes, open-circuit voltage, transition density matrix (TDM) surface, photophysical c8.77 nm (in chloroform), and highest Voc = 1.90 V with respect to HOMOPTB7-Th-LUMOacceptor. Our results suggest that the selected molecules are fine acceptor materials and can be used as electron and/or hole transport materials with excellent photovoltaic properties for OSCs.To improve the resistance to CO2 corrosion of oil well cement, soap-free emulsion polymerization was used to prepare a soap-free latex (PSAC) with sodium styrene sulfonate (SSS) and nano-SiO2 (SSS/SiO2) as the ionic copolymer emulsifier. The effects of SSS/SiO2 on the performance, thermal stability, and latex particle morphology of the PSAC were investigated through zeta potential, TGA, and TEM measurements, respectively. The carbonation resistance properties of cement with PSAC were evaluated, and the anticorrosion mechanism of the PSAC cement was determined by SEM, EDS, XRD, and 29Si NMR analyses. The results showed that the PSAC particle size was uniform, the particles were monodispersed, and they had a typical core-shell structure and good heat resistance. The carbonation resistance test results showed that after 60 days of corrosion, the corrosion depth of the cement with 12.0% PSAC content was only 2.16 mm, the permeability was 0.0018 mD, and the decrease in the compressive strength was 6.65%. The porosity in the cement was reduced significantly, and the pore volume (>50 nm) of the cement was reduced by 0.