Preparation of Silica Nanosphere with Vertical Pore and Its Application in Oil-water Separation

Uniform monodispersed mesoporous silica nanospheres with vertical pores were successfully synthesized using chiral amphiphilic small molecule L-16Ala5PyClO4and solvents as dual templates via solgel transcription.The morphologies and pore sizes of silicas are adjustable by changing the type and amount of solvents in the reaction systems.With the increase of the organic solvent content,the morphologies of the obtained silica changed from nanospheres with vertical pore structures to nanosheets structures.When 1 mL of benzene,cyclohexane or toluene were used as solvents,only silica nanospheres were obtained,the BET surface areas of silica nanospheres reached 600.7,669.5,and 560.8 m^(2)/g,respectively.The pore sizes were 3.51,3.54,and 3.46 nm,respectively.Significantly,these ordered silica nanospheres/poly(vinyl alcohol-co-ethylene)(PVAco-PE)nanofiber membranes have high separation efficiencies(>99%)for n-hexane/water mixtures.

Preparation of Silica Radiation Pore and Its Application as Antimicrobial Carrier

Hollow silica nanospheres with radical pore on the surfaces were prepared using the assemblies of valine amphiphilic small molecule and benzene as double-templates through sol-gel method in tetramethylammonium hydroxide(25wt%)solution at the stirring rate of 1000 rpm.There are a lot of vertical pores on the surfaces of the hollow spheres after removing the templates in Muffle furnace at 550℃for 5 h.The sample was characterized using field-emission scanning electron microscopy,transmission electron microscopy,Brunauer-Emmett-Teller(BET),X-ray diffraction,etc.The diameter,the vertical pore size of the nanospheres and the BET surface areas are 30-100 nm,4.2 nm,and 570.5 m2/g,respectively.Because the high porosity and specific surface area,this kind of hollow sphere is the excellent antimicrobial carrier.The antibacterial activities of the silica nanospheres were evaluated by using a bacterial growth inhibitory assay.The experimental results show that the silica hollow spheres loaded with Ag+have a good bactericidal effect.

Preparation and Performance of Corona-proof Conductive Composite Coatings

Because of its merits,acrylic resin was chosen to improve the mechanical,conductive and hydrophobic properties.Carbon fiber powders (CF),carbon nanotubes (MWCNT),and nano-TiO_(2) were incorporated into the acrylic resin to prepare the corona-proof conductive composite coatings.The incorporation of CF and MWCNT may improve the conductivity and mechanical strength of the coatings.However,the addition of nano-TiO_(2) may increase the hydrophobicity of the coatings.Thus,the effects of different additives on the mechanical properties,conductivity,hydrophobicity and heat resistance of the conductive film were studied.The experimental results show that the incorporation of carbon fiber powders and multi walled carbon nanotubes can significantly improve both the conductivity and mechanical properties of the conductive coatings,and the addition of nano titanium dioxide can improve the hydrophobicity of the conductive film.

Preparation of Kenaf Biochar and Its Adsorption Properties for Methylene Blue

The toxic dyestuff's from printing and dyeing wastewater have caused serious damages to the ecological environ-ment,thus exploring effective methods to remove them having become a key topic.Here,a series of biochar sam-ples were synthesized form kenaf to adsorb methylene blue(MB),which was acted as the dye representative for the test of adsorption capacity due to the presence of abundant double bond and aroma tic heterocyclic ring.By tuning the raw materials and pyrolysis temperature,a super adsorption capacity about 164.21 mg·g^(-1) was obtained over the biochar that pyrolyzed at 700℃ with the kenaf fiber as raw material Through the physical adsorption,elemental analysis,FTIR spectra and NH_(3)-TPD,it was found the high surface area and pore volume of biochar played a key role in the adsorption of MB,and the acidic sites would also assist the adsorption process.Besides,the adsorption kinetic model was ftted and calculated,implying the MB physically adsorbed on the bio-char rapidly and then occurred chemical adsorption on the acidic sites.In addition,through KBC700 recycling experiments,it was found that kenaf biochar had a good binding force to MB,which effectively avoided secondary pollution.This work provides important insights for the adsorption mechanism of MB by biochar,also offers some guidance for the further synthesis of biochar from various biomass.

Preparation of Chiral Silica Nanostructures with Radial Pores through Single-templating Approach

A chiral low-molecular-weight gelator(LMWG) L-16Ala5PyPF6 was synthesized from L-alanine, which can cause physical gel in n-propanol, ethyl acetate, butylene oxide, water, benzene, 1,4-dioxane and chloroform. The sol-gel reactions were carried out in a mixture of stronger ammonia water and n-propanol at the volume ratio of 2:8. Single-handed twisted silica nanostructures with pore channels vertical to the wall surfaces were first prepared through a single-templating approach comparing with the reported double template method. The formation mechanism of radial pore structure was studied by transmission electron microscopy at different reaction time intervals, which indicated that the radial pore structure was formed via a structural transition in the sol-gel transcription process.

One-step Eco-friendly Fabrication of Antibacterial Polyester Via On-line Amination Reaction by Melt Coextrusion

The work is dedicated to develop a one-step eco-friendly method to prepare antibacterial polyethylene terephthalate(PET).We report a one-step eco-friendly method to manufacture antibacterial PET via on-line amination reaction by melt coextrusion.Beside evenly mixing of poly(hexamethylene guanidine)(PHMG)and PET in the melt coextrusion procedure,the amination reaction also occurred between PHMG and PET under high temperature(230-270℃).The antibacterial ability of composite PET showed obvious PHMG concentration dependence,and antibacterial activity reached more than 99%when PHMG content was 2.5 wt%.Moreover,LIVE/DEAD fluorescence test further confirmed that the composite PET could kill bacteria quickly and efiectively(within 30 min);while negligible cytotoxicity was observed to HSF and HUVEC cells.Onestep eco-friendly fabrication of composite antibacterial PET was accomplished by on-line melt coextrusion.The composite antibacterial PET has potential use in multiple fields to combat with pathogenic including textiles,packaging materials,decoration materials and biomedical devices,etc.

Organic Electrochemical Transistor based on Polypyrrole/ Crosslinked Chitosan/Nylon Fibers

Glutaraldehyde(GA)crosslinked chitosan(CHIT)was modified on nylon fibers.Afterwards,pyrrole was in-situ polymerized on the surface of the CHIT/Nylon fiber.The SEM and FT-IR results show that the functional fiber is successfully prepared,and the obtained polypyrrole(PPy)presents nanorods morphology on the fiber surface.The mechanical properties of the fibers were studied by Instron.The organic electrochemical transistors based on PPy/Nylon fiber,PPy/CHIT/Nylon fiber,and PPy/GA-CHIT/Nylon fiber as channels were prepared and their transistors performance was compared.It is found that PPy/GA-CHIT/Nylon fiber-based transistor has great output,transfer,transient curves,and excellent transconductance of 6.8 mS,providing a new platform for the field of wearable devices.Furthermore,the study introduces chitosan material with excellent biocompatibility,which makes prepared transistors also have potential applications in the field of biosensing.

Antimicrobial-free knitted fabric as wound dressing and the mechanism of promoting infected wound healing

Fibrous biomaterials are widely used in the design and fabrication of antibacterial wound dressings.Two strategies are used to make anti-infective dressings:antibacterial and probiotic therapies,which have potential biotoxicity and other side-effects.Herein,we report a new strategy for fabricating wound dressings to combat infection.Poly(4-methyl-1-pentene)(PMP) fabric can remove bacteria from infectious wounds through dressing changes based on its efficient bacterial adhesion.The maximum adhered count of S.aureus and E.coli on the PMP fabric was 1.63 × 106CFU/cm~2 and 4.77 × 105CFU/cm~2,respectively.In addition,the PMP fabric could inhibit the twitching motility of bacteria,which is beneficial for inhibiting infection.The ability of the PMP fabric to accelerate wound healing was demonstrated in vivo in a rat wound model.After treatment with the PMP fabric dressing,pathogenic bacteria in the wound were removed through dressing change;therefore,the wound exhibited better healing speed than when the commercial dressing was used.The low bacterial concentration effectively stimulated the expression of growth factors and suppressed wound inflammation,thereby accelerating wound healing.PMP fabric has three advantages:(1) it has been approved for use in clinical treatment by the Food and Drug Administration;(2) no antibacterial agent or probiotics were used;(3) the fabric could be manufactured through an industrial production process.These results indicate that the new strategy can be used in the design of new-generation wound dressings for antibacterial applications.

A scalable versatile methodology to construct micro/nano open-cell polypropylene foam with high oil adsorption capacity and speed

Oil pollution is a serious environmental and natural resource problem.Traditional adsorption materials for oil–water separation have limitations in terms of their preparation cost,reusability,and mechanical properties.Among the conventional adsorption materials,super-hydrophobic/super-lipophilic materials are easily contaminated by oil.In this study,polypropylene(PP)is used as a foam substrate to prepare an open-cell PP foam via hot pressing,supercritical CO_(2) foaming,and electron beam(EB)irradiation.The impact of EB irradiation dose on the open-cell content of PP foam can lead to cell wall rupture,resulting in an open-cell structure that enhances oil-water separation performance.At an absorbed radiation dose of 200 kGy,the PP foams exhibit optimal oil–water separation performance,cyclic compression stability,heat insulation,and preparation cost.The open-cell content of PP foam is increased to 86.5%,the adsorption capacity for diesel oil is 42.8 g/g,and the adsorption efficiency remains at 99.6%after 100 cycles of oil desorption in a complex pH environment.Meanwhile,cracks and nano-voids simultaneously promote the capillary action of oil,and the oil transport rate is 0.0713 g/(g·s).This study provides a new concept for the preparation of open-cell polymer foams that can meet the demand for high oil-absorption capacity under complex acid-base pH conditions.

Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting diversity.Herein,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral monomers.We successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription system.Leveraging the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine COFs.Crystallinity and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst employed.Under optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine COFs.This study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

Synthesis and luminescence properties of apatite-type red-emitting Ba_(2)La_(8)(GeO_(4))_(6)O_(2):Eu^(3+)phosphors

A new kind of apatite-type red-emitting Ba_(2)La_(8)(GeO_(4))_(6)O_(2):Eu^(3+)phosphor was prepared by high temperature solid-state method.The Rietveld analysis based on the powder diffraction data shows that Ba_(2)La_(8)(GeO_(4))_(6)O_(2):Eu^(3+)phosphors possess a pure apatite phase without any impurity.The emission spectrum of Ba_(2)La_(8)(GeO_(4))_(6)O_(2):Eu^(3+)phosphor consists of two bands,an orange emission band from 500 to 600 nm and a red emission band from 600 to 680 nm.By varying the amount of the doped europium ions from 0.02 to 0.14 mol,it is found that the luminescent properties of this rare earth phosphor are the best when the concentration of europium ion is 0.08 mol.The optimum concentration is eventually proved to be 0.08 mol.The Eu^(3+)doping dependent luminescence quenching can be further ascribed to dipole-quadrupole interactions.The quantum yield of Ba_(2)La_(7.92)(GeO_(4))_(6)O_(2):0.08 Eu^(3+)is 37.23%.The CIE analysis confirms a reddish emission in the near ultraviolet(n-UV)excitation.All these above properties of the phosphor can help in contribution of promoting white light-emitting diode.

Hierarchical CuO-ZnO/SiO_(2) Fibrous Membranes for Efficient Removal of Congo Red and 4‑Nitrophenol from Water

Hierarchical CuO-ZnO/SiO_(2)(CZS)nanofibrous membranes are designed and fabricated to remove Congo red and 4-nitro-phenol two common small molecular pollutants in water.The electrospun SiO_(2) fibrous membrane is serves as the substrate for hydrothermal depositing CuO-ZnO nanosheets.The CZS nanofibrous membrane shows good adsorption characteristics for Congo red due to the hierarchical morphology and the adsorption kinetics where isotherm follows the pseudo-second-order model and Langmuir model,respectively.The maximum adsorption capacity for Congo red is 141.8 mg/g.Moreover,the membrane exhibits excellent catalytic reduction activity for 4-nitrophenol under mild conditions and over 96%of the pollut-ants are degraded within 90 s.The CZS nanofibrous membrane has promising prospects in applications in water treatment and environmental protection because of the good flexibility,easy fabrication,excellent adsorption,and catalytic activity.

All‑Fiber Integrated Thermoelectrically Powered Physiological Monitoring Biosensor

Advanced fabric electronics for long-term personal physiological monitoring,with a self-sufficient energy source,high integrity,sensitivity,wearing comfort,and homogeneous components are urgently desired.Instead of assembling a self-powered biosensor,comprising a variety of materials with different levels of hardness,and supplementing with a booster or energy storage device,herein,an all-fiber integrated thermoelectrically powered physiological monitoring device(FPMD),is proposed and evaluated for production at an industrial scale.For the first time,an organic electrochemical transistor(OECT)biosensor is enabled by thermoelectric fabrics(TEFs)adaptively,sustainably and steadily without any additional accessories.Moreover,both the OECT and TEFs are constructed using a cotton/poly(3,4-ethylenedioxythiophene):poly(styrenesulfon ate)/dimethylsulfoxide/(3-glycidyloxypropyl)trimethoxysilane(PDG)yarn,which is lightweight,robust(90°bending for 1000 cycles)and sweat-resistant(ΔR/R0=1.9%).A small temperature gradient(ΔT=2.2 K)between the environment and the human body can drive the high-gain OECT(71.08 mS)with high fidelity,and a good signal to noise ratio.For practical applications,the on-body FPMD produced an enduring and steady output signal and demonstrated a linear monitoring region(sensitivity of 30.4 NCR(normalized current response)/dec,10 nM~50µM)for glucose in artificial sweat with reliable performance regarding anti-interference and reproducibility.This device can be expanded to the monitoring of various bio-markers and provides a new strategy for constructing wearable,comfortable,highly integrated and self-powered biosensors.

Floret-like Fe-N_(x)nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer boosting oxygen electroreduction

Fe–N_(x)nanoparticles-embedded porous carbons with a desirable superstructure have attracted immense attention as promising catalysts for electrochemical oxygen reduction reaction.Herein,we employed Fe-coordinated covalent triazine polymer for the fabrication of Fe–N_(x)nanoparticle-embedded porous carbon nanoflorets(Fe/N@CNFs)employing a hypersaline-confinement-conversion strategy.Presence of tailored N types within the covalent triazine polymer interwork in high proportions contributes to the generation of Fe/N coordination and subsequent Fe–N_(x)nanoparticles.Owing to the utilization of NaCl crystals,the resultant Fe/N@CNF-800 which was generated by pyrolysis at 800℃showed nanoflower structure and large specific surface area,which remarkably suppressed the agglomeration of high catalytic active sites.As expect,the Fe/N@CNF-800 exhibited unexpected oxygen reduction reaction catalytic performance with an ultrahigh half-wave potential(0.89 V vs.reversible hydrogen electrode),a dominant 4e–transfer approach and great cycle stability(>92%after 100000 s).As a demonstration,the Fe/N-PCNF-800-assembled zinc–air battery delivered a high open circuit voltage of 1.51 V,a maximum peak power density of 164 mW·cm^(-2),as well as eminent rate performance,surpassing those of commercial Pt/C.This contribution offers a valuable avenue to exploit efficient metal nanoparticles-based carbon catalysts towards energy-related electrocatalytic reactions and beyond.