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In this work, the one-step stereochemical antimicrobial finishing of cotton textiles (CT) was achieved by the oxidative copolymerization of a dopamine-menthol derivative (DAM) and dopamine (DA). The obtained DAM-modified CT (P(DAM-co-DA)-CT) exhibited broad-spectrum microbial anti-adhesion properties against bacteria (E. coli and P. aeruginosa), including superbugs (MRSA and VREF), and fungi (A. niger, A. flavus, M. racemosus and P. chrysogenum). Because of its unique stereochemical antimicrobial mechanism, the obtained P(DAM-co-DA)-CT is a non-releasing antimicrobial material that causes no skin sensitization and exhibits good biocompatibility. The coating was also found to enhance the UV-resistant and mechanical properties of the CT. Furthermore, it displayed durable washing fastness and antimicrobial properties after the endurance of 30 laundering cycles. The observed achievements provide a broader understanding of stereochemical antimicrobial surfaces and endow this method with wider applications.

A strategy to improve its photocatalytic performance is still a challenge for the novel Sillen–Aurivillius perovskite type Bi4NbO8Br. Herein, novel Pt modified Bi4NbO8Br composites (Pt/BNB) with sufficient oxygen vacancies were successfully fabricated via a facile in situ chemical reduction method. For one thing, the deposition of Pt nanoparticles brings about a Mott–Schottky effect at the interface to accept photo-induced electrons, leading to an efficient charge separation. For another thing, the electronic metal–support interaction of Pt and Bi4NbO8Br decreases the formation energy of oxygen defects, which could serve as active sites for O2 activation. On account of the synergetic effect of Pt and oxygen vacancies, the dominant active species-photogenerated holes are accumulated on the surface of the photocatalysts, while the additional superoxide radicals are also involved. Hence, Pt/BNB performed with excellent photocatalytic activities in the degradation of wastewater contaminants, and the kinetic rate was 4.64, 10.21, 5.53, 9.80, 1.71 and 4.05 times, respectively, those of pristine Bi4NbO8Br towards methyl orange, rhodamine B, 2,4-dichlorophenol, p-nitrophenol, ciprofloxacin and tetracycline hydrochloride.

NiTiO3/Bi4NbO8Cl heterostructure photocatalysts were successfully synthesized by a mechanical mixing method. The crystal structure, morphology, optical properties and energy band structures of all samples were determined by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscope, ultraviolet–visible diffuse reflection spectra (UV–Vis DRS), and Mott–Schottky tests. The NiTiO3/Bi4NbO8Cl composites were observed to possess an improved activity in the photocatalytic degradation of organic dye rhodamine B (RhB) under irradiation. In particular, Bi4NbO8Cl modified with NiTiO3 (10% in weight) exhibits the best photocatalytic performance. The enhanced photocatalytic performance can be ascribed to the formation of intimate interfacial contact and type-II band alignment between NiTiO3 and Bi4NbO8Cl. From the results of photoluminescence spectra (PL), time-resolved decay spectra (TR-PL), photocurrent and electrochemical impedance spectroscopy, the rapid separation and transportation of photoinduced charge carriers were proved. In addition, the proposed mechanism for the enhanced photocatalytic activities is proposed in this paper.

A strong interfacial contact of heterostructured photocatalysts plays a key role in charges migration, thus promoting photocatalytic performance. Benefiting from the unique two-dimensional (2D) morphology and abundant terminals, 2D/2D “face-to-face” WO3·H2O/g-C3N4 heterostructured self-assemblies were fabricated employing tungsten oxide hydrate (WO3·H2O) nanoplates and graphitic carbon nitride (g-C3N4) sheets as precursors. Compared to pristine WO3·H2O and g-C3N4, the binary WO3·H2O/g-C3N4 heterostructures exhibit excellent photocatalytic performance towards water decontamination, using organic dye rhodamine B/methyl orange as probes. It is found that WO3·H2O/g-C3N4 with 20 wt% mass ratio (WHC-20) possesses the best photocatalytic activities, with about 3.05 times higher than that of pristine g-C3N4. The remarkable increase performance is attributed to the enhanced evolution of superoxide radicals (·O2−) via photoreduction in adsorbed oxygen molecules (O2−), which are promoted by efficient Z-scheme charges separation and rapid electrons transfer at 2D/2D interface. Given the low-cost, facile synthetic procedure and recycling stability, the heterostructured WO3·H2O/g-C3N4 could be served as a promising photocatalyst to deal with water contamination.

Metal-nitrogen doped carbon is a class of promising catalysts to replace Pt to catalyze the oxygen reduction reaction (ORR). Herein, a novel three-dimensional (3D) Fe-N-C nanosheets grown on interconnected carbon skeletons is fabricated by a facile route, i.e., in situ polymerization of aniline to obtain polyaniline nanosheets on 3D melamine foams and subsequent pyrolysis of the composites. The catalyst exhibits comparable catalytic activity but superior long-term stability to the commercial 20% Pt/C for the ORR in alkaline electrolyte in terms of the onset potential (1.01 V vs. RHE) and the half wave potential (0.86 V vs. RHE). The outstanding catalytic performance was ascribed to the populated active sites taking advantage of the large surface area, the superior electro-conductivity and the facilitated mass transportation by virtue of the unique hierarchically interconnected porous carbon structure. This work is expected to provide a new avenue to fabricate 3D interconnected porous composites for energy conversion and storage.

Utilizing more solar energy and suppressing recombination of photo-induced charges are primary issues for photocatalyst's design. In this work, BiOBr was introduced into CdTe/TiO2 to construct a novel ternary BiOBr/CdTe/TiO2 composite via a facile solvothermal method. The composition, morphologies, optical properties, specific area, and photocatalytic performances were all investigated in detail. The heterojunction among three-dimensional TiO2 particles, BiOBr and CdTe acts an interfacial channel to boost the charges migration. As a result, the ternary BiOBr/CdTe/TiO2 heterojunctions exhibited higher visible light photocatalytic activities on photo-decolorization of methyl orange (MO) than the pure TiO2 and the binary CdTe/TiO2 and BiOBr/TiO2. Furthermore, the ternary BiOBr/CdTe/TiO2 composites were converted into hollow structure, and showed the better photocatalytic performance, reaching 75% degradation towards MO in 120 min. This study provided an attractive thought to design highly efficient photocatalysts, which possessed a promising for wastewater purification.

Self-supported nanoporous metals are promising catalysts and battery materials due to their continuous channels, excellent conductivity and high surface area. In this work, we found that Cu2+ cations could promote the spontaneous formation of AgCl on Ag surface via microcell reactions. Applying a potential to the silver electrode promotes the surface enrichment of Cu2+ cations, and further speeds the formation of AgCl. After electro-reduced, AgCl was transformed to self-supported silver electrode with nanoporous structures, which shows good catalytic activity for the oxygen reduction reaction and electrochemical stability together with superior methanol tolerance property, compared to the pristine silver electrode. The approach used in this work provides an alternative way to prepare self-supported nanoporous metals.

Construction of semiconductor heterojunctions is an efficient strategy to improve photo-induced charges separation and thus enhance photocatalytic activities. Herein, g-C3N4/TiO2 heterostructures were prepared via a facile thermal procedure, with TiO2 nanorods as matrix and g-C3N4 as visible-light sensitizer. Heterojunctions formed while precursors cyanamide polymerized to g-C3N4 and protonated titanate nanotube (H-TNTs) dehydrated and shrinked to TiO2 nanorods. Notably, confined polymerization of g-C3N4 occurred at both external surface and internal space of H-TNTs with the assistant of vacuum treatment, while NH3 released from cyanamide decomposition yielded abundant oxygen vacancies (VO) in TiO2 nanorods. Compared with pristine TiO2 nanorods, the heterostructured g-C3N4/TiO2 nanorods possess 1.7 times more active in photocatalytic removal of organic dye Orange II. A mechanism was proposed for heterostructured g-C3N4/TiO2 nanorods, being attributed to synergistic increasing light harvesting by VO and charges separation by heterojunctions.

Multifunctional enzymatic nanomaterials (nanozymes) with good biocompatibility, strong enzymatic activity, and substrate specificity are the desired alternatives to natural enzymes. Here, the design of a peroxidase mimetic nanozyme capable of detecting and depleting glutathione (GSH) in the bacterial cells is presented. The nanozyme palladium-iron nanostructure decorated graphdiyne nanosheet (PdFe/GDY) was prepared by a facile hydrothermal approach. It can efficiently catalyze the decomposition of H2O2 to produce •OH by a peroxidase-like mechanism. Surprisingly, the PdFe/GDY nanozymes can detect GSH in bacteria with excellent specificity and ultra-low detection limit of 24.45 nM. Moreover, the PdFe/GDY nanozymes can consume GSH for bacterial disinfection with killing efficacy > 99.99%, promote wound healing and do not cause significant toxicity in vitro and in vivo. To our knowledge, this is the first example of a GDY-based nanozyme biosensor and antibacterial agent. Collectively, this work would be indicative to construct GDY-based nanozymes in clinical diagnosis and sterilization.

Organosilane-functionalized carbon dots (SiCDs) with green emission were prepared by one-step solvothermal method. Anhydrous citric acid and N-(2-aminoethyl)-3-aminopropyltrimethoxy-silane (KH792) ...

Bimetallic catalyst Ni–Fe/SiO2 microspheres were obtained by reducing bimetallic (Ni,Fe2+)3Si2O5(OH)4 microspheres with controllable morphology structure in situ under the hydrogen atmosphere at 650 °C, which are synthesized via one-step self-template method under hydrothermal conditions. The TEM images indicate the formation process of the different morphology and the synthesis conditions of bimetallic Ni–Fe silicate were obtained. Bimetallic catalyst Ni–Fe/SiO2 (reduced) hollow microspheres had the smaller surface area and the bigger pore diameter than that of (Ni,Fe2+)3Si2O5(OH)4 (unreduced) hollow microspheres because the reduction reaction under high temperature may make part pores in nanosheets collapsing and metal particles aggregating easily for the strong magnetism. For synergistic effect of nickel ion and iron ion, the reaction conditions of the chosen catalyst with higher activity were decreased from 140 °C–24 h + 180 °C −12 h for iron silicate hydroxide to 140 °C–12 h. Ni–Fe/SiO2 core-shell microspheres exhibited excellent catalytic activity with a conversion of nitrobenzene reaching 94% within 2 h, which is 82% higher than Fe/SiO2.

In this work, silane-functionalized carbon dots with green and red emission (G-SiCDs and R-SiCDs) were prepared via a one-step solvothermal method. Red LEDs were fabricated using a combination of R-SiCDs and blue LED chips since there have been few reports on red LEDs that have carbon dots as a converter. Also, different ratios of G-SiCDs to R-SiCDs were adjusted so they could serve as optical converters in trichromatic WLEDs. Compared to G-SiCD-based dichromatic WLEDs, the color rendering index (CRI), which represents the true color of irradiated objects, of R-SiCD- and G-SiCD-based trichromatic WLEDs was found to be significantly improved from 58 to 88. The CIE coordinates of the G-SiCD- and R-SiCD-based trichromatic WLEDs were very close to and were even the same as pure white light (0.33, 0.33). G-SiCDs and R-SiCDs have a similar functional alkoxysilane group, thus they will show good compatibility and can co-condense with each other to form a 3D cross-linking structure. What's more, environmental SiCDs have the potential to be luminescent and encapsulation layers simultaneously in trichromatic WLEDs. This strategy will help to avoid traditional compatibility problems between luminescent and encapsulation materials in WLEDs. The as-prepared polymerizable SiCDs could provide a new opportunity to simplify the preparation process and improve the optical performances of WLEDs.

Water electrolysis is a clean and effective strategy for mass production of hydrogen. Iron phosphide is a fascinating candidate for hydrogen evolution reaction (HER) among the reported Pt-free metal catalysts; however, the catalytic activity of FeP is far behind Pt. Herein, we prepared a highly efficient and durable mesoporous Mn-doped FeP (Mn-FeP) catalyst for HER via a facile and controllable synthesis route. It is manifested that Mn doping leads to improved electroactivity of mesoporous FeP in a wide pH range. For the mesoporous Mn-FeP catalyst, the overpotential is 69, 157, and 173 mV in H2SO4, PBS, and KOH electrolytes at 10 mA cm–2, respectively, which is 21, 40, and 54 mV less than that of its counterpart mesoporous FeP. Furthermore, it can be concluded that the enhanced HER activity of Mn-FeP is ascribed to both the appropriate thermoneutral hydrogen adsorption free energy and the accessible active sites thanks to the mesoporous structure from the density functional theory (DFT) calculation and th...

In order to improve the high-temperature oxidation resistance of the traditional phenolic resin binder, nickel nitrate was added into the phenolic resin as the catalyst precursor, while carbon nanotubes (CNTs) could be in-situ formed inside the pyrolytic carbons during the pyrolysis process. The influence of pyrolysis temperatures on the formation of CNTs in pyrolytic carbons was investigated. The results showed that CNTs with the diameter of 20–40 nm were formed in pyrolytic carbons, while the nickel nitrate and the gases released through the pyrolysis of phenolic resin were respectively served as the catalyst and the carbon sources. Meanwhile, the increased temperature could promote the formation of the CNTs, and further improve the graphitization degree and the high-temperature oxidation resistance of the pyrolytic carbons. The high-temperature oxidation resistance of corundum graphite composite materials could be effectively improved by using phenolic resin with nickel nitrate as the binder, which demonstrates it to be a promising binder for high-temperature application.

A mechanically robust, transparent, solvent-free, and self-cleaning coating (GPMS-DTDA/PFTS) was fabricated based on the co-hydrolysis/condensation of the Dibutyltin dilaurate, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (curing agent), while the different amount of 1H,1H,2H,2H-Perfluorodecyltrimethoxysilane were added to the system to reduce the surface energy of the coating. The morphology and properties of the polysiloxane-based coating were characterized by SEM, FTIR, UV–vis-NIR. The as-synthesized GPMS-DTDA/PFTS-based coating displays excellent performance with the hardness of 8H, superior adhesion (5B), high transmittance (95.2 %), hydrophobicity (CA: 107°) as well as outstanding properties of self-cleaning and weather resistance.

Hierarchical maghemite (γ-Fe2O3) microstructures have been synthesized by a facile and efficient templating approach involving the bottom-up formation and the subsequent thermal decomposition of the polymeric iron (III) acetate. The hierarchical microstructures of γ-Fe2O3 are derived from the template, which are assembled by porous nanobelts composed of nanocrystals. When evaluated as an anode material for lithium ion batteries, the hierarchical γ-Fe2O3 microstructures exhibit excellent electrochemical lithium storage performances including high reversible capacity (1300 mAh g−1 at 0.1 A g−1), excellent rate capability (383 mAh g−1 at 5 A g−1) and good cyclic stability (700 mAh g−1 after 100 cycles at 1 A g−1), The excellent performances are explored in terms of hierarchically porous structures, which promotes the fast and effective lithium ion transport, and buffer the large volume expansion during the charge and discharge cyclings.

Novel porous coordination polymers (PCPs) modified with sulfonic acid/phosphotungstic acid (PTA) were prepared by hydrothermal method via one-pot self-assembly. The materials were characterized by FTIR, XRD, TEM, SEM-EDS, N 2 adsorption/desorption, TG, NH 3 -TPD, etc., and have been used as solid acid catalysts for reproducible glucose transformation to 5-hydroxymethylfurfural (HMF) in environmentally friendly solvents. With PCP(Cr)-SO 3 H·Cr(III) as catalyst, over 99.9% glucose conversion and an excellent HMF yield of 80.7% were obtained at 180 °C for 4 h in water, with THF as the online extraction agent for HMF. In this system, the staple glucose material could successfully substitute the expensive fructose (HMF yield = 85.3%). A possible mechanism of glucose conversion and the formation procedure of byproduct were deduced and analyzed. The catalyst could be easily reused with good reproducibility and low wastage of active metal, showing a good prospect for high value applications of glucose.

Bifunctional lignosulfonate-based catalysts (LS-M) with Lewis acid and basic sites were designed and prepared by immobilizing metal ions on lignosulfonate. Catalysts were characterized by XRD, XPS, SEM, EDX, TEM, TGA, NH3/CO2-TPD and FTIR, and applied in transformation of carbohydrate biomass to furan derivatives (HMF/furfural) in mixed water/THF systems. With LS-Cr as catalyst, the optimized yields of HMF from cellulose, glucose and mannose were 46.3%, 60.4% and 68.8%, and that of furfural from xylan, xylose and arabinose were 40.2%, 73.1% and 51.6%, respectively. The catalysts could be easily recycled with negligible wastage of the active metal ions.

In this work, the self-doped polyaniline-molybdenum disulfide (SPAN-MoS2) nanocomposite with outstanding conductivity and synergistic electrochemical activity was prepared by ultrasonic exfoliating method. In the ultrasonic process, the negatively charged SPAN served as an intercalator to result in few-layers MoS2 nanosheets exfoliated from bulk MoS2. The obtained SPAN-MoS2 nanocomposite owns large conjugated structure and rich negative charge because of the strong π-π* stacking interaction and electrostatic repulsion, which can enhance the adsorption of some conjugate structured and positively charged biomoleculars, such as vitamin B2 (VB2). The results also displayed that the electrochemical responses were further affected by the mass ratio and the ultrasonication time.

Polysiloxane coatings prepared by pre-hydrolysis/condensation of methyltrimethoxysilane (MTMS), etraethoxysilane (TEOS), methyltriethoxysilane (MTES) and polydimethylsiloxane (PDMS) in the presence of acid solution were presented in this paper in order to explore their potential use as protective and self-cleaning agents for car surface. The hardness and adhesion on the substrate properties of coatings were thoroughly examined by pencil hardness tester and adhesion tester. Contact angle meter was used to measure the hydrophobic angle properties of coatings. All the properties of coatings were related closely to the composition of coating and the hydrolysis degree of organoalkoxysilane. We found that the Scratch hardness can be improved by the controlling of TEOS quality ratio and acidity conditions, while more dosage of MTMS, MTES and PDMS favor raising the hydrophobic angle. Excellent adhesion property of paint coat was obtained with the presence of γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH-560). Whatever, the best self-cleaning coatings with excellent hardness and adhesion on the substrate was sample A4 synthesized by a sol–gel process of low-cost organoalkoxysilane, prepared at the quality ratio of (MTMS):(TEOS):(MTES):(PDMS):(KH-560) of 8:7:4:4:4 and water-to-precursor quality ratio of 1:7. Finally, ambient-curable self-cleaning coating suitable for large area application was obtained. The scratch hardness and adhesion strength of the coatings was 3H and 0 after hardening with a high speed, respectively. The contact angle after UV aging of the coating was 92°. The transmittance of the coating exceeded 98.5%. Meanwhile, the coating has good resistance to solvent and weather resistance.

Porous Prussian blue (PB) films were successfully electrodeposited on Ni3Si2O5(OH)4 hollow nanosphere coated indium tin oxide (ITO) glass. Ni3Si2O5(OH)4 hollow nanospheres hydrothermally synthesized using SiO2 nanospheres as templates play a key role in the formation of porous PB films. The as-prepared PB films exhibit larger transmittance change, faster switching response and higher coloration efficiency than those of dense PB films directly electrodeposited on ITO glass. The enhanced electrochromic properties are attributed to the large specific surface area and porosity of the PB films which bring a high diffusion rate and short diffusion path length of ions.

Molybdenum disulfide (MoS2) has emerged as a promising electrocatalyst for catalyzing protons to hydrogen via the so-called hydrogen evolution reaction (HER). In order to enhance the HER activity, CTAB (cetyltrimethyl ammonium bromide)-incorporated MoS2 ultrathin nanosheets with high specific surface area and more catalytic active sites have been successfully synthesized via a facile surfactant-assisted hydrothermal approach. Adding CTAB to the hydrothermal process can effectively regulate both structural and electronic benefits by controllable disorder engineering and simultaneous CTAB incorporation in MoS2 catalysts, leading to a higher specific surface area, more catalytic active sites and better electrical conductivity for improving HER activity. The optimized CTAB-incorporated MoS2 ultrathin nanosheets exhibit excellent activity for HER with a small onset potential of 88 mV, a low Tafel slope of 55 mV dec−1, and relatively good stability.

Bi4NbO8Cl is a novel bismuth-based catalyst with a 2D sheet structure for photodegradation under visible light irradiation. However, Bi4NbO8Cl semiconductor has low quantum efficiency, as well as the photogenerated electrons (e-) and holes (h+) tend to recombine in a single semiconductor, thereby decreasing their degradation efficiency. Hence, in this work, Bi2O3/Bi4NbO8Cl 0D/2D heterojunctions containing Bi2O3 quantum dots were prepared to enhance the photocatalytic performance, in which e- and h+ were separated and transferred to different semiconductors for oxidation and reduction, respectively. Compared to bare Bi4NbO8Cl, the photocatalytic activity of 0.5 Bi2O3/Bi4NbO8Cl increases by 2.6 times in the degradation of Rhodamine B since the formation of heterojunctions. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) has confirmed the formation of heterojunction. The photoluminescence (PL), photocurrent, and electrochemical impedance spectra (EIS) tests indicate that the quantum efficiency has been improved. This research may be valuable for the industrial application of photocatalysts and provide a new idea for designing photocatalysts.

Electrocatalysts of NiCoFe hydroxides have been prepared successfully by a simple hydrothermal method, which show excellent electrocatalytic properties. (delivering 10 mA cm−2 current density at 230 mV, with a Tafel slope of 72.7 mV·dec−1). Furthermore, in order to further improve its electrocatalysis properties, the NiCoFe hydroxide is reprocessed by vulcanizing and acid etching, respectively. The electrocatalytic properties of the NiCoFe hydroxides after vulcanization is further improved (delivering 10 mA cm−2 current density at 200 mV, with a Tafel slope of 46.3 mV·dec−1). Similarly, acid etching is also a simple and effective method to promote the OER catalytic activity, which resulted in an exfoliation process and multiple defects. The NiCoFe LTHs is stripped into a thinner nanosheet structure, and the electrochemical analysis shows excellent electrocatalytic properties (delivering 10 mA cm−2 current density at 184 mV, with a Tafel slope of 37.8 mV·dec−1). Both vulcanization and acid etching show better oxygen evolution capability than the pristine LTHs in alkaline conditions with a small Tafel slope and good durability. This work will break a new and inexpensive path to promote the catalytic capability in an alkaline condition.

The strategy to improve the photocatalytic performance is still a challenge for the novel Sillen-Aurivillius perovskite type Bi4NbO8Cl. Herein, heterostructured Bi/Bi4NbO8Cl was fabricated via in-situ solvothermal method, without the additional introduction of Bi-sources. Simultaneously, the amount of oxygen vacancies (OVs) were increased, as the [Bi2O2] blocks released in the solvothermal process to serve as precursors for Bi particles. Due to the large work function of Bi, a Schottky barrier formed at the Bi/Bi4NbO8Cl interface, promoting photo-induced charge separation generated in the Bi4NbO8Cl semiconductor, supplying more holes for the organic compounds decomposition, which could be widely applied in water decontamination. Furthermore, the OVs facilitate the consumption of photo-induced electrons by assisting oxygen activation to produce superoxide radicals (·O2−), leaving more holes in the valence band of Bi4NbO8Cl, and thus result in the enhancement of Rhodamine B (RhB) degradation by 1.82 times over Bi/Bi4NbO8Cl photocatalysts. Through the synergistic effect of Bi and OVs, the Bi/Bi4NbO8Cl also exhibits enhanced photocatalytic performance towards various organic water-contaminants, such as methyl orange, acid orange 7, p-nitrophenol and tetracycline hydrochloride.

Molybdenum phosphide, as a promising electrocatalyst for the hydrogen evolution reaction (HER), its activity suffers from two main limitations: low active surface area and unsatisfactory electrical conductivity. Herein, inspired by the neural network, we construct a novel artificial neural network-like molybdenum phosphide composite (denoted as MoP@NC-MF), using three-dimensional (3D) melamine resin foams as the scaffold. The neural network-like MoP@NC-MF composite consists of carbon-wrapped MoP nanoparticles of abundant active sites as the “neurons” and N-doped carbon as the “axons”. The MoP@NC-MF composite exhibits high electrocatalytic activity and stability for HER with a low overpotential of 125 mV required to achieve a current density of 10 mA cm–2 and a small Tafel slope of 53.0 mV dec–1 under acidic conditions, which is one of the best HER electrocatalysts among the reported single molybdenum phosphide materials. Such a superior performance of the MoP@NC-MF composite is attributed to the unique ne...

The mesoporous nickel spheres catalysts with tunable chamber structures have been successfully prepared by liquid phase reduction of Ni3Si2O5(OH)4 microspheres at 120°C, which are synthesized by the reaction between Ni(Ac)2·4H2O and SiO2 microspheres via a self-template approach. This material with large BET surface area (158 m2/g) exhibits good catalytic activity and high selectivity in nitrobenzene hydrogenation reaction. The selectivity rate of the phenylamine reached to 99.85% and the conversion rate of the nitrobenzene was almost up to 100%, showing the potential application in the catalyst industry.

Roselike MoS2/nitrogen-containing carbon/graphene (MoS2/NC/G) hybrids were successfully synthesized via a facile polypyrrole (PPy)-assisted hydrothermal approach in combination with high-temperature calcination. The obtained MoS2/NC/G hybrids manifest roselike MoS2 composed of nanosheets coupled uniformly on NC/G nanosheets due to the strong interactions between MoS2 and the abundant nitrogen-containing functional groups of NC. When used as anode materials for lithium ion batteries, the MoS2/NC/G hybrids exhibit enhanced electrochemical energy storage performances compared to the bare MoS2 nanosheets, including high specific capacity (1570.6 mA h g−1 at 0.1 A g−1), excellent rate capability (704.8 mA h g−1 at 5 A g−1) and good cycling stability (96.4% capacity retention after 100 cycles at 0.2 A g−1). The enhanced lithium storage properties of the MoS2/NC/G hybrids can be ascribed to the boosted electronic conductivity arising from the novel hybrid nanostructures of MoS2/NC/G.

In this work, fabrication and characterization of ordered arrays of CNT/TiO2 nanotubes imbedded in porous anodic aluminum oxide (AAO) membranes were reported. The coaxial core–shell structures were exploited for the photocatalytic degradation of organic pollutants, such as methyl orange. The presence of the CNT greatly enhanced the efficiency of photocatalytic activity compared with the bare TiO2 nanotubes. The key achievement of this work is to fabricate ordered arrays of CNT/TiO2 composite nanotubes with coaxial core–shell structures by using a simple, convenient, and environmentally friendly process. Further application of this CNT/TiO2 hybrid material in many fields could be hopefully expected.

In this work, TiO2/MS (M = Pb, Zn) core–shell coaxial nanotube arrays were prepared by a simple method of liquid deposition using anodic aluminium oxide templates. The mechanism of the formation of TiO2/MS (M = Pb, Zn) coaxial nanotubes is discussed here. Compared to bare TiO2 nanotubes, TiO2/PbS and TiO2/ZnS composite nanotubes showed improved photocatalytic properties and analysis of such results was also conducted.

Bimetal Ni–Cu/SiO2 hollow spheres have been synthesized by reducing bimetal Ni–Cu silicate hollow spheres with a controllable morphology structure in situ in a hydrogen atmosphere under 750 °C, which are synthesized via a one-step self-template method using SiO2 spheres as templates under hydrothermal conditions. Along with prolonging the reaction time, the surface structure transforms from a sheet to a tube. Ni–Cu/silica had more activity as a catalyst than Ni/silica and commercial Raney Ni with the conversion of nitrobenzene reaching 95% within 1 h.

Nickel oxide (NiO) micro/nanoflowers were synthesized by hydrothermal treatment followed by calcination. The concentration of potassium persulfate (K2S2O8) plays a significant role in the formation of the NiO micro/nanoflowers. The NiO film annealed at 300 °C for 1.5 h exhibits fast coloration/bleaching response (1.3 s for coloration and 3.2 s for bleaching) and high coloration efficiency (49.8 cm2 C−1) due to the flower-like micro/nanostructures, showing a potential application in fast-response smart windows.

TiO2/WO3 composite nanotubes were synthesized in an anodic aluminum oxide (AAO) template by a sol–gel method. The prepared nanotubes were characterized by transmission electron microscopy, scanning electron microscopy, powder X-ray diffraction, and Brunauer–Emmett–Teller surface area. Using the nanotubes embedded in the AAO templates as catalysts, photocatalytic degradation of methyl orange aqueous solution was carried out under UV light irradiation. The results showed that the TiO2/WO3 composite nanotubes with the thickness about 50 nm could be successfully synthesized by this method. TiO2 showed anatase phase and WO3 displayed monoclinic phase. The composite nanotubes (TiO2/WO3) exhibited higher photocatalytic activity than the pure nanotubes (WO3 or TiO2). The possible reason for improving the photocatalytic activity was also discussed.

The efficacies of attapulgite clay (ATC)-, titanium dioxide (TiO2)- and silica gel (SG)-supported cobalt–cerium–boron (Co–Ce–B) substances as catalysts were investigated for the alcoholysis and hydrolysis of sodium borohydride (NaBH4) in ethanol–water solutions. Ce served as a helpful co-catalyst among the prepared Co–Ce–B catalysts, and the catalytic activity decreased in the following sequence: TiO2-supported > ATC-supported > SG-supported > unsupported. The effects of Ce/(Co+Ce) molar ratio, ethanol concentration, reaction temperature, NaBH4 concentration and NaOH concentration on the hydrogen production rate were investigated. For the ATC-supported catalyst, when the Ce/(Co+Ce) molar ratio was 10%, the catalyst exhibited the best catalytic activity. Optimal NaBH4 concentration, NaOH concentration and ethanol concentration to promote hydrogen generation rate was around 8 wt.%, 15 wt.% and 30 wt.%, respectively. It can be found that the addition of ATC greatly improved the recycle ability of the catalysts in the multi-cycle tests. The surface morphology of the catalysts before and after the recycle tests was studied from SEM images. The compositions of the catalysts were determined by XRD and EDS analyses. The occurrence of NaB(OH)4 in the alcoholysis by-product provided pertinent indications of ethanol recovery after the tests. The value of activation energy in the hydrogen generation process in the presence of ATC-supported Co–Ce–B catalyst was calculated to be 29.51 kJ/mol. An overall kinetic equation was also proposed.

Heterostructured photocatalysts play a significant role in the removal of contaminants by decreasing the recombination of the photo-induced charges. Herein, we presented novel TiO2/C/BiVO4 ternary hybrids employing a 2D layered Ti3C2 MXene precursor, overcoming the lattice mismatching of TiO2/BiVO4 binary heterostructures simultaneously. Raman and XPS analyses proved the strong coupling effects of TiO2, carbon and BiVO4 components, and the heterostructures were identified from high-resolution transmission electron microscopy results. Moreover, the ternary TiO2/C/BiVO4 composites exhibit excellent photocatalytic performance of Rhodamine B degradation, which is about four times higher than pure BiVO4 and twice that of binary TiO2/BiVO4 heterostructures, reaching a reaction constant of 13.7 × 10-3 min-1 under visible-light irradiation (λ > 420 nm). In addition, for the possible mechanism for dye elimination it was proposed that RhB molecule be directly oxidized by photo-induced holes (h+) on the BiVO4 components and superoxide radical ([Formula: see text]) generated from conduction band electrons of the heterostructures. This work will provide possibilities for developing visible-light responsive nanomaterials for efficient solar utilization.

Thermoplastic elastomers (TPEs) based on high-density polyethylene (HDPE)/waste ground rubber tire (WGRT) powder composites were prepared by melt compounding, and the composites were compatibilized by styrene–butadiene–styrene block copolymer (SBS). The effects of the SBS compatibilizer on mechanical properties, morphological properties and the Mullins effect of the composites were investigated systemically. Experimental results indicated that SBS had a good compatibilization effect on the HDPE/WGRT composites. Compared with HDPE/WGRT composites, the tensile strength and the elongation at break went through maximum values at a compatibilizer resin content of 12 phr. Morphological study showed that the interface interaction of the HDPE/WGRT composites compatibilized by SBS was strong, which contributed to the significantly improved mechanical properties. The Mullins effect results showed that the softening appeared after the first loading of the HDPE/WGRT and HDPE/SBS/WGRT composites, the maximum stress decreased at the later cycles, and the residual deformations in uniaxial loading–unloading cycles of the HDPE/SBS/WGRT sample were lower than those of the HDPE/WGRT sample, indicating that the elasticity of the HDPE/SBS/WGRT TPE was improved.

A novel water-swellable rubber (WSR) has been prepared by dynamically vulcanized ethylene–vinyl acetate copolymer (EVA)/chlorinated polyethylene (CPE)/nitrile butadiene rubber (NBR) blends where the cross-linked poly(sodium acrylate) (CPNaAA) was used as a super water-absorbent resin and dispersed in the NBR rubber. The mechanical properties, water-swelling behavior, weight loss and crystallization behavior of the prepared WSRs were investigated systemically. When the CPNaAA content was 20 phr above, the increase in CPNaAA dosage contributed to the decrease in mechanical properties. However, the WSRs showed strong water-swelling behaviors and the water-swelling ratio of WSRs with 50 phr CPNaAA was 669.3% at 120 h. The WSRs with 60 phr CPNaAA showed high water-swelling rate and achieved the equilibrium swelling at about 566.3% in 23 h. The secondary and third water-swelling behaviors of WSRs showed significantly rapid equilibrium swelling and remarkable decrease in weight loss. X-ray diffraction results revealed the increase in CPNaAA content would result in the reduction of crystalline structure content in EVA. Morphological study of etched surface showed that the CPNaAA particles were dispersed evenly in the WSRs and coated with cross-linked NBR rubber; moreover, field-emission scanning electron microscopic graphs showed the crystalline structure of EVA and clusters of flakes were dispersed on the etched surface of WSRs.

A novel water-swellable rubber (WSR) was prepared by dynamically vulcanizing polyvinyl chloride (PVC)/chlorinated polyethylene (CPE) blends where a crosslinked poly(sodium acrylate) (CPNaAA) was used as a super water-absorbent resin and dispersed in the CPE rubber. The mechanical, water-swelling, and morphological properties were investigated. The results showed that the dynamically vulcanized PVC/CPNaAA/CPE blends exhibited obvious elastomeric behavior and could be considered as thermoplastic vulcanizates (TPVs). The PVC/CPNaAA/CPE TPVs showed strong water-swelling ability, with the water-swelling ratio of the PVC/CPNaAA/CPE TPV with 30/60/70 weight ratio reaching 2400% at 200 h immersion. Moreover, compared with the first water-swelling behavior, the second and third water-swelling behaviors of the TPVs showed significantly improved water-swelling ratio and a remarkable decrease of weight loss. Morphological study showed that the interface interaction between the CPNaAA and CPE was weak. The CPNaAA part...

Thermoplastic elastomer (TPE) based on high impact polystyrene (HIPS)/ethylene-vinyl acetate copolymer (EVA)/waste ground rubber tire (WGRT) powder composites were prepared by melt-compounding, and the composites were compatibilized by styrene-butadiene-styrene block copolymer (SBS). The effects of SBS compatibilizer on mechanical properties and morphological properties of the composites were investigated systemically. Experimental results indicate that SBS had a good compatibilization effect on the HIPS/EVA/WGRT composites. Compared with HIPS/EVA/WGRT composites, the tensile strength and the elongation at break went through maximum values at a compatibilizer resin content of 12 phr, which were improved by 145% and 1280%, respectively. Morphology study shows that the interface interaction was strong in the HIPS/EVA/WGRT composites compatibilized by SBS, which contributed to the significantly improved mechanical properties. Payne effect could be found in the strain sweep of HIPS/EVA/SBS/WGRT composites, which was related to the variation of interface interaction. The increasing dosage of SBS compatibilizer in the HIPS/EVA/WGRT composites weaken the Payne effect and led to the slow decrease of storage modulus.

A chlorinated polyethylene rubber (CPE)/ethylene-vinyl acetate copolymer (EVA) (weight ratio = 70/30) thermoplastic vulcanizate (TPV) was prepared by dynamic vulcanization, with the TPV being reinforced by various amounts of zinc dimethacrylate (ZDMA). The effects of ZDMA content on the mechanical and morphological properties of the TPVs were investigated. Experimental results indicated that dynamically vulcanized CPE/EVA blends without ZDMA showed an elastomeric behavior when the CPE/EVA weight ratio ranged from 90/10 to 50/50. The mechanical properties of dynamically vulcanized CPE/EVA blends were enhanced remarkably by the incorporation of ZDMA, especially when the ZDMA content was 5 phr. The fracture surface morphology of the reinforced CPE/EVA TPVs was relatively rough and drawn fibers could be found clearly. There were many ZDMA particles dispersed on the etched surface of the reinforced CPE/EVA TPVs with diameters of below about 10 μm. Energy dispersive X-ray spectrometer (EDS) results showed that ...

Carbon nanofibers (CNFs) were prepared by chemical vapor deposition with Cu2O nanoparticles as a catalyst and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and infrared absorption spectrum (IR). Effects of hydrogen reduction, acid treatment and growth temperature on component and structures of CNFs were studied. According to the IR analysis, both ‒C‒C‒ conjugated bonds and ‒CH3, ‒CH2‒ saturated groups existed in carbon nanofibers. The degree of their oxidation was determined by the growth conditions. While the activity of the catalyst varied with temperature. The growth mechanism of CNFs was also discussed in this work.

A novel method was investigated to synthesize carbon fiber florets using copper tartrate catalyst precursors by catalytic chemical vapor deposition at 300 °C. Samples were obtained for different growth periods. On the basis of electron microscopy and X-ray diffraction characterizations, a growth model for the formation of fiber florets was proposed as well as the branching of fibers nearby copper catalyst particles. These findings could facilitate the understanding of the catalytic growth process of different carbon materials including carbon nanotubes and graphene under different reaction parameters.

Hexagonal phase flower-like Zn-doped CdSe (Cd1-xZnxSe, x = 0.3) semiconductor microstructures from the solid air-stable precursor have been achieved in the mixed solution of ethylenediamine (en) and ethylene glycol (EG) at 180°C for 12 hours. Characterized by powder x-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrum (EDS), and UV-vis absorption spectroscopy, it can be seen that the as-synthesized Cd0.7Zn0.3Se is hexagonal phase, and each flower-like Cd0.7Zn0.3Se microstructure is made up of many Cd0.7Zn0.3Se nanoflakes. From the UV-vis absorption spectrum of the product, it was observed that the optical band gap energies of flower-like Cd0.7Zn0.3Se microstructures shift toward shorter wavelengths compared with CdSe.

Orthorhombic single-crystalline cerium carbonate hydroxide (CeCO 3 OH) with one-dimensional (1D) microstructures has been successfully synthesized by a facile sonochemical reaction between cerous nitrate and urea. These 1D microstructures were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM). The as-synthesized CeCO 3 OH has uniform lengths and good dispersion. Synthetic parameters, such as the concentration of reagents, were found to have close relationship with the morphologies and sizes of the final products. The ultrasound-induced oriented attachment growth mechanism has been proposed for the possible formation mechanism of sample. Room-temperature photoluminescence of CeCO 3 OH samples with different morphologies has also been investigated.

The controllable synthesis of hexagonal pine-like Zn-doped CdSe (Cd 1− x Zn x Se, x = 0.1–0.3) nanotrees from the self-prepared mixed-metal precursors has been achieved by two facile steps: first, mixed-metal precursors ( x = 0.1–0.3) were prepared directly through precipitation reactions of stoichiometric cadmium acetate, zinc acetate and sodium selenite in distilled water under ambient condition; second, pure hexagonal phase pine-like Cd 1− x Zn x Se ( x = 0.1–0.3) nanotrees with different ratios were produced via solvothermal treatment of the precursor compounds in hydrazine hydrate at 180 °C for 12 h. The products were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrum (EDS) and UV–vis absorption spectroscopy. It was observed that the optical band gap energies of the as-synthesized Cd 1− x Zn x Se ( x = 0.1–0.3) nanotrees shift systematically toward shorter wavelengths with an increase of the Zn content.

Single-crystalline cerium carbonate hydroxide (CeCO3OH) with shuttle morphology has been successfully synthesized by a facile hydrothermal method with the aid of polyvinyl alcohol (PVA). The typical diameters of CeCO3OH shuttles (middle part) are about 800 nm, and the typical lengths are about several micrometers. The shuttle morphology of CeCO3OH was sustained after thermal decomposition−oxidation to CeO2. Furthermore, the influence of surfactant on the crystal morphologies and luminescence properties of the CeCO3OH products are investigated.

Fusiform hexagonal prism SrCO{sub 3} microrods were prepared by a simple solvothermal route at 120 deg. C, and characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FT-IR) spectroscopy. By controlling the content of ethylene glycol (EG), it was found that ethylene glycol (EG) played an important role in the formation of such SrCO{sub 3} microrods. Finally, effects of other solvents on the products, including 1,2-propanediol and glycerin, were also investigated.

ZnSe hollow spheres aggregated from nanoparticles with size of 60∼100 nm have been successfully synthesized via simple hydrothermal routes. NaOH and cetyltrimethyl ammonium bromide (CTAB) were used to control the shape and size, respectively. The as-prepared microspheres were characterized with powder X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The results indicate that the products are well dispersed and uniform. The effect of two additives was discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The core-shell SiO 2 /Mg(OH) 2 spheres were synthesized under ambient conditions, with the aid of polyethylene glycol (PEG) and sodium dodecyl benzene sulfonate (SDBS) to modify the morphology and dispersion of the products. The solid and hollow core-shell SiO 2 /Mg(OH) 2 spheres with different morphologies, such as convex-pointed, gyrus-like and honeycombed, controlled by the ratio of silica and magnesium chloride, were obtained and investigated by means of XRD, EDS, TEM and SEM. The formation mechanism of core-shell SiO 2 /Mg(OH) 2 structure was discussed in detail.