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The design of highly efficient and stable photoelectrocatalysts for the hydrogen evolution reaction (HER) is critical to the large-scale application of clean hydrogen energy. Here, Cu3BiS3 nanoflowers (NFs) with photoelectrochemical (PEC) activity were synthesized via a solvothermal method under mild and low-toxic reaction conditions, and the Au nanoparticles (Au NPs) were loaded onto Cu3BiS3 NFs to improve the photoelectrocatalytic performance. Compared with pure Cu3BiS3 NFs, Au-Cu3BiS3 composites (A@C) exhibit a much higher photocurrent density (2 × 10−4 A cm−2) and greatly enhanced photoelectrocatalytic activity (2.31 μmol h−1), which are attributed to the enhancement in electron capture abilities, active sites and visible light absorption from the localized surface plasmon resonance effect (LSPR) of Au NPs. Furthermore, the excellent conductivity of Au NPs can effectively accelerate the separation and collection of photogenerated carriers. This work highlights a feasible strategy to improve the PEC activity of the Cu3BiS3 photoelectrocatalyst, and confirms the great potential of Au-Cu3BiS3 composites for hydrogen evolution applications.

Graphene sheets (GNS) surface-grown with polyaniline nanorods (GP) was wrapped by Polyaniline nanofibers (GP-P) via interfacial polymerization. The polyaniline nanofibers can act as structure coupling bridges and conductive wires for linking adjacent layers of GP together, thus accelerating the charge transfer among different GP layers and enhancing the specific capacitance and rate capability of the electrode materials. The specific capacitance of GP-P can reach 578 F/g at a current density of 1 A/g. An asymmetric supercapacitor based on GP-P cathode and a GNS anode was assembled. An energy density of 18.8 W h/kg at a power density of 1000 W/kg was obtained with a retention life of 93% after 10,000 cycles, suggesting a good cycling stability of the GP-P. The good capacitive performance of GP-P is contributed to the fact that the GP-P in the form of compact and multilayers' structures exhibits high interaction between the PANI nanofibers and GP, resulting in high resistance from mechanical damage during charge/discharge process.

The constricted visible light harvesting and undesirable rapid recombination of photogenerated e- and h+ set enormously hinder the activity of the photocatalysts. In this work, we design and develop two-dimensional/one-dimensional (2D/1D) S-g-C3N4/Co-NiS heterojunction with intimate heterointerface contact by self-assembly technique. The fast electron transportation of 2D S-g-C3N4 nanosheets (NSs) and the well-matched energy levels of bare S-g-C3N4 and 5% Co-NiS nanorods (NRs) cooperative support the transportation and separation of photo-carriers at the heterointerface of S-g-C3N4/Co-NiS. The as-fabricated samples were evaluated EDX, SEM, UV–vis, XRD, TEM, FTIR, XPS, BET, PL and transient photocurrent. Moreover, this well-defined construction boosts sunlight harvesting and exhibits a large surface area. Benefiting from the intimate coupling and structural features, the 20% S-g-C3N4/Co-NiS heterojunction attains a noteworthy photocatalytic methylene blue (MB) degradation rate of 100%, considerably improved than that of bare NiS (34%), 5% Co-NiS (57%) and pristine S-g-C3N4 (31%). Concurrently, the photocorrosion of bare S-g-C3N4 was suppressed by simultaneous integrating with NiS and engineering with cobalt, which was demonstrated through a chemical stability test with 6 consecutive experimental tests. Such outstanding enrichment in photocatalytic activity and chemical stability was primarily attributed to boosting spatial charge separation and synergistic effects of the 20% 2D/1D S-g-C3N4/Co-NiS nanocomposites (NCs). Antibacterial performance of 20% 2D/1D S-g-C3N4/Co-NiSNCs against 4 infectious species was evaluated in visible light radiance. Our results emphasize the great importance of the efficacious heterointerface blend of 2D/1D S-g-C3N4/Co-NiS NCs as a promising photocatalyst scheme for enhanced photocatalytic degradation of dye and disinfection of pathogens.

A new micro/nano-structured material, mesoporous CuS hollow spherical cap (HSC), was fabricated on the surface of a solution by template-induced interfacial reaction. The Cu2(OH)2CO3 microspheres modified with vinyl trimethoxy silane were floated on the mixed aqueous solution of ethanol and thioacetamide, and acted as the template and the copper source. At the solid-liquid interface thioacetamide reacted with Cu2(OH)2CO3 to produce CuS shells around the immersed part of the template, and then the mesoporous CuS HSC was obtain by removal of the template. Controlling the content of ethanol could systemically tune the immersed depth and the HSC height. Such HSCs displayed increased photocatalytic activity in degradation of methyl blue with the decrease of the HSC height. In addition to the conventional specific surface area, the activity regions accessible by light (light receiving region) were analyzed by optical simulation for the first time and considered an important factor in enhancing the photocatalytic activity of HSC structure. The present study not only shows a facile strategy to fabricate activity-tunable CuS HSC photocatalyst, but also establishes a relationship between the geometry of morphology and photocatalytic performance.

It is still a challenge to explore self-healable and reprocessable polysiloxane elastomer with improved mechanical strength and superior transparency. In this work, a self-healable and reprocessable polysiloxane elastomer with fine mechanical strength and optical transparency is facilely constructed by thiol-ene photopolymerization between thiol-functionalized silicone resin (MDT-SH) and vinyl-terminated polysiloxane and diboronic ester. The UV radiation intensity, molecular structure of MDT-SH and thiol/ene molar ratio play an important role in the thiol-ene photopolymerization and mechanical properties of polysiloxane elastomer. The damaged elastomer is completely repaired at 80 °C after 3 h, and the waste elastomer can be reprocessed into new items with 90% recovery of mechanical property. More importantly, its transmittance at 400–800 nm is higher than 95%, and it is almost unaffected by the healing process. This self-healable, transparent and tough polysiloxane elastomer has the potential to develop flexible electronics and wearable devices.

In this paper, we present a facile and one-step way for synthesizing Fe, N dual doped highly porous graphitic biomass carbon (FeNC) by using K2FeO4 to fulfill the activated process and catalytic graphitization of straws. The FeNC demonstrates hierarchically porous structure with large surface area of 1034 m2 g−1, Fe, N dual doping with certain amount of Fe-Nx, and graphitic structure. With these favorable features, the electrocatalytic activity for oxygen reduction reaction (ORR) reveals that the FeNC exhibits positively onset potential with highly comparable limiting current density when comparing with the sample using conventional KOH activated agent. In additional, the assembled Zn-air battery using FeNC as air-cathode catalyst delivers a maximal power density of 128.4 mW cm−2. Considering the abundance of straws on the earth and the low-cost and green prepared process, the present FeNC materials are highly promising in application in ORR catalysts for Zn-air battery and other energy-related fields.

Synergistic effect of AlN in combination with MWCNTs in AlN-MWCNTs/epoxy nanocomposites was found. Thermal conductivity of AlN-MWCNTs/epoxy nanocomposites increased obviously with the increase of AlN content. The added AlN can be filled in the networks of MWCNTs to form a more dense three-dimensional thermal conductivity network and provide more thermal conductivity channels. In addition to that, mechanical and flame-retardant properties of the nanocomposites were improved also. AlN-MWCNTs/epoxy nanocomposites presented optimum mechanical properties with the addition of 5∼7.5%wt AlN powder. With the addition of AlN powder in AlN-MWCNTs/epoxy nanocomposites, its LOI value is increased from 30.8% to 43.4% and UL 94 test achieves V-0 ranking.

Reported are the formation of rough particulate films from cross-linked diblock copolymer vesicles and nanotubes and the wetting properties of the resultant films. The diblock copolymers used were F66M200 and F95A135, where the subscripts denote the repeat unit numbers, whereas M, A, and F denote poly(2-cinnamoyloxyethyl methacrylate), poly(2-cinnamoyloxyethyl acrylate), and poly(2,2,2-trifluoroethyl methacrylate), respectively. The precursory polymers to F66M200 and F95A135 were prepared by atom transfer radical polymerization. In 2,2,2-trifluoroethyl methacrylate (FEMA), a selective solvent for F, vesicles and tubular micelles were prepared from F66M200 and F95A135, respectively. Photo-cross-linking the M and A blocks of these aggregates yielded hollow nanospheres and nanotubes bearing F coronal chains. These particles were dispersed into CH2Cl2/methanol, where CH2Cl2 was a good solvent for both blocks and methanol was a poor solvent for F. Casting CH2Cl2/methanol dispersions of these particles yielded films consisting of hierarchically assembled diblock copolymer nanoparticles. For example, the hollow nanospheres fused into microspheres bearing nanobumps after being cast from CH2Cl2/methanol at methanol volume fractions of 30 and 50%. The roughness of these films increased as the methanol volume fraction increased. The films that were cast at high methanol contents were superhydrophobic, possessing water contact angles of ∼160° and water sliding angles of ∼3°.

Synthesized and characterized were silica/amylose composite particles with interesting morphologies which we named as silica/amylase composite core–shell particles. Amylose is soluble in hot water. Ethanol addition to a volume fraction f EtOH of 75% caused amylose to aggregate into globules with diameters ∼50 nm and smaller. After ammonia and tetraethoxysilane (TEOS) addition, TEOS underwent sol-gel reactions in the presence of amylose. The reactions eventually yielded core–shell nanospheres with their core enriched by amylose and shell consisting mostly of fused SiO 2 -wrapped amylose or SiO 2 @amylose nanoparticles. Under a given set of experimental conditions, the equilibrium nanospheres had a well-defined size. The shell thickness increased as m S / m A increased, where m S denoted the amount of SiO 2 obtainable from the amount of TEOS precursor added and m A denoted the amylose amount. After pyrolysis of the nanospheres prepared at relatively high m S / m A values, interesting hollow silica particles with nano-sized porous walls were obtained.

We report the preparation of low-fluorinated homopolymer via heterogeneous atom transfer radical polymerization (ATRP) of 2,2,2-trifluoroethyl methacrylate (TFEMA) using 2,2′-bipyridine (bpy), N , N , N ′, N ′, N ″-pentamethyldiethylenetriamine (PMDETA), and tris(2-(dimethylamino)ethyl)amine (Me 6 TREN) as representatives for di-, tri-, and tetradentate amine ligands, respectively. The ATRP was better controlled, yielding polymers with controlled molecular weights and low polydispersities ( M w / M n ca. 1.11) when bpy was used as a ligand than when PMDETA was used. This was further supported by the results of our kinetic and chain extension studies. However, the ATRP of TFEMA had lower monomer conversions and gel formation when Me 6 TREN was used as the ligand. Further reported are the thermal-properties, as well as the surface properties of the films from the resulting polymers with different molecular weights.

Reported here is a novel approach toward efficient preparation of well-defined cylindrical brushes polymer (CBPs) with both hydrophobic and hydrophilic side chains connected to the linear backbone by interfacial “click” chemistry in two immiscible solvents. The CBPs with high grafting density of more than 95% and molecular polydispersity (Mw/Mn) less than 1.12 can be readily synthesized using present approach. On contrary, the CBPs synthesized from the “click” reaction in a single solvent in homogenous state have low grafting density of less than 55% and molecular polydispersity (Mw/Mn) more than 1.78. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

The cross-linked cassava xanthate (CCX) was synthesized and used to remove Cr6+ ions from aqueous solution. The influence of multiple factors on the sorption process, including pH, temperature, contact time, sulfur content, and sorbent/sorbate ratio, was quantitatively investigated. The sorption capacity of the CCX was confirmed under different conditions. The adsorption equilibrium was fitted to Langmuir and Freundlich isotherms. The Cr-containing cross-linked cassava xanthate (CCX-Cr) could be cyclically regenerated by HNO3 solution. The pyrolysis of the CCX and CCX-Cr was measured using Fourier transform infrared spectroscopy and thermo-gravimetric/differential thermal analysis coupling method. The CCX had higher percentage of the residues than the CCX-Cr due to the ion exchange mechanism in the adsorption process.

Cassava xanthogenate and their derivatives, as adsorbents to remove Pb2+ from aqueous solution, are studied based upon orthogonal factorial design. The structural and thermal properties, adsorption performance as well as equilibrium-kinetics are comprehensively investigated with multiple tools, such as Fourier transform infrared spectroscopy, thermal gravimetric analysis (TGA), and UV–visible spectrum technique. The influence of multiple parameters, including initial Pb2+ concentrations, compositions, pH values, and temperatures, on the adsorption performance is emphasized. The crosslinked cassava xanthogenate serves as an effective bio-sorbent to remove Pb ions from aqueous solution, allowing regeneration in dilute acid solution. The findings in this study are beneficial for the development of adsorbents from cassava waste biomass and may contribute to environment recovery in “nature-to-nature” manner. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39780.

We report here that the efficiency of the click chemistry between the terminal azide and alkyne groups of different polymer chains could be drastically increased with the addition of an optimum amount of water into a reaction system. That is, the efficiency was only slightly promoted by the addition of a small amount of water into the reaction mixture. However, the reaction efficiency was increased dramatically near the water volume fraction to lead the reaction mixture into nanosized phase separation. Further increasing in water content caused the polymer(s) to undergo macroscopic phase separation and the click reaction efficiency was decreased once again. The enhanced efficiency of click coupling reaction including conversion and rate was also demonstrated via in-situ 1H-NMR. The reaction kinetics as well as reaction rate constant for these reaction system with typical water content were also evaluated. This finding on enhanced click reaction is of practical value, because click reactions in polymer synthesis are generally more difficult to be carried out and proceed relative slowly at low yield in most case because of the strong steric hindrance effect from “large and long” polymer chains, as compared to “click” reactions which are employed for preparation of the low molecular weight organic compounds.

Novel cellulose derivatives were prepared from reacting (1R)-(+)-camphor-10-sulfonic chloride (CSC) with cellulose acetate (CA) in acetone and triethylamine. The reaction conditions, including reaction time and reactant molar ratios, were optimized. The structure of the products was confirmed by means of 1H NMR, 13C NMR, FT-IR and elementary analysis. The techniques were also used to determine the degree of the substitution of camphorsulfonyl groups (DSCS). The data calculated from 1H NMR, 13C NMR, percent grafting (G %) and elementary analysis coincided with those from chemical analysis. Compared to cellulose acetate, the cellulose derivatives exhibited decreased thermal stability, improved solubility in organic solvents and enhanced enantioselectivity towards tyrosine isomers. The solubility and enantioselectivity increased with increasing degrees of camphorsulfonyl substitution.