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Benzoquinone (BQ) is a desirable cathode for aqueous rechargeable batteries because of its high theoretical capacity and low cost. However, its application is seriously hindered by the high solubility of its discharge product in electrolytes, leading to rapid capacity decay. Here, we report a highly pyridine- and pyrrole-N-doped carbon cloth (NCC) with hierarchical pores as a promising host to anchor BQ and its discharge products. The resultant cathode (BQ-NCC) exhibits an ultrahigh initial capacity of 489 mA h gBQ−1 (excluding the capacity contribution of NCC) at 0.1 A g−1 and a long cycle life with a high capacity retention of 90.4% at 0.5 A g−1 after 500 cycles. Furthermore, a pouch-type cell with a capacity of ∼0.23 A h delivers an energy density of 136.1 W h kg−1 based on the total mass of BQ-NCC and Zn foil. Our study provides a novel strategy to construct high-performance aqueous Zn-ion batteries for potential practical applications.

Li-organic batteries (LOBs) are promising advanced battery systems because of their unique advantages in capacity, cost, and sustainability. However, the shuttling effect of soluble organic redox intermediates and the intrinsic dissolution of small-molecular electrodes have hindered the practical application of these cells, especially under high operating temperatures. Herein, a cross-linked membrane with abundant negative charge for high-temperature LOBs is prepared via electrospinning of poly(vinyl alcohol) containing halloysite nanotubes (HNTs). The translocation of negatively charged organic intermediates can be suppressed by the electronic repulsion and the cross-linked network while the positively charged Li

The wetting-patterned surfaces with alternate superhydrophobicity and hydrophilicity were designed and prepared by a facile solution growth of ZnO nanorods on selectively masked ZnO nanocrystals. T...

In the photoelectrochemical (PEC) water splitting for the hydrogen production, the fabrication of a stable and efficient photocatalyst semiconductor remains a challenge. CdS, which is one of most used chalcogenide materials, coupled with metal oxide semiconductor exhibit a generally low durability. TiO2 nanorods arrays (TNR) sensitized with CdS were synthesized via hydrothermal method and denoted as TNR-CdS. CdS deposition on TNR surface was controlled by regulating the hydrothermal reaction time. The samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electronmicroscopy, X-ray photoelectron spectroscopy, and UV-visible absorption. A high PEC performance as well as a great CdS sensitized TNR photoanodes stability were exhibited. These results could be due to the intimate contact between CdS and TNR, favoring a fast separation of photogenerated charge carriers. The optimal PEC performance was achieved when CdS was deposited on TNR for 10 h. Under AM 1.5G illumination at applied potential of 0 V vs Ag/AgCl, TNR-CdS (10 h) is found to have a photocurrent density of 6.5 mA/cm2 against 2.25 mA/cm2 for TNR. Additionally, TNR-CdS (10 h) presented a photoconversion efficiency of 2.5% at −0.4 V vs Ag/AgCl, while that of TNR was 0.9% at-0.35 V vs Ag/AgCl. TNR-CdS showed great stability with and without sacrificial reagent. These results were confirmed by electrochemical impedance spectroscopy measurements, where the rapid transfer/transport and separation of photogenerated charge carriers were highlighted.

Mn3O4 is viewed as an attractive candidate for rechargeable aqueous zinc-ion battery cathode materials due to the advantages of low cost, eco-friendly nature as well as high capacity. However, it faces inherently poor electronic conductivity and poor cyclability during battery cycling. To improve the electrochemical performance, Mn3O4 nanoparticles anchored on carbon nanotubes (CNTs@Mn3O4) were fabricated by a facile one-step solution process at low temperature. Benefiting from the synergistic effect of nanoscale Mn3O4 and 1D CNTs, the conductivity and electrochemical performance of Mn3O4 are significantly improved. The prepared CNTs@Mn3O4 nanocomposites deliver a discharge capacity of 310 mAh g-1 at 100 mA g-1, and maintain 123 mAh g-1 at 1000 mA g−1 after 500 cycles, demonstrating good rate capability and cycling performance as a promising cathode material for low-cost neutral zinc-ion battery.

Iodine/β-cyclodextrin (iodine/β-CD) inclusion complex was prepared via a simple saturated water solution route. The truncated cone-shaped and hydrophobic central cavity structure of β-CD could effectively encapsulate iodine molecules to confine the iodine within the electrode. The Li-iodine battery with iodine/β-CD cathode delivers the initial specific discharge capacity of 175 mAh g−1 at 0.1 C, and remains 164 mAh g−1 after 300 cycles owing to the favorable distribution and the retention of the iodine in the truncated cone-shaped β-CD matrix. Results demonstrate that β-CD as host electrode material could improve the stability of iodine-based cathode, showing great potential as a low-cost and facile cathode in Li-iodine batteries.

A series of N-isopropylacrylamide and methacrylate derivative random copolymers with various contents of cholic acid groups in the side chain are synthesized by free radical polymerization. These thermoresponsive random copolymers can organize themselves into large vesicles in water upon heating, accompanied by gradual phase transitions from transparent polymer solutions to turbid solutions and then to white hydrogels. The white vesicle hydrogels display non-elastic deformation and shrink. They can re-dissolve directly upon cooling. Further, X-ray diffraction results indicate the existence of crystalline regions on the vesicle membrane. Based on these results, the possible formation mechanism of the fiber-layer structures on the vesicle membrane is also discussed. It is noteworthy that the gel-forming temperatures of the resultant copolymers below 37 °C which indicate the vesicle gels may find applications as injectable implant systems for sustained drug delivery.

Cholic acid (CA) is a primary bile acid which possesses facial amphiphilicity and self-assembly ability. CA is slightly soluble in water, which makes it impossible to form the self-assembled structures spontaneously in aqueous solutions. To increase the water solubility, a cholic acid ester (CA-4EG) with a hydrophilic tail (tetraethyleneglycol, 4EG) was synthesized, which forms self-assembled structures in aqueous solutions. The self-assembled crystals of CA are obtained by acidic hydrolyzing the ester bond of CA-4EG. The rhombic hydrophobic tetramer structure units and fiber-layer structures are found in the self-assembled crystals of CA.

In this paper, hexagonal bipyramids and X- and polycrystal-shaped twins of cholic acid are acquired through the acidic hydrolysis of its ester hydrogel. The growth mechanism is proposed on the basis of the hydrophobic swallowtail-shaped tetramers found in the single-crystal structure.

We reported on the effect of an external magnetic field on the photovoltaic performance of Ru-bipyridyl dye N719 or CdS-sensitized ZnO nanorods-based solar cells (DSCs). At the short circuit, increases in photocurrent of ∼25% and ∼34% can be obtained at an external magnetic fields of less than 10 mT for N719 and CdS-DSCs, respectively, which in turn increase the energy conversion efficiency of ∼31% and ∼46%. This increase in photocurrent is attributed to an increase in the efficient separation of electron–hole pairs and a decrease in electron transport resistance in ZnO nanorods film under applied magnetic field. These interesting magnetic-field effects can lead to new potential applications in enhanced DSCs efficiency.

SnO2 nanosheet films about 200 nm in thickness are successfully fabricated on fluorine-doped tin oxide (FTO) glass by a facile solution-grown approach. The prepared SnO2 nanosheet film is applied as an interfacial layer between the nanocrystalline TiO2 film and the FTO substrate in dye-sensitized solar cells (DSCs). Experimental results show that the introduction of a SnO2 nanosheet film not only suppresses the electron back-transport reaction at the electrolyte/FTO interface but also provides an efficient electron transition channel along the SnO2 nanosheets, and as a result, increasing the open circuit voltage and short current density, and finally improving the conversion efficiency for the DSCs from 3.89% to 4.62%.

Nanostructured TiO2 with different hierarchical morphologies were synthesized via a warmly hydrothermal route. The properties of the products were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, N2 adsorption, UV-vis spectroscopy, etc. Two of the products, TiO2 1D nanorods (one-dimensional rutile TiO2 nanorods) and TiO2 3D0D microspheres (three-dimensional anatase TiO2 nanoparticle-assembled microspheres) exhibited superior photocatalytic effects on phenol degradation under UV illumination, compared with TiO2 3D1D microspheres (three-dimensional rutile TiO2 nanorods-assembled microspheres). Moreover, TiO2 3D0D was superior to TiO2 1D, as indicated by a 30% higher mineralization of dissolved phenol. Dihydroxybenze, 4,4'-dihydroxybiphenyl, benzoquinone, maleic anhydride, etc. were identified as the degradation intermediates. The excellent catalytic effect was attributed to the structural features of TiO2 1D nanorods and TiO2 3D0D microspheres, that is, a larger amount of surface active sites and a higher band gap energy resulted in more efficient decomposition of organic contaminants.

The synthesis of two new monomers containing a uracil unit and copolymers of the novel monomers with methyl methacrylate is described. Poly(styrene-acrylonitrile) (SAN) was modified by reaction with dicyandiamide in dry dimethyl sulfoxide, so that the acrylonitrile units were partially converted to 2,4-diamino-1,3,5-triazine moieties. The triazine rings in the terpolymer and uracil unit in the copolymer may form complementary triple hydrogen bonding sites. Blends of the copolymer containing uracil and terpolymer containing triazine ring were miscible owing to strong hydrogen bonding interaction between the two polymers. Miscibility and hydrogen bonding interaction of the blend system were investigated by DSC and FTIR.

Two novel methacrylate derivatives containing nucleic acid bases (uracil, thymine) were synthesized, and the copolymers of styrene and the new monomers were also prepared. The new monomers are more reactive than styrene. The synthesized copolymers were characterized by fourier transform infrared (FTIR) spectrometer, GPC and elementary analysis, and the result testifies the existence of the nucleic acid bases in the copolymers. The adsorption of phenol and 2-aminopyridine to copolymers in hexane was performed, and the result shows that much higher adsorption efficiency is achieved for 2-aminopyridine than that for phenol, suggesting that much stronger interaction between the copolymer and 2-aminopyridine than that between the copolymer and phenol. The interaction between the copolymers and phenol, 2-aminopyridine was studied by FTIR and the result shows that hydrogen bonding is taken place between the copolymers and phenol, 2-animopyridine.

Well-crystallized zinc oxide nanoscale tubular structures have been prepared by using the microwave irradiation method which does not need any templates, seeds, and surfactants. The ZnO nanotubes h...