Photocatalytic degradation is one of the most promising methods for addressing environmental issues without introducing pollution sources. Nonetheless, the majority of works are devoted to explore high-efficiency semiconductor photocatalysts, but the potential environmental risks in their application are usually neglected. In this work, an environmentally friendly vesicle-structured photocatalyst is rationally designed by employing magnetic layered double oxide-hollow spheres@antimony tin oxide as a core, phospholipid as membrane, and carbon nanotubes (CNTs) as channels, yielding a multi-structural material with robust organic pollutants photocatalytic degradation and mineralization ability. Materials characterization, computational modeling, and cytotoxicity tests suggest that under visible light irradiation, photogenerated charges can be rapidly generated and transfer in the core composite, and H2O2 can be effectively activated to generate hydroxyl radical for organic pollutants rapid degradation. The construction of phospholipid membranes and embedded CNTs not only maintains the photodegradation performance of the material, but also restrains its environmental risk. Such a synthetic approach advances the development of bionic photocatalytic materials. This work rationally designs an environmentally friendly vesicle-structured photocatalyst by employing magnetic layered double oxide-hollow spheres@antimony tin oxide as a core, phospholipid as membrane, and carbon nanotubes (CNTs) as channels, yielding a multi-structural material with robust organic pollutants photocatalytic degradation and mineralization ability. The use of bionic photocatalytic materials avoids potential environmental risks.image

In this work, a multiply-amplified peroxidase-like colorimetric strategy was proposed for the high-specific recognition and ultrasensitive detection of kanamycin (Kana). Based on two Kana-aptamer triggered sequential reactions, G-quadruplex (G4) and DNA (hairpins) modified Ni-Fe layered double oxides (LDOs) could be obtained simultaneously. Later, a three-dimensional G4/LDO frame networks, as a novel DNAzyme, with enhanced peroxidase-like catalytic activity was assembled through electrostatic interaction. This DNAzyme catalyzed 3,3',5,5'-tetramethylbenzidine oxidation for the colorimetric detection of Kana. The enhancement principle was discussed and the charge transfer process during the catalytic reaction was investigated. Under the optimal experiment conditions, the proposed method exhibited high sensitivity, where the linear range is from 10 fM to 10 nM (r(2) = 0.992), and the limit of detection is 3 fM (S/N = 3). The practicability of this assay was demonstrated by successfully application of residual Kana detection in genuine milk and urine samples. (C) 2021 Elsevier B.V. All rights reserved.

Cobalt sulphide/graphene aerogel nanocomposite (CGA) is successfully fabricated via a one-pot hydrothermal approach aided with ethylenediamine. CoS nanoparticles constructed by nanoplates are uniformly anchored and well distributed on the loose graphene aerogel framework. Owing to a synergistic effect combining nanosized CoS with graphene aerogel advantages, CGA as an anode material for lithium energy storage exhibits high reversible capacity, superior long-cycle property and excellent high-rate capability. Prominently, CGA maintains a high capacity approaching ~1100 mAh g −1 after 200 cycles at 100 mA g −1 . Even at 1 A g −1 , CGA still delivers a capacity of 460 mAh g −1 . This approach can be readily applicable to prepare other graphene aerogel-based nanocomposites as anode materials.

采用一步水热法,在乙二胺的辅助下,制备了硫化钴/石墨烯气凝胶(CoS/GA)复合材料.通过X射线衍射法(XRD)、扫描电镜(SEM)、电化学性能测试对材料进行了表征和测试.结果表明:制备的材料晶型规整,30～100 nm的CoS粒子均匀地分布在石墨烯气凝胶上.用作超级电容器时,在电流密度0.5 A/g时,CoS/GA复合材料比电容值达574 F/g,是纯CoS的1.4倍;充放电循环1000次后,比电容保持率为94.4％.硫化钴/石墨烯复合材料的电化学性能较好,具有较大的比电容和较好的循环稳定性,是一种可用于超级电容器的较有潜力的电极材料.

A cobalt sulfide (CoS)/graphene sheets (GS) nanocomposite was successfully synthesized through a simple one-pot hydrothermal route assisted by ethylenediamine. The crystalline phase, structure and morphology of this nanocomposite were systematically characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen (N₂) absorption-desorption isotherm, Raman spectroscopy and thermogravimetric analysis (TGA). The results revealed that the CoS nanoparticles with size distribution of 30-100 nm were highly dispersed on or well anchored in the creasy GS substrate. Integrating nanosized CoS compound and GS outstanding merits, the as-obtained CoS/GS nanocomposite as an anode material for lithiumion battery exhibited high reversible capacity, excellent long-cycle stability and remarkable high-rate capability, which were all superior to those of pristine CoS. Moreover, this nanocomposite maintained a high capacity of ˜600 mAh·g-1 after 200 cycles at a current density of 100 mA·g-1. The approach presented in this work is readily applicable to nanoparticle decoration of graphene sheets and preparation of other graphene-based nanocomposites as anode materials for lithium-ion batteries.

A cobalt sulfide decorated reduced graphene oxide (CoS/rGO) nanocomposite was successfully synthesized via a facile one-step hydrothermal route assisted by ethylenediamine. The crystalline phase, structure and morphology of the products were systematically characterized by x-ray diffraction, transmission electron microscopy, scanning electron microscopy, x-ray photoelectron spectroscopy, nitrogen (N2) absorption–desorption isotherm, Raman spectra and thermogravimetric analysis. The results show that CoS nanoparticles with the size of 30–100 nm are well dispersed on or anchored in the creasy rGO sheets substrate. Combining the CoS compound nature with the rGO outstanding characteristics, the as-obtained CoS/rGO as an electrode for a supercapacitor harvests high specific capacitance, excellent long-cycle stability and remarkable high-rate capability, which are all superior to those of pristine CoS. Importantly, this nanocomposite possesses a specific capacitance of 813 F g−1 at 0.5 A g−1 (about 2 times that of pure CoS) and excellent cycling stability with 91.2% capacitance retention after 1000 repetitive charge–discharge cycles. It is noteworthy that this approach can be readily applicable to the nanoparticle decoration of graphene sheets and the preparation of other graphene-based nanocomposites for supercapacitors.

To further improve carbonization efficiency of epoxy resin (EP) composites to form compact protective layers during combustion process, alkyl glycoside modified CuAl layered double hydroxide (CuAl-(APG)LDH) was designed and synthesized via one-step coprecipitation method, which was incorporated into EP matrix for preparing EP/CuAl-(APG)LDH nanocomposites. The results of XRD and TEM confirmed that EP nanocomposites with low incorporation of CuAl-(APG)LDH were exfoliated structures. The TGA results showed that the incorporation of CuAl-(APG)LDH remarkably increased the residues at 700 °C. The improved flame retardancy of EP/CuAl-(APG)LDH nanocomposites was proved by cone calorimeter test. The peak heat release rate, total heat release, peak smoke production rate and total smoke production value of EP/4 wt%CuAl-(APG)LDH nanocomposites dramatically decreased, which were attributed to the formation of hard and condensed residual layers on the surface of EP/CuAl-(APG)LDH nanocomposites.

To endow montmorillonite with excellent flame retardancy, montmorillonite (Mt) intercalation iron compounds (Fe-Mt) were synthesized and modified by phosphorylated chitosan (PCTS) to prepare PCTS modified Fe-Mt (PCTS-Fe-OMt). PCTS-Fe-OMt was further incorporated into epoxy resin (EP) for improving the fire safety of EP The results revealed that the interlayer spacing of Fe-Mt was expanded by PCTS, which resulted in well dispersion of PCTS-Fe-OMt in EP matrix. The TGA results showed that EP/PCTS-Fe-OMt nanocomposites exhibited much higher residues due to the excellent charring performance of PCTS-Fe-OMt. According to the cone calorimeter tests, the addition of 5 wt% PCTS-Fe-OMt made peak heat release rate, total heat release, peak smoke production rate, total smoke production values of EP observably decrease by 40.2%, 17.1%, 33.9% and 19.0%. Based on the above results, the improved flame retardancy and smoke suppression properties of EP/PCTS-Fe-OMt nanocomposites were attributed to the combination of iron compounds and phosphorylated chitosan on catalytic charring, thereby promoting the formation of swollen, continuous and compact char layers on the surface of polymer during combustion, eventually restraining the decomposition of polymers.

The polymer of MFR was used to fabricate Co9S8 encased in N,S-codoped graphene, which showed comparable electrocatalytic performance to Pt/C and RuO2.

Chemical and physical properties of silver nanoparticles (Ag NPs) are strongly influenced by NP size. The control of NP size is crucial for tuning or enhancing the properties of Ag NPs. In this paper, the size controlled Ag NPs have been achieved and dispersed on graphene (GE) sheets (Ag NPs/GE) using an eco-friendly and environment-friendly approach of thermal annealing method. The formation of size controlled Ag NPs has been restrained and it includes two stages. One is the formation of metallic Ag by reduction of Ag+ at low temperature (below 400 degrees C), wherein the ultrafine and highly dispersed Ag NPs can be obtained; another is growth and aggregation of Ag NPs at high temperature due to increasing surface diffusion coefficient of Ag atoms (above 400 degrees C). The Ag NPs/GE-400 presented an excellent antimicrobial activity due to the ultrafine size (similar to 9.6 nm), while the Ag NPs/ GE-700 exhibited an excellent SERS activity and sensitivity because of the appreciate size (similar to 95.8 nm). The Ag NPs/GE-500 (similar to 25.3 nm) presented the modest antimicrobial and SERS properties. Thus, our work may provide a reference to synthesize size-selected Ag NPs-based materials with a certain application using the thermal annealing method.

Flower-like CoS hierarchitectures were successfully synthesized through a hydrothermal route in the presence of ethylenediamine as ligand and structure-directing agent. The structure and morphology of the products were characterized by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy and \(\hbox {N}_{2}\) adsorption–desorption isotherm. Flower-like CoS hierarchitectures are constructed by two-dimensional CoS nanopedals interlaced and stacked with each other. When tested as electrode material for supercapacitors, the as-fabricated CoS delivers a specific capacitance of \(357~\hbox {F g}^{-1}\) at \(0.5~\hbox {A g}^{-1}\). After 2000 repetitive charge–discharge cycles, there is only 12.7% loss of the original specific capacitance. The results signify that the CoS supercapacitor possesses good electrochemical performances, suggesting its potential application in supercapacitor.

Abstract Cotton-like CoS cluster has been successfully synthesized via a simple one-step hydrothermal route assisted by diethylenetriamine (DETA) as a ligand and structure-directing agent. The structure and morphology of the product were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and N2 adsorption-desorption isotherm. The CoS sample which has a hexagonal phase without any impurities possesses a microscopic morphology made by cotton-like clusters. The as-fabricated CoS as a supercapacitor electrode presents desirable supercapacitive performance with a high specific capacitance (664 F∙g-1 at 0.5 A∙g-1), remarkable rate capability and excellent cycling stability (85.7 % specific capacitance retention after 1000 cycles), making it applicable as an electrode for high-performance supercapacitors.

We describe a facile one-step hydrothermal route to devise and synthesize polyhedron-shaped Co3S4 nanomaterial assisted by triethylenediamine (TEDA) as ligand and structure-directing agent. The structural characterizations indicate that the obtained products are Co3S4 polyhedral nanoparticles with irregular size, which interconnect and stack each other to construct an interlinked microstructure. When investigated for its supercapacitance property, the as-fabricated Co3S4 electrode material exhibits typical pseudocapacitance performances with a high specific capacitance of 1038 F g−1 at a current density of 0.5 A g−1 and excellent cycling stability of only 10.2% decay in its original specific capacitance after 1000 galvanostatic charge-discharge cycles, suggesting its potential application in supercapacitor. Importantly, this facile TEDA-assisted hydrothermal method can be universal to obtain other transition metal chalcogenides for supercapacitors.

The etched-platinum-silver aerogel (e-Pt-Ag gel) electrocatalysts with dendritic morphology were synthesized by chemical reduction and hydrothermal method, in which silver nanoparticles were removed by acid- and alkali-etching. X-ray diffraction (XRD), scanning electronic microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the composition, structure and morphology of e-Pt-Ag gel. The activity and stability of the catalysts for oxygen reduction reaction(ORR) were studied by cyclic voltammetry (CV) and linear sweeping voltammetry (LSV) methods. The results show that the e-Pt-Ag gel exhibits excellent ORR performance and favorable durability. In detail, the mass and specific activities of e-Pt-Ag gel at 0. 9 V are 166. 3 mA/mg(pt), and 0. 295 mA/cm(2), respectively, which are 2. 0 and 1. 8 times that of the commercial Pt/C catalyst [84. 9 mA/mg(pt), and 0. 163 mA/cm(2)]. Furthermore, the mass and space activities of the e-Pt-Ag gel only decay 6. 1% and 9. 1%, respectively, after 5000 electrochemical cycles, showing higher durability of the e-Pt-Ag gel compared with Pt/C(35%, 52. 1%)

In order to improve the oxidation resistance property of C/C composites, the C/C composites were modified by a novel sol-gel/solvothermal process. The suspension mixtures were prepared by mixing tributyl borate sol, ethanol, acetic acid and B 2O 3 powder. The as-modified C/C composites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscope (EDS) and X-ray photoelectron spectroscopy (XPS) techniques. The influences of the solvothermal temperature on the phase, microstructure and anti-oxidation property of the as-modified composites were investigated. Results show that the surface of the C/C composites are covered by a coating consisted of molten B 2O 3 and the internal microholes are occupied by B 2O 3. With the increase of solvothermal temperature, and the density of the coatings also increases. The anti-oxidation property of the modified C/C matrix is effectively improved with the increase of solvothermal treatment temperatures from 353 K to 433 K. The mass loss of the modified C/C composites is only 4.09% after oxidation at 873 K in air for 16 h.

In order to improve the oxidation resistance property of carbon/carbon composites, the C/C matrix was modified with a borate sol precursor and B4C micro-powders by a sol-gel integrating with a solvothermal process. The phase compositions, surface and cross-section microstructures of the C/C matrix modified by different B4C content were particularly investigated. Results show that the surface of the modified composites is covered by a coating composed of B2O3 and B4C, meanwhile, the internal micro-holes of the C/C composites are occupied by B2O3 and B4C. After oxidation in air at 973 K, the B2O3 glassy phase, due to the oxidation of B4C, seals the cracks and holes and effectively prevents C/C composites from oxidation. The weight loss of the modified C/C composites is only 2.21 % after oxidation in air at 973 K for 20 h.

Carbon/carbon (C/C) composites were modified with a borate sol–gel precursor by a novel process integrating sol–gel and solvothermal processes in order to improve the low temperature antioxidation properties of the C/C composites. Results show that the surface of the modified composites is covered by a molten B2O3 layer, and the oxidation resistance of the composites is improved with the extension of solvothermal time increasing from 12 to 48 h. After oxidation at 600°C for 6 h, the oxidation rates of the modified C/C composites are gradually decreased. The mass loss of the modified C/C composites at 600°C is due to the diffusion of oxygen along the molten B2O3 layer and the vaporisation of a small amount of B2O3.