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The fate of organic pollutants in the environment is influenced by several factors including the type and strength of their interactions with soil components especially SOM. However, a molecular level answer to the question “How organic pollutants interact with SOM?” is still lacking. In order to explore mechanisms of this interaction, we have developed a new SOM model and carried out molecular dynamics (MD) simulations in parallel with sorption experiments. The new SOM model comprises free SOM functional groups (carboxylic acid and naphthalene) as well as SOM cavities (with two different sizes), simulating the soil voids, containing the same SOM functional groups. To examine the effect of the hydrophobicity on the interaction, the organic pollutants hexachlorobenzene (HCB, non-polar) and sulfanilamide (SAA, polar) were considered. The experimental and theoretical investigations explored four major points regarding sorption of SAA and HCB on soil, yielding the following results. 1—The interaction depends on the SOM chemical composition more than the SOM content. 2—The interaction causes a site-specific adsorption on the soil surfaces. 3—Sorption hysteresis occurs, which can be explained by inclusion of these pollutants inside soil voids. 4—The hydrophobic HCB is adsorbed on soil stronger than the hydrophilic SAA. Moreover, the theoretical results showed that HCB forms stable complexes with all SOM models in the aqueous solution, while most of SAA–SOM complexes are accompanied by dissociation into SAA and the free SOM models. The SOM-cavity modeling had a significant effect on binding of organic pollutants to SOM. Both HCB and SAA bind to the SOM models in the order of models with a small cavity > a large cavity > no cavity. Although HCB binds to all SOM models stronger than SAA, the latter is more affected by the presence of the cavity. Finally, HCB and SAA bind to the hydrophobic functional group (naphthalene) stronger than to the hydrophilic one (carboxylic acid) for all SOM models containing a cavity. For models without a cavity, SAA binds to carboxylic acid stronger than to naphthalene. [ABSTRACT FROM AUTHOR]

Abstract: In this communication, we report on the solvothermal preparation of spinel ZnCo2O4/N-doped carbon nanotube (ZnCo2O4/NCNT) composite. As a novel oxygen reduction reaction (ORR) electrocatalyst, the ZnCo2O4/NCNT composite shows high activity via a four-electron pathway in alkaline solution. Such catalyst also exhibits superior methanol tolerance ability and durability over commercial Pt/C catalyst. [Copyright &y& Elsevier]

Abstract: In this paper, we demonstrate the first use of BCNO nanoparticles (BCNO NPs) as a novel highly efficient fluorosensor for Cu2+ detection with high selectivity. The detection process is ultrafast and can be completed within 2min, and the detection limit is 0.1μM. We also show the practical use of this sensor for Cu2+ determination in real water samples. [Copyright &y& Elsevier]

Abstract: Poly(o-anisidine) (POAS)/silverized multiwall carbon nanotubes (POAS–MWCNTs/Ag) composite was prepared by adsorption of POAS on the surface of MWCNTs by solution method. This research demonstrated that it was possible to metalized MWCNTs and uses a polymer as a substitute for polyaniline (PANI) to synthesize MWCNTs/conducting polymer nanocomposites by one-step easy mixing of solutions. The resulting composite was characterized using SEM; TGA and fourier transform infrared spectroscopy (FTIR), X-ray spectroscopy. The electrical resistivity of the composites was studies and it was found unusually higher conductivity than that of pure POAS and MWCNTs and it was 5S/cm. All the results demonstrated a facile route to the synthesis of POAS–MWCNTs/Ag composites, possessing good electrical conductivity and outstanding thermal stability at high temperature. [Copyright &y& Elsevier]

Abstract: In this article, for the first time, two-dimensional hybrid mesoporous Fe2O3–graphene (mFe2O3–G) nanostructures were developed as a peroxidase mimetic with catalytic activities superior to those of mFe2O3, G, and previously reported Fe-based peroxidase mimetics. The high-surface-area mFe2O3 not only offers a large number of catalytically active sites, but also facilitates the diffusion of 3,3,5,5-tetramethylbenzidine (TMB) and H2O2 toward G surface. On the other hand, G is π-rich and thus favors the adsorption and enrichment of TMB within these pores. These synergistic effects lead to highly improved catalytic performances. Based on these findings, a simple, rapid, and highly sensitive and selective optical detector of glucose has been developed and demonstrated in buffer solution with a pretty low detection limit of 0.5μM. In addition, this nanosensor is reusable and can also be used for glucose detection in diluted serum. [Copyright &y& Elsevier]

Abstract: In this paper, a novel and highly sensitive DNA sensor based on biopolymer is presented. This polydopamine nanospheres-based sensing platform exhibits high selectivity and sensitivity with a detection limit of 5nM and the sensitivity of this sensing platform increases with increased temperature. [Copyright &y& Elsevier]

Abstract: In this communication, for the first time, we demonstrate the electrodeposition of Ni3S2 on ZnO (ZnO@Ni3S2) array supported on nickel foam. We further demonstrate the direct use of ZnO@Ni3S2 array as a binder-free electrode material for supercapacitors and this electrode exhibits a very high specific capacitance of 1529 F g−1 at a current density of 2 A g−1, good rate capability and cycling stability. [Copyright &y& Elsevier]

Abstract: In this paper, we demonstrate the preparation of reduced graphene oxide (rGO) decorated with FeF3 nanoparticles (FeF3NPs) by adding FeF3 aqueous solution to the rGO ethanol/water dispersion. The obtained FeF3/rGO nanocomposite is further tested as a cathode material for rechargeable lithium batteries and found to have high discharge capacities, good rate capabilities and cycling performance. It can deliver a high discharge capacity of 476mAhg−1 at a current density of 50mAg−1 in the voltage range 1.0–4.5V. It still delivers a discharge capacity of 146mAhg−1 with 81% capacity retention after 50 charge–discharge cycles under a current density of 1000mAg−1 in the voltage range 1.7–4.5V. [Copyright &y& Elsevier]

Abstract: The present communication reports on the first electrodeposition of Ni(OH)2 on ZnO array supported on Ni foam. When applied as a binder-free electrode material for pseudocapacitive energy storage, the resulting ZnO@Ni(OH)2 array exhibits a high specific capacitance of 2028Fg−1 at a current density of 10Ag−1 with good cycling stability. Meanwhile, the array exhibits a superb rate capability. Even at an extremely high current density of 100Ag−1, the array still shows a very high specific capacitance of 1059Fg−1. [Copyright &y& Elsevier]

Abstract: The present communication reports on the first preparation of Ni(OH)2 nanoflakes array on Ni foam, carried out by hydrothermal treatment of Ni foam in acidic medium without the presence of extra nickel salt. We further demonstrate the application of such Ni(OH)2/Ni foam as a binder-free electrode material for supercapacitors. It is found that it can deliver high capacities of 1228F/g and 918F/g at 5A/g and 30A/g, respectively, with excellent cycling stability. [Copyright &y& Elsevier]

Abstract: In this communication, for the first time, we demonstrate the fast and facile preparation of porous FeF3 nanospheres using solvent exchange from FeF3 aqueous solution to ethanol. We further demonstrate the use of such FeF3 nanospheres as cathode materials for rechargeable lithium-ion batteries with good rate capability and cycling performance. [Copyright &y& Elsevier]

Abstract: The article reports on the microwave-assisted rapid green synthesis of photoluminescent carbon nanodots (C-dots) with diameters in the range of 1–4nm using flour as the carbon source. It suggests that the resultant C-dots exhibit high sensitivity and selectivity toward Hg2+ with a detection limit as low as 0.5nM and a linear range of 0.0005–0.01μM. The practical use of this system for Hg2+ determination in real lake water samples is also demonstrated successfully. [Copyright &y& Elsevier]

Abstract: The present communication reports on the first preparation of porous tubular C/MoS2 nanocomposites using porous anodic aluminum oxide as a template. We further demonstrate the application of such composites as a novel electrode material for supercapacitors. It is found that they can deliver a high capacitance of 210F/g at 1A/g and exhibit excellent long-term cycling stability over 1000 cycles. [Copyright &y& Elsevier]

Abstract: The carbon nitride dots (CNDs) can serve as an effective stabilizing agent for reduced graphene oxide (GO) prepared by chemical reduction using hydrazine hydrate as the reducing agent. Physicochemical characterization with a combination of techniques including UV–vis spectroscopy, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy indicate the preparation of aqueous dispersion of rGO and the formation of CNDs–rGO hybrids. We further demonstrate the subsequent self-assembly of the CNDs–rGO with glucose oxidase (GOD) into hybrids, which is confirmed by the scanning electron microscopy and electron energy dispersive spectrum analysis. As a typical application of such materials, a glucose biosensor has been constructed by deposition of the GOD–CNDs–rGO hybrids on the surface of a glassy carbon electrode. The linear detection range and detection limit are estimated to be from 40μM to 20mM (r =0.994) and 40μM at signal-to-noise ratio of 3, respectively. It is further shown that this glucose biosensor can be used for glucose detection in human blood serum. [Copyright &y& Elsevier]

Abstract: The present communication reports on the preparation of WS2 nanoparticles–encapsulated amorphous carbon tubes (WS2NPs/CTs) via two-step processes. Firstly, CTs were grown in anodic aluminum oxide (AAO) film by hydrothermal carbonization of glucose. Secondly, the as-prepared CTs/AAO film was impregnated with (NH4)2WS4 followed by high temperature treatment in Ar atmosphere. We further demonstrate the application of the resulting WS2NP/CT composites as a novel electrode material for supercapacitor. Such composites were found to deliver a specific capacitance of 337F/g at a high current density of 10A/g with good cycle stability. [Copyright &y& Elsevier]

Abstract: In this paper, we report on one-pot synthesis of Ag nanoparticles/reduced graphene oxide (AgNPs/rGO) nanocomposites by heating mixed solution of graphene oxide (GO) and AgNO3 with the use of diethylenetriamine as a reducing agent at 80°C for 30min. Several analytical techniques including UV–vis spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM) have been employed to characterize the resulting nanocomposites. It was found that such nanocomposites exhibit good catalytic activity toward the reduction of H2O2. This nonenzymatic H2O2 sensor shows a fast amperometric response time of less than 2s. The linear detection range is estimated to be from 0.1 to 100mM (r =0.999), and the detection limit is estimated to be 3.6μM at a signal-to-noise ratio of 3. [Copyright &y& Elsevier]

Abstract: Low-dimensional nanoparticles composed SnO2–Co3O4 nanocubes (NCs) were prepared by a hydrothermal method using reducing agents. The doped nanomaterials were investigated by UV/vis, powder X-ray diffraction, FT-IR, energy-dispersive X-ray spectroscopy (EDS), and Raman spectroscopy, and field-emission scanning electron microscopy. They were deposited on a silver electrode (AgE, surface area, 0.0216cm2) to give a drug sensor with a fast response towards Olmesartan medoxomil (OSM) in 0.1molL−1 phosphate buffer-phases. The sensor also exhibits higher sensitivity, long-term stability, and enhanced electrochemical response. The calibration plot is linear (r 2=0.9948) over the 0.28nmolL−1–1.4μM OSM concentration range. The sensitivity is ∼2.083μAcm−2 mmolL−1 and the detection limit is 0.17nmolL−1 (at an SNR of 3). We discuss the possible potential uses of this nanoparticles doped semiconductor NCs in terms of drug sensing, which could also be employed for the determination of drugs in quality control of formulation. [Copyright &y& Elsevier]

Abstract: Ag nanoparticles-decorated reduced graphene oxide (AgNPs-rGO) has been successfully fabricated through a one-step strategy, carried out by hydrothermal treatment of the mixture of AgNO3 and GO solution under strong alkaline conditions at 180°C for 30min. The reaction was accomplished without extra reducing agent and surface modifier. As-synthesized AgNPs-rGO has been successfully applied in catalytic performance toward the reduction of H2O2. This H2O2 sensor shows a wide linear range of 0.1–60mM (r =0.991) and a low detection limit of 1.80μM at a signal-to-noise ratio of 3. [Copyright &y& Elsevier]

Abstract: The present communication reports a novel and simple strategy to synthesize Au nanoplates (AuPs) by heating an aqueous solution of HAuCl4 in the presence of poly [(2-ethyldimethylammonioethyl methacrylate ethyl sulfate)-co-(1-vinylpyrrolidone)] (PQ11). Direct placing of the resultant dispersion on a glassy carbon electrode (GCE) surface gives a very stable AuPs-containing film exhibiting remarkable catalytic performance toward both the oxidation and reduction of H2O2. This enzymeless H2O2 sensor shows a fast amperometric response time of less than 3s and the corresponding linear range and detection limit are estimated to be from 0.1mM to 50mM (r =0.999) and 4μM at a signal-to-noise ratio of 3, respectively. [Copyright &y& Elsevier]

Abstract: We report the effects of polar-protic and polar-aprotic solvents on absorption spectra and particle size of surfactant stabilized silver nanoparticles. Cysteine and cetylteimethylammonium bromide, CTAB were used as the reducing and stabilizing agents, respectively. The prepared orange color silver sols possess an unusually narrow Plasmon absorption shoulder at 450nm. The absorbance and shape of this shoulder are affected by protic (methanol, ethanol) and aprotic (acetonitrile, DMF, DMSO and 1,4-dioxane) solvents. The observed results are interpreted in terms of the dielectric constant, boiling point, hydrogen bonding, solubilization and donation of electron density from the silver particles to the solvents. Absorbance increases with increasing the dielectric constants of reaction mixture. The particle size decreases with decreasing the hydrophobic character of protic solvents: particle size=70, 58 and 39nm in presence and absence of solvents (ethanol and methanol), respectively. [Copyright &y& Elsevier]