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[Display omitted] • A novel photocatalyst (D-cys/Au NPs-TiO 2 , DAT) was successfully fabricated. • The highest degradation rate of DAT for chlorpyrifos reaches 96.7%. • The degradation pathway of OPPs involved oxidation of P = S, cleavage of O-P and C-O. • This study provides a potential approach to remove OPPs in fruits and vegetables. The widespread use of organophosphorus pesticides (OPPs) in foods, poses a serious threat to human and environmental health, it is crucial to develop methods that can efficiently degrade residual OPPs. Herein, a chiral TiO 2 photocatalyst was developed by modification TiO 2 with D-cys/Au NPs (DAT) for the simultaneous degradation of four OPPs (chlorpyrifos, chlorpyrifos-methyl, malathion, and parathion) by natural light. The influence of D-Au NPs concentration on the degradation process was optimized, along with the initial pesticide concentration. Under optimal conditions, the photocatalytic degradation efficiencies of DAT for four OPPs were 96.7 %, 56.9 %, 42.6 %, and 49.2 %, respectively, after 12 h of natural light exposure. 12 degradation products of OPPs were identified, among which three products were identified for the first time. The degradation pathway revealed that the degradation of OPPs by DAT involves the oxidation of the P═S bond and the cleavage of the P-O bond and C-O bond. This study establishes a theoretical foundation for applying chiral TiO 2 nanomaterials for the photocatalytic degradation of OPPs in foods. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The combination of gold nanostars with three-dimensional opal photonic crystals was applied to SERS trace detection. • The faster detection time and lower detection limits were obtained. • The local electromagnetic field distribution for the photonic crystals and AuNS composite substrates were calculated. Abstract The efficient extraction of targets from complex environment is the key to analyze explosive traces and soil pollution. In recent years, the focus of Raman detection of trace organic pollutants is to create hotspots for amplifying Raman signals. This paper demonstrated the combination of gold nanostars (AuNS) fabricated by seed mediated growth method with three-dimensional opal photonic crystals for SERS trace detection. As a result, the obtained composite structures show excellent SERS activity with low detection limits of 540 ppt to 3-Phenoxybenzoic acid (3-PBA) (0.54 ppb) and fast detection time of 10 s. The utility of the composite structures was demonstrated by directly detecting soil pollution in water with a simple dropping. Additionally, the local electromagnetic field distribution for the photonic crystals and AuNS composite substrates were calculated by the finite difference time domain (FDTD) method. Overall, this work provides a simple, rapid, and sensitive way to monitor the insecticides in the soil and other side. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Polypyrrole (PPy) was hydrogen bonded with plasma-treated carbon fiber (PCF). • PCF/PPy composite electrode was designed from the relationship of interfacial interaction-electrochemical performance. • The interfacial hydrogen bond enhanced the electrochemical stability of PCF/PPy. Abstract The design of a strong interface interaction is a critical issue to improve the electrochemical stability of polypyrrole (PPy) composite electrodes. In the natural world, hydrogen bond that powers the load transfer can be observed in spider silk. The challenges are to achieve interfacial hydrogen bond interaction to stiff the PPy to help the effective load transfer and alleviate the swelling/shrinkage of PPy chains. Here, a composite electrode was prepared by pyrrole (Py) vapor deposition on the air-plasma-activated carbon fabric (PCF) surface. The X-ray photoelectron spectroscopy and fourier transformed infrared spectroscopy results showed that the COOH groups appearing on the PCF and hydrogen bonds can be formed on the interface of PCF/PPy. Interfacial shear strength (IFSS) and scanning electronic microscope determined hydrogen bond on the interface of PCF/PPy enhance the adhesion and power the load transfer process from PPy to carbon fiber. These interfacial hydrogen bonds severed as adhesion points helped the load transfer effectively to the substrate and decreased the contact resistance, preventing the damage of PPy chains and improving electrochemical performances of PCF/PPy as the electrode for pseudosupercapacitor. The PCF/PPy supercapacitor showed excellent cycling stability (93% capacitance retention after 4000 cycles), while CF/PPy showed poor cycling stability (74% after 4000 cycles). The idea of hydrogen bond powered electrochemical stability can be of reference for the researchers to improve the cycling stability of other conductive polymers that are widely used in high-performance supercapacitor. [ABSTRACT FROM AUTHOR]

The Cu/TiO 2 /organo-attapulgite fiber (CTOA) nanocomposite was synthesized by a facile method and was used for photocatalytic degradation of acetone in air under UV light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectrum (UV–vis DRS), inductively coupled plasma (ICP) spectrometry and N 2 adsorption–desorption measurement. The results showed that the structure of organo-attapulgite (OAT) had no obvious change as compared to unmodified attapulgite (AT) and the attapulgite fibers in the OAT were well-dispersed. Both micropores and mesopores exist in the CTOA catalyst. The CTOA catalysts prepared at the Cu/TiO 2 molar ratio of 0.003 shows an excellent photocatalytic activity for the degradation of acetone in air. The synergistic effect of Cu species and cetyltrimethylammonium bromide modification can be responsible for the enhanced photocatalytic activity of the CTOA catalyst. The mechanism of the photocatalytic degradation of acetone by the CTOA catalyst was discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanoscale frictional properties of three TMD monolayers: WSe 2 experiences the lowest friction. • Friction on monolayers is not dependent on sliding speed. • TMD monolayers successfully prevent probe wear up to 10 μN load. We present nanoscale frictional analysis of three commonly used transition metal dichalcogenide (TMD) monolayers, WS 2 , MoSe 2 and WSe 2 , deposited by chemical vapour deposition (CVD). The monolayers were characterised by Raman spectroscopy, photoluminescence spectroscopy (PL), and X-ray spectroscopy (XPS), to determine the composition of the coating and confirm monolayer structure. Nanoscale frictional analysis was performed by atomic force microscopy (AFM). Load-dependent frictional behaviour was measured at different sliding speeds to quantitatively assess friction on each sample. All samples experienced low nanoscale friction, with the lowest friction observed on WSe 2. The friction was independent of sliding speed within the analysed range. Furthermore, monolayer TMDs significantly increase the operational load range by at least one order of magnitude when compared to SiO 2 substrate. [ABSTRACT FROM AUTHOR]

• Novel direct 2D/2D Z-scheme SnNb 2 O 6 /ZnO hybrid photocatalyst was synthesized. • SnNb 2 O 6 /ZnO shows excellent photocatalytic activity for RhB and phenol degradation. • The composite exhibits broader light absorption and facilitated charge separation. • This work provides a novel insight for other 2D/2D Z-scheme heterojunction. The development of high-efficiency heterostructure photocatalysts is an attractive strategy for aquatic pollutants degradation. Herein, a novel 2D/2D Z-scheme heterojunction between SnNb 2 O 6 nanosheets and flower-shaped ZnO nanosheets was designed and fabricated through a simple two-step hydrothermal method. As expected, the obtained composite photocatalyst exhibits outstanding photodegradation efficiencies for RhB and phenol. The optimal reaction rate constant over 20%-SnNb 2 O 6 /ZnO heterostructure in RhB degradation is almost 15.03 and 3.95 times higher than pristine SnNb 2 O 6 and ZnO, respectively. Such an improved photocatalytic activity is mainly ascribed to the broader optical absorption and facilitated charge separation, which can be proved by various analytical methods. This designed composite also displayed excellent stability in four-cycle experiments. Additionally, a possible direct Z-scheme electron migration mechanism under an internal electric field was proposed with the aid of reactive species trapping experiments. This work provides a feasible strategy to obtain high-performance photocatalysts and might inspire a new perspective in the design of other 2D/2D Z-scheme heterojunctions for environmental purification. [ABSTRACT FROM AUTHOR]

Fabrics with spontaneous one-way water transport property have received much attention in scientific and industrial communities in the recent years. However, limited knowledge is available about how to control and adjust directional water transport capacity on fabrics. In this study, we have prepared one-way water transport fabrics using three plain-woven cotton fabrics, which have different pore sizes, as substrates. An electrospray technique was employed to deposit hydrophobic coating on one side of the fabrics. One-way water transport property was attained when the coating thickness was in the range of 9.0–23.9 μm. The fabric pore size was found to be a critical factor deciding the maximum one-way water transport capacity that can be achieved on the fabric. With the same coating thickness, the fabric with smaller pores showed larger one-way transport capacity. These novel results may be useful for designing high performance one-way water transport fabrics for various applications. [ABSTRACT FROM AUTHOR]

Abstract: 2,6-Di-t-butyl-p-hydroxytoluene (BHT), a common antioxidant, has been implicated in oil foods and food packaging materials as a substance that could migrate into the food supply chain and cause suppression of human respiratory enzymes. In this study, BHT solutions in different solvents were measured by surface enhanced Raman spectroscopy (SERS) in combination with SERS-active substrates: gold colloidal nanoparticles. The limit of detection of BHT can reach the level of 10μg/mL with SERS in methanol. The Raman peak at 766cm−1 was used as the index of quantitative analysis and the correlation coefficient was 0.9761. These results demonstrated the applicability of utilizing SERS to detect low concentrations of BHT. By comparing the features of SERS peaks with the density functional theory (DFT)-calculated Raman spectrum, the adsorption behavior of BHT on the surface of gold nanoparticles was analyzed in detail and it was determined that the dominant contribution to the SERS signal in this case should be the electromagnetic enhancement mechanism. A charge-transfer mechanism also contributed to the SERS signal for BHT adsorbed on gold nanoparticles by the Phce:hsp sp="0.25" />=phenyl) coalescent format. [Copyright &y& Elsevier]

Diamond films were deposited on cobalt-cemented tungsten carbide (WC-Co) by Hot-Filament Chemical Vapor Deposition (HFCVD). The mechanical properties and wear behavior of single-layer and multi-layer diamond films were compared, based on the difference of diamond crystal formation and internal structure. Adhesive failure modes and critical loads, post-scratch tests, were identified according to the applied load, acoustic emission and friction force. For single-layer diamond films, the samples produced with lower CH 4 concentration evidence columnar crystal diamond structure, which exhibit better adhesive properties. The samples produced with 5% CH 4 exhibit the lowest hardness, however, due to their higher crystallinity and nucleation density, they exhibit higher toughness. The multi-layer diamond film with 300 nm alternate thickness per interlayer shows the highest critical delamination load (23.22 N). Concerning the multi-layer diamond films, the hardness and Young's modulus increases from 84.13 to 94.01 GPa and 788.65 to 936.26 GPa, respectively, with the alternate thickness change from 100 nm to 600 nm per layer, which indicates that thicker alternate layers lead to higher hardness and toughness. The wear behavior of the nano-crystalline (NCD) single-layer diamond films is potentially related to the less adequate adhesive abilities to the substrate material. • Single and multi-layer diamond films with alternate micro-nano crystalline structures were prepared by HFCVD. • The single-layer microcrystalline films exhibited high critical loads of adhesive failure. • The micro-nano alternate thickness of 300 nm per layer exhibit the highest critical adhesion load. • The multi-layer structures exhibit an enhancement on the adhesion properties, and hardness and Young's modulus. [ABSTRACT FROM AUTHOR]