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[Display omitted] • SnS 2 flakes/CdS rods nanocomposite was synthesized by a two-step hydrothermal method. • Glutathione was introduced as both a structural guide and a hole absorber. • SnS 2 /CdS/GSH had optimal photocathode protection effect compared with SnS 2 /CdS. • The OCP of 304 SS coupled with SnS 2 /CdS/GSH decreased by 320 m V after light. An effective way to enhance photochemical performance can be achieved by optimizing the microstructure of composite semiconductor materials. Here, a two-step hydrothermal method was used to synthesize SnS 2 /CdS composite photoanodes for photocathode protection applications, and glutathione was introduced as a structure-directing agent to enhance the separation efficiency of photogenerated electron-hole pair of SnS 2 /CdS. In the presence of glutathione, SnS 2 became a smaller and thinner nanoflake and hexagonal CdS extended into a rod shape, the combination of them resulted in larger light collection area and higher charge transfer rate. The electrochemical test results demonstrated that the open circuit potential of 304 SS coupled with SnS 2 /CdS/GSH photoanode was negatively shifted to about −0.5 V under light, which not only far exceeded the self-corrosion potential of 304 SS (-0.18 V), but also improved from −0.42 V of SnS 2 /CdS. Further, the photogenerated current density of SnS 2 /CdS/GSH was nearly three times that of SnS 2 /CdS, EIS and polarization curve results also indicated that glutathione enhances the PEC performance of SnS 2 /CdS. Obviously, the type-II heterojunction formed by glutathione-sensitized SnS 2 /CdS provides more electrons for 304 SS, which is beneficial to achieve better photocathodic protection. [ABSTRACT FROM AUTHOR]

• Cu/Cr bilayer films were deposited onto diamond to simulate actual interface in Cu/diamond composites. • The h between Cu and diamond was measured by a time-domain thermoreflectance technique. • The Cu/Cr/Cr 3 C 2 /diamond structure with a mixed Cr and Cr 3 C 2 interlayer exhibits the maximum h value of 168 MW/m2 K. • This study provides guideline for interface modification to attain high thermal conductivity in Cu/diamond composites. Interfacial thermal conductance (h) plays a decisive role in attaining high thermal conductivity in diamond particles reinforced Cu matrix (Cu/diamond) composites for promising thermal management applications. In this article, Cu/Cr bilayer films were deposited onto a single-crystalline diamond substrate by magnetron sputtering to form a Cu/Cr/diamond sandwich structure to clarify the role of the Cr interlayer in determining h between Cu and diamond. The 50 nm-thick Cr film was deposited at 773 K with various lengths of holding time to regulate the transformation of Cr to Cr 3 C 2. The h between Cu and diamond was experimentally measured by a time-domain thermoreflectance technique. The Cu/Cr/Cr 3 C 2 /diamond structure with a mixed Cr and Cr 3 C 2 interlayer exhibits an h value of 168 MW/m2 K, higher than 57 MW/m2 K for the Cu/diamond structure, 96 MW/m2 K for the Cu/Cr/diamond structure, and 86 MW/m2 K for the Cu/Cr 3 C 2 /diamond structure. The Cr interlayer improves the interfacial bonding and reduces the acoustic impedance mismatch between Cu and diamond; however, the full transformation of Cr to Cr 3 C 2 reduces the h value due to lower thermal conductivity of Cr 3 C 2 than Cr. This study provides guideline for interface modification to attain high thermal conductivity in Cu/diamond composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Dual oxide co-decorated necklace-like CNF (TiO 2 @SiO 2 /CNF) flexible electrocatalytic membrane interlayer was prepared. • The necklace-like structure enhances structural stability and provides more active sites. • The TiO 2 @SiO 2 /CNF synergistically combined the advantages of high conductivity and high electrocatalytic activity. • The Li-S batteries with TiO 2 @SiO 2 /CNF interlayer achieve outstanding rate performance and cycling stability. Lithium-sulfur (Li-S) batteries are regarded as new energy storage systems due to their low cost and high specific energy density; however, their commercial prospects are hindered by the shuttle effect of lithium polysulfides (LiPSs). Herein, the fabricating necklace-like carbon nanofibers membrane co-decorated by TiO 2 and SiO 2 (TiO 2 @SiO 2 /CNF) is prepared by the electrospinning technique as an interlayer to catalyze the conversion of LiPSs in Li-S batteries. The necklace-like nanofibers provide a three-dimensional conductive network, enabling SiO 2 synergy with TiO 2 to accelerate the redox kinetics of LiPSs through an enhanced interfacial effect. The Li-S batteries based on TiO 2 @SiO 2 /CNF interlayers exhibit an impressive specific capacity of 658 mAh g−1 at 3.0C, and their performances are decayed only 0.05 % per cycle at 1.0C within 500cycles. Our study reveals that the shuttle effect addition of LiPSs can be significantly improved by rational structural design, thus enhancing the electrochemical performance of Li-S batteries. The synthesis of necklace-like TiO 2 @SiO 2 /CNF presents a promising strategy for designing functional interlayers for advanced Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon-decorated hollow TiN architecture is synthesized through a facile hydrothermal-calcination strategy. • Carbon is employed to tunable the surface state and composition of three-dimensional TiN. • The state-of-art H-TiN/NC-1.00 exhibits superior both electrocatalytic activity and durability towards ORR. • High performance benefits from its synergistic effect between unique hollow nanostructure and multiple active sites. The development of low-cost and high-efficient electrocatalysts for oxygen reduction reaction (ORR) is a severe challenge for the commercial application of fuel cells. Herein, a durable acidic ORR electrocatalyst composed of carbon nanoparticles decorated on a mesoporous structure of TiN hollow spheres (H-TiN/NC-x) is fabricated for the first time through a hydrothermal-calcination strategy. By moderately adjusting carbon content, the H-TiN/NC-1.00 catalyst exhibits remarkable ORR performance in 0.1 M HClO 4 electrolyte with a half-wave potential of 0.80 V, which is close to commercial Pt/C catalyst (0.83 V). Meanwhile, the catalyst reveals a high selectivity for the four-electron pathway with lower H 2 O 2 yield (7 %) and superior tolerance ability to methanol crossover. More importantly, the H-TiN/NC-1.00 catalyst exhibits a higher stability with negligible activity decay than Pt/C catalyst (ΔE 1/2 = −80 mV) after 10,000 potential cycles. This outstanding ORR performance for H-TiN/NC-1.00 is attributed to the synergistic effect of unique hollow nanostructure and multiple active sites, which can improve electron transfer and ion diffusion/penetration, maintain the structural stability of hollow spheres for exposing more active sites (H-TiN and NC). Our work demonstrates that manipulating surface state and composition of TiN material is a superior method for optimizing ORR performance in fuel cells applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow CoSe 2 nanospheres are wrapped with flexible rGO nanosheets. • rGO on hollow CoSe 2 nanospheres reduces their aggregation and nanoparticle size. • OH– is more easily adsorbed at the CoSe 2 /rGO interface. • Hollow CoSe 2 /rGO electrodes exhibit enhanced rate capacities and cyclic stability. In this work, hollow CoSe 2 nanospheres wrapped with reduced graphene oxide (rGO) nanosheets are fabricated through combining the self-templated method with the electrostatic self-assembled method followed by heat treatment. The experimental results indicate that rGO nanosheets can act as space separator and structural protector to reduce the aggregation and nanoparticle size of hollow CoSe 2 nanospheres and meanwhile maintain their structural integrity. Density functional theory calculations indicate that the wrapping of rGO nanosheets not only increases the electrical conductivity but also reduces the adsorption energy of OH– at the CoSe 2 /rGO interface. Accordingly, hollow CoSe 2 /rGO nanocomposites yield specific capacities of 757C g−1 at 3 A/g and 552C g−1 at 20 A/g, as well as a capacity retention of 92 % over 5000 cycles at 10 A/g. When coupled with N -doped carbon nanotube-based negative electrode, the fabricated HSC device delivers an energy density of 50.1 W h kg−1 at 800 W kg−1 as well as maintains a capacity retention of 94 % after 5000 cycles. Our work offers a further understanding of the charge storage mechanism of hollow CoSe 2 /rGO nanocomposites and may be extended to develop other advanced nanostructured metal selenides/graphene electrodes. [ABSTRACT FROM AUTHOR]

Electrospun poly( l -lactic acid) (PLLA) nanofiber mats were successfully modified by deposition of multilayers with chitosan (CS), heparin (Hep) and graphene oxide (GO) through electrostatic layer-by-layer (LBL) self-assembly method. In this study, the surface properties of PLLA nanofiber mats before and after modification were investigated via scanning electron microscope (SEM), atomic force microscopy (AFM), attenuated total reflectance fourier transformation infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. In addition, the cytocompatibility of the modified PLLA nanofiber mats were investigated by testing endothelial cells compatibility, including cell attachment, cell proliferation and cell cycle. The results revealed that the surfaces of modified PLLA nanofiber mats become much rougher, stifiness and the hydrophilicity of the LBL modified PLLA nanofiber mats were improved compared to original PLLA one. Moreover, the modified PLLA nanofiber mats had promoted the endothelial cells viability attachment significantly. Besides, we studied the PLLA nanofiber mats on the expression of necrosis factor (TNF-α), interleukine-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells. The results showed that modified PLLA nanofiber mats had inhibited the inflammatory response to some extent. [ABSTRACT FROM AUTHOR]

BiVO 4 film coupled with resorcinol–formaldehyde resin (RFS) nanoparticles to form BiVO 4 /RFS heterojunction film as photoanode for solar water oxidation. The conduction and valence band potential of RFS nanoparticles were lower than those of BiVO 4 , and the surface holes and electrons could be directionally transferred to RFS nanoparticles and BiVO4 film, respectively. [Display omitted] • BiVO 4 /RFS film photoanodes were prepared by coupling BiVO 4 films with resorcinol–formaldehyde resin nanoparticles for solar water oxidation. • The light harvesting and electrochemical properties of the optimal BiVO 4 /RFS film was close to the BiVO 4 film. • Better water oxidation activity, kinetics and stability were observed on the BiVO 4 /RFS film photoanode. • The conduction and valence band potential of RFS nanoparticles were lower than those of BiVO 4 , and their surface holes and electrons could be directionally transferred to RFS nanoparticles and BiVO 4 film, respectively. The poor properties of carrier separation and transfer on BiVO 4 surface are two major bottlenecks for nanostructured BiVO 4 photoanodes during solar water oxidation. Herein, BiVO 4 /resorcinol–formaldehyde resin (BiVO 4 /RFS) heterojunction films were prepared by coupling resorcinol–formaldehyde resin (RFS) nanoparticles on BiVO 4 films' surface, and investigated as photoanodes for solar water oxidation. The light harvesting and electrochemical properties of the resultant BiVO 4 /RFS film was close to the BiVO 4 film, but its carrier radiative recombination was weakened significantly. Relative to the BiVO 4 film photoanode, better water oxidation activity, kinetics and stability were observed on the BiVO 4 /RFS film photoanode. The conduction and valence band potential of RFS nanoparticles were discovered to be lower than those of BiVO 4 , and the surface photogenerated holes and electrons could be directionally transferred to RFS nanoparticles and BiVO 4 film, respectively. The higher solar water oxidation performance on the BiVO 4 /RFS photoanode was mainly originated from the separation and transfer of surface carrier through the BiVO 4 /RFS coupling interfaces under AM 1.5G irradiation. The present work could provide inspiration in the design and development of similar heterojunction materials for solar water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1. W doped 1T MoS 2 has been synthesized via hydrothermal. • 2. W doped into 1T MoS 2 causes electrons redistribution on the surface. • 3. W-1T MoS 2 -15 demonstrated the excellent HER activity and stability. • 4. DFT calculations demonstrated that W doped 1T MoS 2 could reduce the ΔG H*. The intrinsic electronic structure on the surface of 1T MoS 2 makes the non-optimal bonding strength with hydrogen atoms, which is the key factor that the catalytic performance cannot be improved. However, modifying surface electronic structure by doped exotic atom is an effective approach to optimal the bonding strength between hydrogen atoms and 1T MoS 2. Herein, this work reports W doped 1T MoS 2 with different concentrations by hydrothermal method. The results indicate that W-1T MoS 2 -15 exhibits excellent catalytic activity for hydrogen evolution reaction (HER), the catalytic activity is better than that of 2H MoS 2 and pristine 1T MoS 2 , the lowest overpotential and tafel slope in acid electrolyte is 292 mV and 55.7 mV dec−1, respectively. Theoretical calculation results show that W-1T MoS 2 -2/9 has relatively much lower barrier than pristine 1T MoS 2 both in Volmer reaction and Heyrovsky reaction. Therefore, W-1T MoS 2 -2/9 has a faster reaction kinetics for HER. In addition, introducing W atoms can trigger spontaneous electrons redistribution on the basal plane, optimize energy level, and reduce the Gibbs free energy. This study confirmed that doping of atom with similar physical and chemical properties can optimize electronic structure of 1T MoS 2 on the basal plane, and effectively improve its electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The novel magnetically recyclable direct Z-scheme Cd x Zn 1-x S-FG nanocomposites were synthesized by a simple hydrothermal method, which displayed the excellent photocatalytic hydrogen evolution and photocatalytic degradation activity under visible light irradiation. [Display omitted] • The Cd x Zn 1-x S-FG multifunctional photocatalysts were successfully synthesized by a simple hydrothermal method. • The photocatalytic hydrogen evolution and photocatalytic degradation properties of the samples were investigated under visible light irradiations. • The direct Z-scheme transfer of electron-hole pairs was confirmed in Cd x Zn 1-x S-FG nanocomposites. • An easy magnetically separable and recoverable process was achieved. In this paper, we reported a simple hydrothermal strategy to prepare the direct Z-scheme Cd x Zn 1-x S nanorods-Fe 2 O 3 quantum dots heterojunction/reduced graphene oxide (Cd x Zn 1-x S-FG) nanocomposites as the multifunctional photocatalysts for photocatalytic degradation of organic dyes and photocatalytic hydrogen evolution. By adjusting the molar mass ratio of Cd2+ and Zn2+ ions from 9:1 to 1:9, the bandgap of the Cd x Zn 1-x S-FG nanocomposites can be turned from 2.23 to 3.49 eV. The Cd 0.3 Zn 0.7 S-FG nanocomposites exhibited the highest H 2 evolution rate of 26.8 mmol h−1 g−1 and the highest degradation efficiency of 97.32% towards MB in 120 min under the visible light irradiation. The excellent photocatalytic activity can be attributed to the high-efficiency transportation and separation of the photogenerated electron-hole pairs, more catalytic active sites and large specific surface area. The mechanism of the photocatalytic hydrogen evolution and photocatalytic degradation had been investigated by ultraviolet photoelectron spectroscopy, scavenging experiment, and UV–Vis absorption spectra. Considering the unique structure, morphology, and excellent photocatalytic performances of the Cd x Zn 1-x S-FG nanocomposites, it will become a burning star in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

Abstract: ZnO quantum-dot chains codoped with Eu3+ and Er3+ were synthesized by the chemical precipitation method and the codoping effects on the structures, morphologies and optical properties of the powders were briefly investigated. The X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) results indicated the Eu3+ and Er3+ were incorporated into the crystal lattice of ZnO host. Transmission electron microscope (TEM) measurements showed the sizes of the ZnO quantum dots decreased with the increase of Eu3+ and Er3+ doping concentration, and the quantum-dot chains were formed by codoping with Eu3+ and Er3+. The green emissions in the photoluminescence spectra were attributed to 4f–4f of Er3+ inner shell 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions, and the characteristic red emissions of Eu3+ ions were attributed to the 5D0 → 7F1 and 5D0 → 7F2 transitions, respectively. Moreover, the red emission of the Eu3+ ions gradually decreased with the Er3+ ions doping concentration increased, which may be due to the different energy storage centers in the powders. [Copyright &y& Elsevier]

Abstract: Mn-doped ZnO nanorods were synthesized from aqueous solutions of zinc nitrate hexahydrate, manganese nitrate and methenamine by the chemical solution deposition method (CBD). Their microstructures, morphologies and optical properties were studied in detail. X-ray diffraction (XRD) results illustrated that all the diffraction peaks can be indexed to ZnO with the hexagonal wurtzite structure. Scanning electron microscope (SEM) results showed that the average diameter of Mn-doped ZnO nanorods was larger than that of the undoped one. Photoluminescence (PL) spectra indicated that manganese doping suppressed the emission intensity and caused the blue shift of UV emission position compared with the undoped ZnO nanorods. In the Raman spectrum of Mn-doped ZnO nanorods, an additional mode at about 525cm−1 appeared which was significantly enhanced and broadened with the increase of Mn doping concentration. [Copyright &y& Elsevier]

Abstract: Zinc oxide (ZnO) nanorods were grown on three kinds of substrates (Si, glass and ITO-conducting glass) by the chemical solution deposition method (CBD) in an aqueous solution that contained zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and methenamine (C6H12N4). The nature of the substrate was found to have effect on the crystal structure, morphologies and photoluminescence properties of the resultant ZnO nanorods. From the X-ray measurement results, it can be seen that the growth orientation of the resultant ZnO nanorods deposited on various substrates were (002), but the highest intensity of (002) diffraction peak appeared in the samples deposited on glass and ITO-conducting glass compared to that of Si substrate. SEM results showed the nanorods grown on the bare glass had the most uniform size and the highest coverage density. Photoluminescence measurements were also carried out, the result showed that the ZnO nanorods grown on three kinds of substrates had different photoluminescence behaviors, and the one grown on the Si substrate had the best performance. And the small shift in the UV emission was caused by the compressive stress from the Raman measurement results. [Copyright &y& Elsevier]

[Display omitted] • SrFe 12 O 19 /MoS 2 heterojunction composite are synthesized via hydrothermal method. • The exposed interface reduce the recombination rate of the photogenerated carrier. • The composite achieved high degradation rate with magnetic recovery ability. Photocatalysis is one of the most promising technologies in wastewater treatment. Efficient degradation under visible light and the recovery capability of the photocatalyst are crucial in real-word applications. Herein, M−type SrFe 12 O 19 was integrated into the surface of flowerlike MoS 2 microsphere via the hydrothermal method. As-prepared SrFe 12 O 19 /MoS 2 composite photocatalyst has effective visible light response and magnetic recovery ability. The SrFe 12 O 19 /MoS 2 composite achieved 97% degradation rate for methylene blue under visible light. The photocatalytic reaction rate of the SrFe 12 O 19 /MoS 2 composite was nearly twice that of pure MoS 2. Transient steady-state fluorescence spectrometry and electrochemical spectrometry revealed that an appropriate amount of SrFe 12 O 19 effectively improves the charge transfer rate and accelerates photoinduced charge carrier separation. The possible photocatalytic degradation mechanism of the SrFe 12 O 19 /MoS 2 composite with the p–n heterojunction was also examined. [ABSTRACT FROM AUTHOR]

Abstract: Mg-doped Ni nanoparticles with the hexagonal close-packed (hcp) and face-centered cubic (fcc) structure have been synthesized by sol–gel method sintered at different temperatures in argon atmosphere. The sintering temperature played an important role in the control of the crystalline phase and the particle size. The pure hcp Mg-doped Ni nanoparticles with average particle size of 6.0nm were obtained at 320°C. The results indicated that the transition from the hcp to the fcc phase occurred in the temperature range between 320°C and 450°C. Moreover, the VSM results showed that the hcp Mg-doped Ni nanoparticles had unique ferromagnetic and superparamagnetic behavior. The unsaturation even at 5000Oe is one of the superparamagnetic characteristics due to the small particle size. From the ZFC and FC curves, the blocking temperature T B of the hcp sample (6.0nm) was estimated to be 10K. The blocking temperature was related to the size of the magnetic particles and the magnetocrystalline anisotropy constant. By theoretical calculation, the deduced particle size was 6.59nm for hcp Mg-doped Ni nanoparticles which was in agreement with the results of XRD and TEM. [Copyright &y& Elsevier]

The novel magnetically recyclable direct Z-scheme GZxFy nanocomposites were synthesized by a simple hydrothermal method, which displayed the excellent photocatalytic activity under UV and visible light irradiation. • The GZxFy nanocomposites photocatalysts were successfully synthesized by a simple hydrothermal method. • The photocatalytic properties of the samples were investigated under UV and visible light irradiations. • The direct Z-scheme transfer of electron-hole pairs was confirmed in GZxFy nanocomposites. • An easy magnetically separable and recoverable process was achieved. A novel direct Z-scheme ZnS quantum dot (QD)-Fe 2 O 3 QD heterojunction/reduced graphene oxide (rGO) (GZxFy) nanocomposite was successfully synthesized by a simple hydrothermal method. The surface of ZnS and Fe 2 O 3 QDs was modified by COOH and OH groups, respectively. ZnS QDs can be covalently bonded with Fe 2 O 3 QDs by the dehydration reaction to form the ZnS QDs-Fe 2 O 3 QDs heterojunctions. The GZxFy nanocomposites displayed the highest photodegradation efficiency of 96.45% (40 min, UV light) and 90.17% (480 min, visible light) for methylene blue when the mass ratio of ZnS QDs to Fe 2 O 3 QDs was 1:3. The excellent photocatalytic activity could be attributed to the enhanced light-harvesting ability, high large specific surface area, efficient interfacial charge-carrier separation and transfer as well as the low charge transfer resistance. Ultraviolet photoelectron spectroscopy and radical trapping experiments were used to confirm the Z-scheme mechanism formed between ZnS QDs and Fe 2 O 3 QDs, and verify the electron transfer direction for UV or visible light-driven photocatalytic reactions. GZ1F3 nanocomposites showed the excellent superparamagnetic behavior, which enabled its rapid magnetic recycle from the solution within 95 s in a magnetic field. [ABSTRACT FROM AUTHOR]