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• Composite catalyst was constructed by Ni-MOF and Al 2 O 3. • Addition Al 2 O 3 solves the Ni agglomeration caused by Ni-MOF decomposition. • Ni/NA-MOF-450 exhibits excellent hydrogenation performance for benzene. Metal-organic frameworks (MOFs) is easy to agglomerate at high temperature, resulting in the rapid collapse of the MOFs structure and the aggregation of metal sites. In this paper, Al 2 O 3 is used as the support material to support the in-situ synthesis of Ni-MOF on the surface, and the metal Ni nanoparticles are successfully fixed on the Al 2 O 3. The results showed that both Ni/Ni-MOF-300 and Ni/NA-MOF-300 catalysts reduced at 300 ℃ have good hydrogenation activity of benzene, and Ni/Ni-MOF-450 catalysts reduced at 450 ℃ formed huge Ni aggregates, which significantly reduced the hydrogenation activity of benzene. However, Ni/NA-MOF-450 catalyst reduced at 450 ℃ can effectively resist the metal Ni agglomeration caused by the collapse of MOFs structure at high temperature, and has better hydrogenation activity of benzene. [ABSTRACT FROM AUTHOR]

• The physical characterization and antifungal activities of Cu and Cu 2 O nanoparticles are studied. • Cu and Cu 2 O nanoparticles exhibited very good results in inhibiting different Colletotrichum spp. • C. asianum treated with 0.50 mg/mL of Cu 2 O nanoparticles showed a morphological alteration. In this work, the physical characterization and antifungal activities of Cu and Cu 2 O nanoparticles were investigated. The X-ray diffraction results confirmed that Cu and Cu 2 O nanoparticles were obtained with a crystalline nature. According to transmission electron microscope results, Cu nanoparticles were found to be quasi-rounded with a size of ∼ 0.25 μm, whereas Cu 2 O nanoparticles were quasi-faceted with a size of ∼ 0.15 μm. Furthermore, Cu and Cu 2 O nanoparticles exhibited very good results for inhibiting different Colletotrichum spp. at concentrations of 1 mg/mL under in vitro conditions. Based on scanning electron microscopy results, C. asianum treated with 0.50 mg/mL of Cu 2 O nanoparticles showed a morphological alteration. [ABSTRACT FROM AUTHOR]

• In-situ metal nanoparticle formation using electron beam in polymer complex. • Easy synthesis of integrated metal nanoparticle with ceramic substrate. • Fabrication of nano-wire and nano-particles. Polydopamine (PDA) is a biopolymer inspired by the mussel chemistry. Due to its capability to bind various metal-ions, PDA has been explored in several potential applications including absorbents for heavy metal contaminants and templates for nanoparticle growth. In this study, metal-ion-containing PDA was prepared by introducing Cu, Ni, and Co cations during synthesis. We discovered that nanoparticles (NPs) formed under intense electron beam irradiation. For Cu-containing PDA, both equiaxed NPs and rod-like nanocrystals were observed. In contrast, Ni and Co NPs were mainly equiaxed with smaller diameters. The formation of metal NPs is likely a result of electron beam induced reduction. We also demonstrated that electron beam could induce growth of Cu NPs on the surface of PDA-coated SiO 2 particles. This result suggested that PDA coating could be used as a platform to grow metal NPs on ceramics and potentially other substrates. [ABSTRACT FROM AUTHOR]

• Graphene and silver nanoparticles (AgNPs@GO) composite is prepared as lithium anode. • The AgNPs@GO structure offers the Ag active sites to induce the lithium deposition. • The hollow and multi-layer AgNPs@GO exhibits space-confined feature of Li storage. • AgNPs@GO reveals low nucleation overpotential and stabilized Li storage performance. A flower-like oxidized graphene and metal silver nanoparticles composite (AgNPs@GO) was prepared by a spray-drying and annealing process. The AgNPs@GO exhibits three-dimensional (3D) multi-layer heterojunction structure and high surface area, which can reduce the overpotential of lithium deposition, decrease lithium dendrites, and stabilize lithium storage. Especially, an excellent electrochemical performance is obtained due to the space-confined feature of AgNPs@GO structure. At 0.25 mA cm−2 for 0.5 mAh cm−2, the AgNPs@GO-300 reveals a hysteresis voltage of only 32.3 mV at the 10th cycle and a stable coulombic efficiency of 97.1% after nearly 1000 h cycles, indicating promising prospects as lithium metal anode. [ABSTRACT FROM AUTHOR]

• Unexpected free radical scavenging properties of the material. • Material insoluble in most solvents to be a recyclable heterogeneous free radical scavenger. • Easily prepared material free of additional oxidant. • Stable material stored under normal conditions. Reaction of aniline with KMnO 4 could produce polyaniline-supported Mn nanocomposites (Mn@PANI). In comparison with conventional method for the synthesis of PANI-supported metal nanoparticles, this reaction did not require additional oxidant. As a Mn-containing material, Mn@PANI was initially expected to be a good catalyst for oxidation reaction and its catalytic activity was tested by using the oxidative deoximation reaction. Surprisingly, instead of the expected catalytic activity, the material restrained the reaction on the contrary. It was found to be an easily removable heterogeneous free radical scavenger that could inhibit the unwanted decomposition reactions caused by free radicals so that the lifetime of the chemical products could be extended. [ABSTRACT FROM AUTHOR]

• Ag/NC was in situ synthesized by solution plasma process. • The ORR activity of Ag/NC proceeded via the coexistence of two and four-electron pathways. • Enhanced ORR activity of Ag/NC was attributed to the synergistic effects of Ag and NC. • Solution plasma process shows the promising way to in situ synthesize metal nanoparticles supported on carbon materials. Silver nanoparticles supported on nitrogen-doped carbons (Ag/NC) were in situ synthesized by a solution plasma process. In the solution plasma, Ag nanoparticles were produced via the sputtering of Ag electrode, while the NC supports were simultaneously synthesized from 2-cyanopyridine (C 6 H 4 N 2). The results of the characterization show that Ag nanoparticles had good crystallinity and the NC supports possessed an amorphous structure. The oxygen reduction reaction (ORR) catalyzed on Ag/NC proceeded via the co-existence of two and four-electron pathways in alkaline solution, with the four-electron pathway being found to be more dominant. An enhanced ORR activity of Ag/NC was attributed to the synergistic effect of Ag nanoparticles and NC supports. Moreover, Ag/NC exhibited long-term durability and high resistance to methanol oxidation in comparison with the commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Synergistic interaction of metal oxide nanoparticles and carbon based structures. • Carbon nanotubes decorated with hafnium dioxide nanoparticles. • Hybrid nanocomposite for solar energy harvesting. • Photocurrent generation under visible light photoexcitation. • 200 nA of photocurrent for 1 mg of the nanocomposite. Abstract We report on the photocurrent generation in HfO 2 -carbon nanotube (CNT) nanocomposites under Ultra-Violet (UV) and visible excitations at zero bias. Cubic phase HfO 2 nanoparticles have been combined with multi-walled carbon nanotubes in this work. The cubic phase of HfO 2 has been stabilized by oxygen vacancies which act as luminescent band gap states. In a broad UV–visible range of below band gap photoexcitation, a photocurrent is generated which was found to be most efficient under UV illumination. We discuss the possible mechanism in terms of a CNT assisted charge transfer involving optically active surface states of the HfO 2 nanoparticles. The abrupt generation and relaxation responses of the photocurrent on/off cycles along with a constant steady state current as high as 200 nA for 1 mg of the nanocomposite, has potential in energy harvesting and other applications requiring stable charge retention. [ABSTRACT FROM AUTHOR]

Graphical abstract Fabrication of anodic aluminum oxide template with two step anodization and its decoration with BFO and LBFO nanoparticles. Highlights • Fabrication of uniform nano-porous AAO template using two step anodization. • Synthesis and decoration of AAO templates with BFO and LBFO nanoparticles. • Pore size decreases with decoration of nanoparticles. • A significant increase in absorption was recorded. • Band gap was found to decrease in decorated templates. Abstract Anodic aluminum oxide templates with pore size 70 nm were fabricated using two step anodization processes. BiFeO 3 and La doped BiFeO 3 nano-particles were synthesized and decorated on anodic aluminum oxide templates to explore its various physical properties. Crystallographic studies reveals the formation of rhombohedral geometry with 166-R-3m space group. Pore size, morphology and elemental compositions of host and decorated templates were analyzed with field emission scanning electron microscopy and energy dispersive X-ray spectroscopy. Optical studies demonstrate enhanced absorption and significant decrease in band gap of host template with decoration of nanoparticles. [ABSTRACT FROM AUTHOR]

Highlights • Carbon supported MgO coated PtSn particles were synthesized by a polyol method. • PtSn particles growth upon annealing was reduced by a MgO shell. • The structural stability of PtSnMg/C was higher than that of PtSn/C. • The electrochemical stability of PtSnMg/C was higher than that of PtSn/C. Abstract To prevent sintering of carbon supported metal nanoparticles during high temperature annealing in reductive conditions, Pt-Sn nanoparticles were coated with MgO. The agglomeration of Pt-Sn particles upon thermal annealing was significantly inhibited with a MgO shell. The presence of the oxide shell gave rise to a more homogeneous microstructure and a better electrochemical stability. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • First report on the synthesis of cheap metal nanoparticles on PANI via an environment-friendly method. • Low cost of the materials fabrication. • Green procedures free of the generation of solid waste. • Highly dispersed copper nanoparticles on PANI support. • Overwhelmingly better catalytic activities in C N coupling reactions than the materials prepared via conventional method. Abstract Cheap metals, such as Cu, can not catalyze aerobic oxidative polymerization of anilines because of insufficient electric potential differences between their high and low valent ions. Therefore, conventionally, preparation of cheap metal nanoparticles supported on polyanilines (nano M@PANIs) inevitablly requires chemical oxidants such as (NH 4) 2 S 2 O 8 that generate solid wastes. In this work, we found that, by using H 2 O 2 as the green oxidant, nano Cu@PANI could be easily prepared without solid waste generation. In the material, copper nanoparticles highly dispersed on the waxberry-like nano PANI support and possessed overwhelmingly better catalytic activities in C-N coupling reactions than Cu@PANIs prepared via (NH 4) 2 S 2 O 8 oxidation method. This should be the first example for the synthesis of cheap metal nanoparticles on PANI via an environment-friendly method and might be a breakthrough in the field of nano M@PANIs investigation to expand the application scopes of these materials for low cost and green features. [ABSTRACT FROM AUTHOR]

Highlights • SnO 2 (TiO 2) spherical particles film was grown directly on FTO by TiCl 4 treated. • SnO 2 (TiO 2) spherical structures are composed of 1D single crystal nanorods. • SnO 2 (TiO 2)/CdS(5)/CdSe(4) photoelectrode showed preferably PEC properties. Abstract Herein, SnO 2 spherical structure was directly deposited on FTO substrate by hydrothermal synthesis. As light absorber, CdS and CdSe nanoparticles were assembled onto the TiCl 4 -treated SnO 2 spherical particles (SnO 2 (TiO 2)) films by using SILAR method. The number of CdS and CdSe deposition cycles that influence the optical and photoelectrochemical performance of the photoelectrodes are evaluated. The best-performed sample is the co-deposition of 5 cycles of CdS and 4 cycles of CdSe on SnO 2 (TiO 2) photoelectrode, and its photocurrent density is about 2.61 mA cm−2 versus Ag/AgCl at 0 V. The significant photoelectrochemical performance is due to a synergistic contribution from the enhanced light absorption range of the hybrid nanocomposite and the formation of type-II heterostructure, which plays important role in the effective charge separation process. Our results show that CdS/CdSe co-deposition SnO 2 (TiO 2) photoelectrode may have great potential application in photovoltaic field. [ABSTRACT FROM AUTHOR]

Highlights • Green synthesis of CeO 2 nanoparticles was demonstrated using Jatropha curcas plant extract. • Four-fold particle size of CeO 2 reduced by Jatropha curcas than chemical stabilizer. • Bandgap energy of green synthesized CeO 2 showed strong blue shift compared to bulk material. • Photocatalytic acetaldehyde degradation was demonstrated at different CeO 2 nanoparticles. Abstract In this report, we demonstrate the advantage of Jatropha curcas plant extract as particle reducing agent in stabilizing cerium oxide (CeO 2) nanoparticles. The toxic-free, green Jatropha curcas extract mediated CeO 2 nanoparticles has tested in photocatalytic degradation of indoor gaseous pollutant acetaldehyde and compared with conventional chemically synthesized CeO 2 nanoparticles (NH 3 and NaOH). The results showed green synthesized CeO 2 nanoparticles are effectively reducing the particle size 3–5 nm and homogenous particle distribution compared to chemically synthesized CeO 2 (18–25 nm). As a result, it exhibits effective photocatalysis performance in acetaldehyde degradation. [ABSTRACT FROM AUTHOR]

Highlights • Monodisperse colloidal Cu 2-x S nanoplates were synthesized by a wet chemical method. • The reaction is thermodynamic driven. • Large Cu 2-x S nanoplates growth at the expense of smaller ones. • Ostwald ripening produces large lateral sized two-dimensional Cu 2-x S nanoplates. Abstract Large lateral sized two-dimensional (2-D) colloidal nanocrystals with a uniform thickness are highly desired but difficult to prepare. Herein we demonstrated that colloidal copper (I) sulfide (Cu 1.75 S) nanoplates with an large lateral dimension, i.e. 200 nm to 1 μm, can be successfully produced from small Cu 2-x S nanoplates via an Ostwald ripening process. The availability of the large lateral sized Cu 2-x S nanoplates produced through this approach not only sheds light on the construction of 2-D nanostructures of other systems but also provides a platform for the cation exchange reaction to generate a variety of 2-D nanoplates with large lateral dimensions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A Pd/C catalyst involving sequential ligand exchange of an anionic Pd precursor was developed. • The sequential ligand exchange method enabled the formation of extremely small and monodisperse Pd nanoparticles. • The resulting Pd/C catalyst showed excellent activity for the direct synthesis of H 2 O 2. • The catalytic activity was significantly affected by the particle size and electronic nature of Pd. Abstract A new catalyst preparation method involving the sequential ligand exchange of anionic palladium complexes to cationic complexes via the formation of palladium hydroxide intermediates is proposed. The novel method enables the electrostatic adsorption of an anionic palladium complex on the negatively charged carbon surface, and therefore makes it possible to obtain small and highly dispersed Pd nanoparticles. The H 2 O 2 productivity and H 2 selectivity of the ligand-exchanged catalyst were 16 and 3.6 times higher than those of the Pd/C catalyst prepared by using the same anionic palladium precursor. The strikingly different activities mainly attributed to the difference in the nanoparticle size and the oxidation state of Pd, which clearly indicates that the activity of Pd/C catalyst for the direct synthesis of H 2 O 2 can be greatly improved by the sequential ligand exchange method. [ABSTRACT FROM AUTHOR]

Highlights • Nano-Bi particles were synthesized at CNT matrix as fluoride ion electrochemical material. • The Bi-NMO battery shows a capacity of 109.5 mAh/g for 80 cycles with 100 mA/g. • The fluoride ion diffusion efficiency was obtained using various scan rate of CV test. • The aqueous dual ion battery can be easily assembled in open air environment. Abstract The NaF dual-ion battery was demonstrated as potential battery where fluoride and sodium ions were extracted from NaF electrolyte respectively during discharging; while the charging process causes the release of ions to the electrolyte. However, previous studies reveal that electrode configuration with large-sized particles will significantly reduce the energy density and stability. Herein, we proposed a novel hybrid electrode assembly of bismuth nanoparticles/carbon nanotubes (nano-Bi@CNTs), which could achieve the excellent electrochemical stability. The new NaF dual-ion battery, consisting of nano-Bi@CNTs-Na 0.44 MnO 2 (NMO), demonstrates a high specific capacity of 109.5 mAh/g after 80 cycles with 100 mA/g current density. Moreover, the electrochemical mechanism of fluoride ion in this system was comprehensively investigated. The current research is significant for the novel anion energy storage system. [ABSTRACT FROM AUTHOR]

Photocatalytic activity of low band gap hydrogenated HfO 2 doped TiO 2 (H-HfO 2 /TiO 2 ), HfO 2 doped TiO 2 (HfO 2 /TiO 2 ) and TiO 2 (pristine) were investigated by photocatalytic degradation of five different industrial dyes. The current study envisages the effect of doping hydrogen and HfO 2 up on TiO 2 for photocatalytic degradation of different chemically structured dyes. Methylene Blue attains fast degradation efficiency of 90%, within 10 min of the reaction due to high photocatalytic adsorption and degradation over the rough TiO 2 surface. Effect of pH on dye degradation is observed, leading to disintegration and mineralization. [ABSTRACT FROM AUTHOR]

L1 0 -Mn 55 Ga 45 was synthesized by arc melting, followed by posted annealing. FeCo nanoparticles were synthesized by a wet chemistry process. L1 0 -Mn 55 Ga 45 /FeCo composites were synthesized by cryogenic ball milling. In three different bathes, the FeCo mass percentage was controlled as 5%, 10% and 15%, respectively. The magnetic exchange coupling between FeCo and L1 0 -Mn 55 Ga 45 was investigated by VSM. The results showed that when FeCo was 5% and 10%, effective exchange coupling and increased maximum energy product were observed in the composites. However, when the FeCo mass percentage was increased to 15%, both magnetic exchange coupling and maximum energy products were reduced in the composite. [ABSTRACT FROM AUTHOR]

A novel room temperature (RT, 25 °C) NO 2 gas sensor by utilizing porous silicon (PSi)/V 2 O 5 nanopillars (VONPs) decorated with Pd nanoparticles as sensitive materials was successfully synthesized via a facile methods that reduction of a Pd solution followed by thermal annealing of V film on PSi substrate. The NO 2 -sensing analysis revealed that the PSi/VONPs-Pd showed obviously enhanced response and selectivity towards NO 2 , as compared to PSi/VONPs and Si/VONPs. The maximum response of PSi/VONPs-Pd sensor was performed at RT, therefore it has great potential to be used as a RT NO 2 gas sensor in practical. The mechanism of gas sensing and enhanced gas response of PSi/VONPs-Pd was discussed. [ABSTRACT FROM AUTHOR]

High strength and transparent nanocomposite hydrogels (AD gels) were prepared by photo-initiated free radical copolymerization of acrylic acid (AA) and N, N-dimethylacrylamide (DMAA) in the colloidal solutions of alumina nanoparticles (Al 2 O 3 NPs). The obtained hydrogels displayed well-defined porous structures and outstanding mechanical properties with tensile and compressive strength up to 1.88 MPa and 28 MPa, respectively. The FT-IR spectra indicate that there exist strong chelation reactions between Al 2 O 3 NPs and polymer matrix, which are responsible for the formation of AD gels and their excellent mechanical performance. Moreover, AD gels with low swelling ratios could be prepared by choosing appropriate monomer ratios, endowing the hydrogels with considerable mechanical strength even at swollen state. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flow of the melt during the SLM process is simulated by finite element method. • Flow velocity of melt is mainly related to the scanning speed rather than laser power. • Nano-W composite high Nb-TiAl alloys were successfully fabricated via SLM. • Elemental nano-W can be detected regardless of any scanning speeds. • Nano-W particles not only play the role of heterogeneous nucleation, but block columnar grains grow. The microstructure instability of high Nb-TiAl alloy at high temperature for a long time severely limits the use of TiAl alloys in more complex environments. Refractory metal W nanoparticles can effectively stable microstructure as an additional second phase due to its high melting point. Meanwhile, the microstructure can be further refined by combining additive manufacturing technology. In this work, the flow of melt during the selective laser melting (SLM) process is simulated by finite element method, and the melt flow behavior is mainly affected by the scanning speed. Preparation of nano-W composite TiAl alloys by SLM, and the higher scanning speed, the nano-W particles tend to more uniform dispersion. Nano-W particles not only plays the role of heterogeneous nucleation, but block columnar grains growth, and finally forming the randomly oriented equiaxed grains microstructure. [ABSTRACT FROM AUTHOR]

Fullerene-like hydrogenated carbon films deposited by plasma enhanced chemical vapor deposition (PECVD) as compared with other methods can attain super-low friction and wear. But they often have bad adhesion to steel substrate and their structures are tailored by non-metal elements as F, N etc. In this work, we have prepared the films on steel balls by the combination of PECVD and plasma nitriding, among which iron nitride particles are sputtered and introduced in the films. The films have longer wear life and better adhesion to the steel substrate due to the N diffusion from iron nitride particles to the atom matrix of the ball. [ABSTRACT FROM AUTHOR]

This paper reports a facile two-step hydrothermal method for the fabrication of f-ZnO@Fe 2 O 3 nanostructures. Various characterization results show that the hierarchical nanocomposites are formed by the loading of well-crystallized α-Fe 2 O 3 nanoparticles onto the flower-like ZnO. The nanostructures exhibit large specific surface area and narrow mesoporous size distribution. Morphological measurements indicate that Fe 2 O 3 nanoparticles are densely and uniformly attached onto the entire surface of the f-ZnO. The catalytic performance of the f-ZnO@Fe 2 O 3 on the thermal decomposition of AP is measured by TG and DTA methods. The results demonstrate that the f-ZnO@Fe 2 O 3 nanostructures can lower the decomposition temperature and accelerate the decomposition process of ammonium perchlorate, which may be presumably ascribed to the synergistic effect between f-ZnO and α-Fe 2 O 3 nanoparticles. [ABSTRACT FROM AUTHOR]

In this work, nanoparticles assembled SnO 2 nanosheet structures are synthesized through a facile hydrothermal route. The as-synthesized SnO 2 products are characterized through X-ray diffraction spectroscopy (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and specific surface area analyzer. Simultaneously, the as-synthesized products are studied for degradation of several organic dyes and removal of heavy metal ions (Fe 3+ and Ni 2+ ). The results show the as-synthesized SnO 2 products possess excellent photocatalytic activities and good removal abilities to Fe 3+ and Ni 2+ , which could be attributed to large specific surface area and unique structure of the as-synthesized SnO 2 products. It demonstrates that the as-synthesized SnO 2 nanosheets possess potential applications in wastewater purification. [ABSTRACT FROM AUTHOR]

An advanced architecture design of Bi 2 WO 6 nanoparticles anchored on 3D graphene framework composites as anode material for Li-ion batteries was synthesized by hydrothermal method and sintering. The structure and morphology of the products were characterized by XRD, SEM and TEM. The electrochemical performances of the prepared composites were investigated by galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. Results showed that the first capacity of Bi 2 WO 6 /graphene was 715.2 mAh g −1 at 50 mA g −1 , and it remains as high as 510.1 mAh g −1 after 50 cycles. Moreover, the Bi 2 WO 6 /graphene composites displayed superior rate capability. All tests proved that the Bi 2 WO 6 /graphene oxide composites showed excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

A flexible and highly sensitive Surface-Enhanced Raman Scattering (SERS) film with PMMA/Ag/graphene/Ag/graphene hybrid structure was designed and prepared, which showed about a 2-fold enhancement in Raman signals of R6G molecules, compared with PMMA/Ag nanoparticles/graphene substrate. The SERS substrate provides very high sensitivity to R6G molecules reaching a detection limit of 1 × 10 −8 M. The substrate can be attached directly on the tested sample owing to its excellent flexibility. In the SERS test on the malachite green (MG) soaked fish samples, the use of such substrate makes the in-situ detection being accomplished within 5 min under sensitivity of 10 −7 M, which shows very high practical utility. [ABSTRACT FROM AUTHOR]

In this study, we developed a facile synthetic method for the preparation of nanostructured sodium cobalt fluoride (NaCoF 3 ). Uniform NaCoF 3 nanoparticles with small-crystallite size were synthesized through a simple solvothermal process using relatively inexpensive precursors. The NaCoF 3 particles obtained were composed of small nanoparticles (∼20 nm) assembled to form large nanoparticle clusters (NPCs, ∼200 nm). This unique nanostructure provided a large surface area (>40 m 2 g −1 ) of NaCoF 3 . Furthermore, the effects of reaction conditions and an essential additive (trisodium citrate) were also investigated using analytical techniques, and the importance of the optimal conditions to obtain uniform NaCoF 3 NPCs without impurities was demonstrated. We expect that this synthetic method will initiate further research into the development of various nanostructured sodium metal fluorides and their applications. [ABSTRACT FROM AUTHOR]

Here, we report the effects of zinc alloying in iron pyrite (FeS 2 ) nanoparticles (NPs). The NPs were synthesized by a hot-injection method using oleylamine (OAm) only, with no other ligand. The band-gap and morphology were found to be strongly dependent on the relative amount of zinc incorporated in the nanoparticles. A blue shift was observed in Raman active modes for FeS 2 upon Zn incorporation which has been ascribed to the change in the bond length of (S 2 ) 2− dumbbells in the pyrite structure. According to the optical absorption measurements the band-gap (E g ) of NPs increased linearly with the mole fraction of Zn in the precursor solution (Zn i ) for the NP synthesis, and an enhancement of ∼0.08 eV was achieved for Zn i = 40%. Also, the shape of NPs varied from cubic to quasi-cubic with the increase in the mole fraction of Zn in the precursor. [ABSTRACT FROM AUTHOR]

• A carbon-coated liquid metal nanoparticles anode is successfully prepared. • The excellent morphology and electrochemical performance of carbon-coated liquid metal nanoparticles are reported. • The carbon layer can alleviate the volume effect and inhibit the mutual fusion. Ga-based liquid metal has been reported as a self-healing anode for lithium-ion batteries due to their good fluidity and surface tension. However, the materials still face the challenge of poor long-term stability due to mutual fusion and volume expansion. In this work, the pristine liquid metal nanoparticles (LMNPs) are prepared by the ultrasonic stirring method. And then polydopamine-coated LMNPs (LMNPs@PDA) is obtained by the polymerization of dopamine. Finally, the carbon-coated LMNPs (LMNPs@C) are obtained by annealing under an Ar atmosphere. The carbon layer can efficiently alleviate the volume effect and prevent the mutual fusion of LMNPs@C maintaining its high specific surface area and capacity. The LMNPs@C anode achieves the initial capacity of 959.9 mAh g−1 and a discharge capacity of 452.1 mAh g−1 at 0.2 A g−1 after 100 cycles. Besides, under the current density of 5 A g−1, the LMNPs@C anode still maintains the discharge capacity of 185 mAh g−1. Moreover, the LMNPs@C anode maintains a low R ct and a high lithium-ion diffusion coefficient due to the carbon layer equipping good conductivity. [ABSTRACT FROM AUTHOR]

Ti microfibers with a diameter of 20 μm were used as a three dimensional conductive back contact for a tungsten oxide (WO 3 ) photoelectrode. We coated the microfibers with WO 3 nanoparticles by a solution-based dip coating step and heat treatment at 650 °C. A high loading of WO 3 nanoparticles was achieved over a large surface area of the porous microfibers through the use of a high viscosity solution for the dip coating. The prepared WO 3 -coated Ti microfibers exhibited enhanced photoelectrochemical properties. Visible light response was improved in the conductive Ti microfibers owing to increased absorption of visible light and efficient extraction of photoexcited electrons at the large interface. [ABSTRACT FROM AUTHOR]

In order to enhance the bonding strength of joints by using Cu nanoparticles paste at a relative low bonding temperature and a suitable pressure, a novel mixed Cu nanoparticles of 20 nm and 100 nm (in diameter) paste for Cu-Cu joints was investigated in this study based on the density increment of packing two different sizes of spheres. The optimized mass ratio of 20–100 nm nanoparticles for maximum sintering density was proposed (9/1) by simulation and experiments. The bonding strength of joints over 15 MPa was achieved even at a lower bonding temperature of 250 °C and pressure of 4 MPa. [ABSTRACT FROM AUTHOR]

We developed a one-pot preparation method of Pd nanoparticles (NPs) supported on graphene (Pd/G) by using Pd electrode plasma treatment of aqueous KCl solution containing graphene. It was found that Pd NPs were formed from the Pd electrodes during the plasma treatment and they were supported on graphene. The number of Pd NPs on graphene increased with increasing plasma treatment time, but the size of the Pd NPs was almost the same among different plasma treatment time. From the results of FT-IR and Raman spectra of the products, the formation of C O and defect on graphene were confirmed. The prepared Pd/G showed a superior catalytic activity for the hydrogenation of nitrobenzene to aniline to Pd NPs on α-Al 2 O 3 , which was prepared by the same plasma method in the presence α -Al 2 O 3 instead of graphene. [ABSTRACT FROM AUTHOR]

In this study, a pulse-mode electrochemical deposition technique was employed to deposit dense and homogeneous Ni nanoparticles on the three-dimensional graphene network (3DGN) as the catalysts for growing the vertical aligned one-dimensional carbon nanofibers (CNFs) to fabricate the full-carbon hybrid nanoarchitecture of CNFs/3DGN for the supercapacitors. When tested as electrode for a supercapacitor, the CNFs/3DGN hybrid nanoarchitecture demonstrated to possess a large surface area and showed an excellent specific capacitance of 59.28 F g −1 at a current density of 0.17 mA cm −2 , also displayed good cycle stability with capacitance retention of 93.9% after 10,000 cycles in 6 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

We report a new approach for the fabricating of Au-Ag alloy nanoparticles confined in Al 2 O 3 matrix using pulsed laser deposition method. High resolution transmission electron microscopy and X-ray photoelectron spectroscopy analysis clearly reveal that Au-Ag alloy with the concentration of Au/Ag ratio of about 1:1 are fabricated in the insulating Al 2 O 3 layer. Interestingly, the Au-Ag alloy nanoparticles show a distinct PL band. The findings provide a physical insight and offer useful methodology to synthesize metallic alloy nanoparticles for potential application in photonic devices. [ABSTRACT FROM AUTHOR]

Highly crystalline mesoporous γ-MnS nanospheres were prepared through a facile one-step hydrothermal method. The obtained γ-MnS nanospheres were around 1 µm in diameter and assembled from nanoparticles. The mesoporous γ-MnS nanospheres were investigated as anode materials for lithium ion batteries with excellent cycling stability and reversible capacity. In detail, at a current density of 200 mA g −1 , the discharge capacity of mesoporous γ-MnS nanospheres remained at 350 mAh g −1 after 300 cycles. [ABSTRACT FROM AUTHOR]

We proposed a facile method to prepare ZnO@g-C 3 N 4 core/shell type photocatalyst via a two-step calcination. Thin layer of g-C 3 N 4 was homogeneously coated on ZnO nanoparticles with well-defined interface, which reduces the charge transfer resistance and results in distinct PL quenching. Therefore, the as-prepared ZnO@g-C 3 N 4 demonstrates significant photocatalytic improvement under visible-light irradiation than ZnO (~35 times) and g-C 3 N 4 (~5 times) due to the effective charge separation and suppressed carrier recombination. Moreover the ZnO@g-C 3 N 4 photocatalyst shows high stability which retains ~90% of its initial activity after 5-cycle reuse. [ABSTRACT FROM AUTHOR]

Porous NiO architecture has been successfully prepared by calcining a novel Ni-MOF in air. As revealed by XRD, SEM and TEM, the obtained NiO architecture is assembled from two-dimensional nanosheets, which primarily consist of uniform nanoparticles and large quantities of pores between nanoparticles. Electrochemical data present that the NiO architecture possesses a reversible specific capacitance of 324 F g −1 after 1000 cycles at 1 A g −1 , and nearly 46% capacity retention when the current density increases from 1 to 40 A g −1 , suggesting its promising application in supercapacitors. [ABSTRACT FROM AUTHOR]

Synthesis conditions have important impacts on the properties of ultrafine nanoparticles; understanding the interdependences of such properties on specific synthetic parameters can lead to controlled and optimized products. Here we discuss the effect of coprecipitation conditions during the synthesis of ultrafine yttria stabilized zirconia (YSZ) nanoparticles and gadolinium doped YSZ. We focused on the effect of ammonia concentration as precipitating agent. Although based on the nucleation theory one expects smaller particle sizes for higher concentrations of NH 4 OH, the usage of 1 M or 5 M of NH 4 OH lead to similar grain sizes (<6 nm). However, the more concentrated condition led to highly agglomerated powders. This was attributed to an increase in the ionic force in the precipitating environment that caused particle coagulation. The resultant powders thus showed significantly different densification behaviors during sintering using spark plasma sintering, with the agglomerated powders achieving lower relative densities. [ABSTRACT FROM AUTHOR]

Hollow NiCo 2 O 4 nanoparticle/graphene composite was firstly fabricated by a template-free method via a hydrothermal route combined with a two-step annealing treatment in N 2 and air atmosphere, respectively. The structure and morphology of the composite were studied by XRD, XPS, FE-SEM and TEM. As a supercapacitor electrode material, the hollow NiCo 2 O 4 nanoparticle/graphene composite showed high specific capacitance (1238 F g −1 at 1 A g −1 ) and excellent cycle stability. The excellent electrochemical performance may be ascribed to the synergistic effect between the conductive graphene and the hollow structure of NiCo 2 O 4 nanoparticle. This work showed that the hollow NiCo 2 O 4 nanoparticle/graphene composite should be a promising electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

This paper reports the structural as well as the magnetic properties of ZnS:Eu 3+ (0, 1, 2, 3, and 4 at%) nanoparticles prepared by a hydrothermal method. The compositional, structural and magnetic properties of ZnS:Eu 3+ nanoparticles were investigated by energy dispersive X-ray spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry (VSM) measurements. XRD studies confirmed that all the samples had a cubic structure with good crystallinity. TEM showed that the particles were polycrystalline with a mean size of 5–8 nm. XPS revealed the oxidation state of the Eu in the ZnS lattice to be +3. All the Eu 3+ -doped ZnS nanoparticles exhibited room temperature ferromagnetic behavior as a function of doping concentration. The observed RTFM may be interpreted by the contribution of the magnetic moments from the unpaired 4 f electrons of Eu 3+ in the ZnS:Eu 3+ nanoparticles. The interesting magnetic properties of ZnS:Eu 3+ nanoparticles may be further explored for new generation spintronic devices. [ABSTRACT FROM AUTHOR]

Li 4 Ti 5 O 12 hollow microspheres assembled by nanoparticles are successfully prepared via a process employing hydrothermal method and subsquent calcination. The washing times, which can significantly influence the adsorbed amount of Li + in the intermediate products, play an important role in the composition of the final hollow microspheres. The obtained hollow microspheres present a very stable reversible capacity of 173 mAh g −1 at 1 C. Furthermore, the Li 4 Ti 5 O 12 hollow microspheres could remain relatively high reversible capacities even at higher charge/discharge rates. The reversible capacities of approximately 168.3, 163.0, 156.6 and 152.4 mAh g −1 are obtained after 10 cycles at 2 C, 5 C, 10 C and 15 C, respectively. [ABSTRACT FROM AUTHOR]

A promising electrode material barium manganate (BaMnO 3 ) for electrochemical supercapacitor was prepared by solution combusted manganese tartrate complex process. Several analytical tools such as X-ray diffractometry, FT-IR spectroscopy, diffuse reflectance spectra, TG/DTA, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been used to characterize the BaMnO 3 nanomaterial. Electrochemical properties of the synthesized composites were elucidated by cyclic voltammetry and galvanostatic charge–discharge measurements. This material showed excellent cycling capability, even at the high current and excellent capacity retention with the best combination of coulombic efficiency of 93.9% and specific capacitance of 141.6 F g −1 after 500 cycles. These results clearly indicate the high rate discharge performances of BaMnO 3 and it can be recognized as high-performance electrode material. [ABSTRACT FROM AUTHOR]

Abstract In recent years, the production of biodiesel has rapidly increased due to its benefits and to resolve the problem findings present in environmental pollution. In, this study barium salts doped with cerium oxide are used as a heterogeneous catalyst for the production of biodiesel from Cordiamyxa oil. The synthesized BaMoO 4 -Ce 2 O 3 nanocatalyst has characterized by XRD (X-ray powder diffraction) and SEM (Scanning Electron Microscope) analysis. Methanol to a molar ratio of oil from 12:1 to 16:1 has studied and got the optimized results. An optimum yield of 87.50 wt% of methyl esters collected from Cordiamyxa bio-oil with optimized limits of 0.5 wt% of catalyst BaMoO 4 -Ce 2 O 3 at 65 °C. The purpose of the current study investigates the analysis of biodiesel and their blends with diesel oil in four-stroke internal combustion engine (ICE) applications like unburned hydrocarbons, sulfates, particulate matter, polycyclic aromatic hydrocarbon, carbon monoxide, and nitrate aromatic hydrocarbons. Cordiamyxa methyl ester blend (Biodiesel-B20) with BaMoO 4 -Ce 2 O 3 nanoparticles shows a better engine performance and emission reduced compared to fossil fuels like decrease hydrocarbon particulate matters. [ABSTRACT FROM AUTHOR]

Highlights • ZnFe 2 O 4 NPs were synthesized using cost effective sol-gel auto-combustion method. • The structure and morphology of ZnFe 2 O 4 NPs were studied using XRD and SEM. • Anti-candida and anti adhesion activity of ZnFe 2 O 4 NPs was studied. • ZnFe 2 O 4 NPs were found potential candidate in Anti-candida and anti adhesion application. Abstract Present work is intended to study the anti-candida and anti-adhesion efficiencies of zinc ferrite nanoparticles (ZnFe 2 O 4 NPs), obtained by using a simple, cost-effective sol-gel auto-combustion method. Results of this study suggest that the ZnFe 2 O 4 NPs hold the potential for anti-candida activity, also capable to restrict the 99% cell adhesion and can be a promising nanomaterial against Candida albicans. [ABSTRACT FROM AUTHOR]

Flower-like CuO/ZnO hierarchical structures were prepared via a flexible two-step synthesis method, in which nanorods-assembled flower-like ZnO microstructures with the diameter about 430–1680 nm and the length about 3.6–8.8 μm were prepared in advance through a chemical solution method, and then a frost-like layer of CuO nanoparticles (NPs) decorated on the surface of ZnO nanorods (NRs) via an ionic-layer adsorption and reaction method. Compared with pure ZnO NRs, the flower-like CuO-decorated ZnO NRs show an obvious improvement in gas sensing performance. The gas sensing mechanism of the CuO-decorated ZnO NRs was discussed in relation to the catalytic effect of CuO and the introduction of the p-n junction between CuO and ZnO. [ABSTRACT FROM AUTHOR]

Iron nanoparticles were observed on the surface of commercial purity aluminum alloys after thermomechanical treatment using a hot rolling tribo-simulator with a roll surface roughness (R a ) of 0.01 µm. These nanoparticles were spherical in shape and possessed an amorphous structure. They were observed lying on the oxide layer of the alloy surface and on crack faces. Iron nanoparticles have not been previously reported on aluminum surfaces under this thermomechanical condition. The surface of the hot rolled aluminum alloy was also covered with fractured iron-rich intermetallic particles embedded into the surface and caught within cracks. [ABSTRACT FROM AUTHOR]

Avoiding dew from the exterior of solar panels is of importance since this may reduce the number of photons hitting the surface. The hydrophilic/hydrophobic coating of GaAs surface with nanostructured ZnO was done by the ultrasound assisted method with the addition of templating agents such as polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG), dodecylamine (DDA), or hexatetramethylene tetramine (HMTA). The best hydrophobic properties and contact angle of 141° were obtained when DDA stabilized ZnO layers were coated on the GaAs. The stability to the scotch-tape test and to outdoor exposure for at least 2 weeks was demonstrated. The XRD, SEM and AFM studies revealed the formation of hierarchical structure consisting of ZnO nanoparticles. The water repulsion effect is explained as being due to the high roughness of the pyramidal shaped layer. [ABSTRACT FROM AUTHOR]

In this paper, we report a high-performance MnO 2 /Ni(OH) 2 nanosheets@nickel foam (MnO 2 /Ni(OH) 2 @NF) electrode material prepared by a facile one-step hydrothermal method. In this novel hierarchical design, nickel foam with a sheath of mesoporous Ni(OH) 2 networks is coated with interconnected MnO 2 nanosheets, which produces a highly porous reticular oxide/hydroxide/metal composite structure. The supercapacitor electrode made of the unique construction exhibits exceptional capacitance of 843.0 F g −1 at a charge/discharge current density of 1 A g −1 and superb rate capability (79.1% capacitance retention from 0.1 to 5 A g −1 ). The synergistic effects are employed to study the competitive advantages of MnO 2 /Ni(OH) 2 @NF electrode. Namely, 3D nickel foam serves as highly conductive backbone for deposition of nanostructured MnO 2 /Ni(OH) 2 composite film, which provides the high accessibility of electrolytic ions for shorten diffusion paths. [ABSTRACT FROM AUTHOR]

Free-standing NiO–MgO composite nanosheet catalysts to be used for catalytic oxy-methane reforming (COMR) have been developed by in-situ growing onto the Ni-foam struts under hydrothermal condition followed by calcination treatment. Among them, the NiO–MgO/Ni-foam consisting of 1.0% MgO, 18.7% NiO and nickel-foam-strut balance is the best structured catalyst engineered from nano- to macro-scale, being capable of converting 82.9% CH 4 into syngas at selectivity of 94.7% to H 2 and of 89.9% to CO for a feed of CH 4 /O 2 =2/1 (vol/vol), at 700 °C and a high gas hourly space velocity of 100 L g −1 h −1 . Nevertheless, improvement of their carbon resistance and textural stability is particularly desirable. [ABSTRACT FROM AUTHOR]

Large scale ZnO nanowire arrays were grown directly on zinc foils using the thermal oxidation in air method. The X-ray diffraction and reflectance investigations confirm that the as-grown nanowires properties are typical for ZnO having a hexagonal wurtzite crystalline structure and band-gap values between 3.2 and 3.3 eV. The scanning electron microscopy images prove that the density and the dimensions (diameter and length) of the ZnO nanowires can be tuned by controlling the oxidation temperature. Wettability studies reveal in the case of Zn foils a hydrophilic behavior with high water droplet adhesion which is transformed into a superhydrophobic one with low water droplet adhesion after the foils' surfaces are covered with ZnO nanowires. Obtaining functional surfaces with such interesting wetting properties using a simple, inexpensive and highly reproducible thermal oxidation in air technique is very attractive for anticorrosion coatings and self-cleaning applications. [ABSTRACT FROM AUTHOR]

A novel and facile approach for synthesis of zinc oxide (ZnO) nanoparticles (NPs) employing homogeneous chemical precipitation followed by hydrothermal heating technique is reported. The present method of synthesis of ZnO NPs is very efficient and cost effective. As-synthesized ZnO NPs were characterized by XRD, FT-IR, EDX, TEM, and N 2 adsorption–desorption (BET) studies. The powder XRD pattern furnished evidence for the formation of hexagonal close packing structure of ZnO NPs having average crystallite size 21.93 nm. The shapes of synthesized ZnO NPs are mostly quasi-cylindrical with sizes 20–50 nm. These ZnO NPs were used as catalysts for the degradation of a pharmaceuticals waste, metronidazole under ultrasound irradiation. [ABSTRACT FROM AUTHOR]