Ternary Nanomaterials Research Articles

Glittering ZnO/Ag/MnO Nano Superstructures for Photocatalytic Applications

ZnO/Ag/MnO ternary heterostructure nanomaterials have been synthesized via cost effective green route using zinc nitrate, manganese acetate and silver nitrate as oxidizers and perished curd as a fuel. The obtained ZnO/Ag/MnO nanomaterials are analyzed using Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), morphological studies by scanning electron microscopy (FESEM), internal structure by transmission electron microscopy (TEM). Both PXRD and FESEM techniques were used to confirm the formation of particles and flakes composition of ZnO/Ag/MnO nanomaterials. Photocatalytic activity of ZnO/Ag/MnO was assessed by varying light source, hydrogen ion concentration, amount of catalyst and amount of dye. The ZnO/Ag/MnO nanoparticles exhibited an enhanced photodegradation of methylene blue dye under visible light.

Graphene encapsulated metallic state Ce2Sn2O7 as a novel anode material for superior lithium-ion batteries and capacitors

We present a strategy to encapsulate bimetallic-based ternary (Ce2Sn2O7) nanomaterials into graphene, which served as an anode material for lithium-ion batteries/capacitors for the first time.

Superior Ethanol Oxidation Electrocatalysis Enabled by Ternary Pd-Rh-Te Nanotubes.

Designing and elaborating cost-efficient Pd-based electrocatalysts for direct ethanol fuel cells is thought to be a significant approach to obliterating the challenge of large-scale practical application of fuel cells. Herein, our group creates a novel class of one-dimensional (1D) PdRhTe nanotubes (NTs) by using H2PdCl4 and RhCl3 as metal precursors and Te nanowires (NWs) as the reductant and sacrificial template. Strikingly, the as-obtained PdRhTe ternary nanomaterials with a unique 1D nanotube structure display a high specific activity of 6.53 mA cm-2 and a mass activity of 2039.2 mA mg-1 for the ethanol oxidation reaction (EOR) in alkaline media, which are 1.25 (1.6) and 1.77 (8.0) times those of PdTe/C and (Pd/C), respectively. More significantly, further electrochemical measurements such as CA and successive CV confirm that the optimized PdRhTe NTs display desirable durability and negligible activity decay. Taking advantage of physicochemical characterizations and electrochemical measurements, we reasonably reveal that the outstanding electrocatalytic performances are derived from the unique geometric structure and synergistic effect. The introduction of Rh facilitates the cleavage of C-C bonds, increasing the self-stability of PdRhTe NTs. In general terms, this work should provide new orientations to synthesize cost-efficient electrocatalysts by a sacrificial template method.

Enhanced visible light photoreduction of aqueous Cr(VI) by Ag/Bi4O7/g-C3N4 nanosheets ternary metal/non-metal Z-scheme heterojunction.

In this paper, we successfully constructed a ternary metal/non-metal nanomaterial which can synergize Z-scheme heterojunction and plasmonic metal/semiconductor for enhancing visible light photoreduction of aqueous Cr(VI). The as-formed ternary metal/non-metal nanomaterial was composed of g-C3N4 nanosheets mutual modified by Ag nanoparticles and Bi4O7. In the ternary nanomaterial, g-C3N4 nanosheets and Bi4O7 fabricated Z-scheme heterojunction, g-C3N4 nanosheets and Ag nanoparticles formed plasmonic metal/semiconductor system, synchronously. The photodeposition experiments were designed to indirect demonstrate the Z-scheme heterojunction via photocatalytic oxidation and reduction deposition reactions, AgNO3 was used as the electron acceptor and Pb(NO3)2 as the electron donor, photocatalytic reduction product and oxidation product were selectively deposited on g-C3N4 nanosheets and Bi4O7, respectively, revealing the Z-scheme heterojunction was definite formed. In addition, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), UV-vis absorption, and Fourier-transform infrared spectroscopy (FTIR) were studied to indicate that the plasmonic metal/semiconductor system was existent in the ternary nanomaterial. The visible light photoreduction of ternary Ag/Bi4O7/g-C3N4 nanosheets was evaluated by photoreducing aqueous Cr(VI). The photoreduction results show that the ternary Ag/Bi4O7/g-C3N4 nanosheets is much higher than the pristine bulk g-C3N4 and g-C3N4 nanosheets.

Architecturally Robust Graphene-Encapsulated MXene Ti2CT x@Polyaniline Composite for High-Performance Pouch-Type Asymmetric Supercapacitor.

A harmonized three-component composite system which preserves the characteristics of individual components is of interest in the field of energy storage. Here, we present a graphene-encapsulated MXene Ti2CT x@polyaniline composite (GMP) material realized in a systematically stable configuration with different ternary nanomaterials for supercapacitor electrodes. Due to the different ζ-potentials in a high-pH solution, chemically converted graphene (negatively charged) is thoroughly unfolded to allow full encapsulation, but the MXene Ti2CT x@polyaniline composite with a low positive ζ-potential is easily attracted toward a counter-charged substance. The obtained GMP electrode exhibits improved cycling stability and better electrochemical performance owing to the use of mechanically robust and chemically inert graphene and the densely intercalated conductive polyaniline between the multilayer MXenes. The GMP electrode has a high gravimetric capacitance of 635 F g-1 (volumetric capacitance of 1143 F cm-3) at a current density of 1 A g-1 with excellent cycling stability of 97.54% after 10 000 cycles. Furthermore, the asymmetric pouch-type supercapacitor assembled using the GMP as a positive electrode and graphene as a negative electrode yields a high energy density of 42.3 Wh kg-1 at a power density of 950 W kg-1 and remarkable cycling stability (94.25% after 10 000 cycles at 10 A g-1).

Microstructure and Chemo-Physical Characterizations of Functional Graphene Oxide-Iron Oxide-Silver Ternary Nanocomposite Synthesized by One-Pot Hydrothermal Method.

In this work, a functional graphene oxide-iron oxide-silver (GO-Fe3O4-Ag) ternary nanocomposite was synthesized by using one-pot hydrothermal treatments of mixture solutions of silver nitrate (AgNO3), ferrous chloride tetrahydrate (FeCl2 4H2O), polyvinylpyrrolidone (PVP), graphene oxide (GO), and ammonium hydroxide solution (NH4OH). The systematic effects of synthesis conditions on the microstructure and formation of binary and ternary composite systems were studied. Importantly, high-crystalline GO-Fe3O4-Ag ternary nanomaterials with average sizes of Fe3O4 particles ~16 nm and of Ag particles ~20 nm were obtained at optimized conditions (125 °C, 2.5 mM of AgNO3 and 5 mL of NH4OH). Magnetic analysis indicated that the saturated magnetization value of Fe3O4-Ag binary composite sample (~73.1 emu/g) was improved as compared with pure Fe3O4 nanoparticles (~60.6 emu/g), while this of GO-Fe3O4-Ag ternary composite sample was about 57.3 emu/g. With exhibited advantages of low-cost, high purity and short synthesis time, the hydrothermal-synthesized GO-Fe3O4-Ag ternary nanocomposite can be a promising candidate for advanced environmental catalyst and biomedical applications.

Carbon-coated single-crystalline LiMn2O4 nanowires synthesized by high-temperature solid-state reaction with high capacity for Li-ion battery

It is a challenge to synthesize highly crystalline nanomorphologies under high-temperature environments. Here, we report that carbon-coated single-crystal LiMn2O4 nanowires were obtained via a high-temperature solid-state method under air environment using carbon-coated MnO2 as the precursor. Without the coated layer of carbon, the obtained LiMn2O4 is bulk. The carbon layer coating on MnO2 acts as a space-limiting layer to maintain the nanowire morphology of the final product of LiMn2O4 during the reaction. Owing to the merits of the highly crystalline, 1D nanowire morphology and the close-coated thin carbon layer, the produced LiMn2O4@C nanowires deliver large capacity and long-term cycling stability. In addition, the space-limiting role of the carbon layer was also found to function for LiMn2O4@C sphere. It is a general strategy to obtain ternary nanomaterials with high crystallinity.

Facile fabrication of polyaniline/multi-walled carbon nanotubes/molybdenum disulfide ternary nanocomposite and its high-performance ammonia-sensing at room temperature

Abstract This paper reports a high-performance room-temperature ammonia gas sensor based on polyaniline/multi-walled carbon nanotubes/molybdenum disulfide (PANI/MWCNTs/MoS2) ternary nanocomposite prepared via in-situ chemical oxidative polymerization method. The component, morphology, crystallinity, and chemical state of PANI/MWCNTs/MoS2 sample was fully inspected by X-ray diffraction (XRD), fourier transform infrared spectrometer (FT-IR), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM), confirming its successful fabrication and reasonability. The ammonia sensing properties of PANI/MWCNTs/MoS2 nanocomposite were investigated at room temperature. The experimental results exhibited excellent properties in terms of high response, fast response/recovery time as well as outstanding repeatability, which were greatly superior to the pure PANI, PANI/MWCNTs and PANI/MoS2 film counterparts. Finally, the potential ammonia-sensing mechanism of the PANI/MWCNTs/MoS2 nanocomposite was systematically discussed, which is attributed to the synergistic effect of the ternary nanomaterials and special interactions at p-n heterojunction.

Improved lithium-ion battery anode performance via multiple element approach

In this work, single (Co3O4), binary (Co3O4/ZnO) and ternary (Co3O4/ZnO/NiO) nanomaterials were successfully synthesized by Pechini method followed by a calcination step. Electrochemical lithium storage capabilities of the anode materials were studied. The results showed that the best capacity retention and lowest voltage hysteresis was achieved with ternary material. The ternary material showed a first cycle charge capacity of 649 mAh/g at 70 mA/g and maintained 83% of this capacity after 39 cycles. The results demonstrated the positive impact of multiple element strategy on the cycle life of anode materials.

Acetylene Gas-Sensing Properties of Layer-by-Layer Self-Assembled Ag-Decorated Tin Dioxide/Graphene Nanocomposite Film.

This paper demonstrates an acetylene gas sensor based on an Ag-decorated tin dioxide/reduced graphene oxide (Ag–SnO2/rGO) nanocomposite film, prepared by layer-by-layer (LbL) self-assembly technology. The as-prepared Ag–SnO2/rGO nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectrum. The acetylene sensing properties were investigated using different working temperatures and gas concentrations. An optimal temperature of 90 °C was determined, and the Ag–SnO2/rGO nanocomposite sensor exhibited excellent sensing behaviors towards acetylene, in terms of response, repeatability, stability and response/recovery characteristics, which were superior to the pure SnO2 and SnO2/rGO film sensors. The sensing mechanism of the Ag–SnO2/rGO sensor was attributed to the synergistic effect of the ternary nanomaterials, and the heterojunctions created at the interfaces between SnO2 and rGO. This work indicates that the Ag–SnO2/rGO nanocomposite is a good candidate for constructing a low-temperature acetylene sensor.

Ordered SnO nanoparticles in MWCNT as a functional host material for high-rate lithium-sulfur battery cathode

Lithium-sulfur battery has become one of the most promising candidates for next generation batteries, and it is still restricted due to the low sulfur conductivity, large volume expansion and severe polysulfide shuttling. Herein, we present a novel hybrid electrode with a ternary nanomaterial based on sulfur-impregnated multiwalled carbon nanotubes filled with ordered tin-monoxide nanoparticles (MWCNT-SnO/S). Using a dry plasma reduction method, a mechanically robust material is prepared as a cathode host material for lithium-sulfur batteries. The MWCNT-SnO/S electrode exhibits high conductivity, good ability to capture polysulfides, and small volume change during a repeated charge–discharge process. In situ transmission electron microscopy and ultraviolet–visible absorption results indicate that the MWCNT-SnO host efficiently suppresses volume expansion during lithiation and reduces polysulfide dissolution into the electrolyte. Furthermore, the ordered SnO nanoparticles in the MWCNTs facilitate fast ion/electron transfer during the redox reactions by acting as connective links between the walls of the MWCNTs. The MWCNT-SnO/S cathode with a high sulfur content of 70 wt.% exhibits an initial discharge capacity of 1,682.4 mAh·g–1 at 167.5 mA·g–1 (0.1 C rate) and retains a capacity of 530.1 mAh·g–1 at 0.5 C after 1,000 cycles with nearly 100% Coulombic efficiency. Furthermore, the electrode exhibits the high capacity even at a high current rate of 20 C.

Sequence‐Designed Peptide Nanofibers Bridged Conjugation of Graphene Quantum Dots with Graphene Oxide for High Performance Electrochemical Hydrogen Peroxide Biosensor

Motif‐designed peptide molecules have the unique property to form filamentous nanostructure and the ability to conjugate with other nanoscale building blocks such as graphene and nanoparticles to create functional nanomaterials. Here, the design of a novel functional peptide molecule is reported, which has the abilities to form peptide nanofibers (PNFs) and recognize with graphene quantum dots (GQDs) and graphene oxide (GO) nanosheet specifically. Based on the design of peptide sequence, the ternary GQD‐PNF‐GO nanohybrids are synthesized successfully. The created ternary GQD‐PNF‐GO nanohybrids are characterized by transmission electron microscopy and atomic force microscopy (AFM). To understand the formation mechanism of this ternary nanostructure, the interactions between GQD, PNF, and GO are further investigated by AFM‐based force spectroscopy. Moreover, it is found that the synthesized ternary GQD‐PNF‐GO nanohybrids show potential applications for high performance electrochemical hydrogen peroxide (H2O2) biosensor. This fabricated biosensor exhibits high sensitivity and selectivity, low detection limit, and wide linear range for sensing H2O2. It is believed that the strategies shown in this work such as the motif design of peptide and its self‐assembly on GO will benefit the further creation of functional binary and ternary nanomaterials, as well as the understanding of their self‐assembly and formation mechanisms.

Research on the Sol-Gel Method of Preparing Ternary Nano SiO<sub>2</sub>-Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> Materials

Tetraethyl orthosilicate (TEOS), butyl titanate [Ti (OBu)4] and aluminium isopropoxide were used as molecular precursor of ternary nanoSiO2-Al2O3-TiO2 materials. The influences of temperature and the dosage of compounds on the characteristic of ternary nanomaterials were investigated. Transmission electron microscopy (TEM), x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were employed to investigate the characteristics of the nanomaterials synthesized by the sol-gel method. In addition, the adsorption of nanomaterials for different kinds of surfactants was also studied. Results revealed that the influences of temperature, compounds dosages and water on the size of ternary nanomaterials had a significant impact. With the increase of ammonia dosage, the concentration of the OH- ion became higer, and system showed a faster reaction rate. The higer temperature of the system was, the larger size of the ternary nanomaterials was. Moreover, the higer tempreature woule also lead to divide into layer and precipitate. Optimal parameters can be chosen to prepare monodispersed ternary nanoSiO2-Al2O3-TiO2 materials. Results also showed that the surface characteristic of ternary nanoSiO2-Al2O3-TiO2 particles differed from nanosilica, which manifested in forms of the adsorption dosage of surfactants.

Electrochemical sensing platform for hydrogen peroxide using amorphous FeNiPtnanostructures

Amorphous ternary FeNiPt nanomaterials with tunable length are reported for constructing the electrochemical sensing platform, in which hydrogen peroxide (H2O2) is selected as a model target. It is found that amorphous FeNiPt nanostructures, in particular, the FeNiPt nanorods with large axial-ratio (FeNiPt-NRL) exhibit the enhanced electrocatalytic activity towards both the oxidation and reduction of H2O2. Meanwhile, the comparable corrosion potential Ecorr and lower corrosion current Icorr are observed at GC electrodes modified with FeNiPt-NRL, revealing the good stability of the FeNiPt-NRL surface. On the basis of these results, H2O2 is cathodically determined at glassy carbon (GC) electrodes with FeNiPt-NRL with relatively high selectivity at the appropriate potential of 0 V vs. Ag|AgCl. On the other hand, the sensitivity of the anodic H2O2 detection at the same electrode is achieved to be 2.45 mA cm−2 mM−1, which is 4-fold larger than that of the cathodic detection and those Pt nanoparticles-based H2O2 determination, and the detection limit is also developed to 40 nM. The dynamic linear range is broadened from 100 nM to 30 mM, which is wider than those H2O2 detection based on Pt nanoparticles and binary Pt alloys. In addition, electrochemical results show the high stability and good reproducibility for the present H2O2 sensor. The striking analytical performance combined with the intrinsic properties of amorphous FeNiPt nanomaterials provides a promising technique for the development of non-enzyme H2O2 and other molecule sensors with high sensitivity, broad dynamic linear range, long stability, and good reproducibility.

Fabrication, structural characterization and photoluminescence of single-crystalZnxCd1−xS zigzag nanowires

Large-scale synthesis of ternaryZnxCd1−xS zigzag nanowires was achieved in a one-step metal–organic chemical vapour deposition(MOCVD) process with co-fed single precursors of ZnS and CdS. Their morphologies, structuresand optical properties were characterized and confirmed by scanning electron microscopy,high-resolution transmission electron microscopy, x-ray spectroscopy, and photoluminescence. TheZnxCd1−xS zigzag nanowires are single crystalline, with axis [001], by changing the growth directionfrom to . Regarding the formation of zigzag nanowires, we suggest that the shear strainand slight fluctuation of the reaction conditions may be the major factors thatmake the nanowires change growth direction. In addition, because of the lowertemperature and versatility, this new fabrication method might present a new and facileway to form other ternary nanomaterials. Furthermore, the green emission ofthe nanowires may have potential applications in electronic/optical nanodevices.