Sb2Se3 Nanorods Research Articles

Sb2Se3 nanorods with N-doped reduced graphene oxide hybrids as high-capacity positive electrode materials for rechargeable aluminum batteries.

For substantially promoting the unexpected rechargeable capability induced from the dissolution of Sb2Se3 positive electrode materials in aluminum batteries, here a novel prototype of a cell assembled by a hybrid of single-crystalline Sb2Se3 nanorods and N-doped reduced graphene oxide (SNG) coupled with a modified separator has been developed. With this specific cell design, the hybrid positive electrode material exhibits a high discharge potential (∼1.8 V) with a considerably high initial discharge capacity of up to 343 mA h g-1 at a current density of 500 mA g-1. Owing to the alleviation of active material loss from the positive electrode, the cell having the modified separator exhibits much enhanced cycling stability. Besides, nitrogen-doping on the reduced graphene oxide is found to boost the active sites in SNG, and thus the cycling performance has been largely improved. The strategy used in this work offers a universal plateau for designing long-life cycle aluminum batteries.

Metal selenobenzoate complexes: Novel single source precursors for the synthesis of metal selenide semiconductor nanomaterials

Nanomaterials synthesis using single source precursors is a fascinating development in material science. The shape and size dependent properties offer countless opportunities for interesting discoveries, but also poses challenges to the scientific community to control the shape and size of these materials. Selenocarboxylate complexes are difficult to synthesize, due to the instability of selenocarboxylic acids. In this study, we have developed an efficient one-pot synthesis of the selenobenzoate ligand and its three new metal complexes, tris(selenobenzoato)antimony(III), tris(selenobenzoato)bismuth(III) and bis(selenobenzoato)dibutyltin(IV). The complexes were used as single source precursors to synthesize Sb2Se3 nanorods, Bi2Se3 and SnSe nanosheets by colloidal thermolysis using the hot injection method. The as-synthesized nanomaterials were characterized by p-XRD, TEM, SAED and HRTEM techniques. The complexes were synthesized by a facile method with high yields and are stable at room temperature for period of several months, We believe that the selenobenzoate complexes with other metals can also be synthesized by using our method and those complexes can be useful precursors for metal selenide thin films or nanoparticles.

One-Dimensional Sb2Se3 Nanorods Synthesized through a Simple Polyol Process for High-Performance Lithium-Ion Batteries

The good crystalline Sb2Se3 nanorods have been successfully synthesized through a simple polyol process. The detailed morphological and structural characterizations reveal that nanorods are composed of Sb2Se3 single crystals oriented along the [120] orientation; the tiny Sb2Se3 nanorods are found to display a higher crystallinity with respect to thick Sb2Se3 nanorods. The nanorods have been applied as anode materials for lithium-ion batteries, with tiny Sb2Se3 nanorod anodes delivering the relatively high discharge capacity of 702 mAh g−1 at 0.1 C and could maintain the capacity of 230 mAh g−1 after 100 cycles. A more stable cycling performance is also demonstrated on tiny Sb2Se3 nanorods, which is ascribed to their more pronounced one-dimensional nanostructure.

Novel single source precursor for synthesis of Sb2Se3 nanorods and deposition of thin films by AACVD: Photo-electrochemical study for water reduction catalysis

A new complex, tris(selenobenzoato)antimony(III) has been synthesized by a facile route and the structure determined by single crystal X-ray crystallography. The complex was used as a single source precursor to synthesize Sb2Se3 nanorods by the hot injection method whereas Sb2Se3 thin films were deposited on glass substrates by the Aerosol Assisted Chemical Vapour Deposition (AACVD) technique. The as synthesized nanorods and thin films were then characterized by powder X-ray diffraction, electron microscopy, Raman and UV/Vis spectroscopy. AACVD of the complex produced highly crystalline and pure Sb2Se3 thin films between 400 and 500 °C. The shape of Sb2Se3 crystallites are generally in the form of wires or thin plates, sometimes forming leaf-like structures uniformly spread on the entire substrate. The size and shape of these crystallites with their stoichiometry was found to be dependent on the deposition temperature. Sb2Se3 nanorods were tested for photo-electrochemical (PEC) water reduction catalysis. When simulated solar light was illuminated at the Sb2Se3/FTO surface, cathodic photocurrents were generated for H2 generation. At open circuit potential (OCP) photo-cathodic current generated with the Sb2Se3/FTO electrode was in the range of −44.8 to −52.1 μA·cm−2.

Adjusting the Anisotropy of 1D Sb2Se3 Nanostructures for Highly Efficient Photoelectrochemical Water Splitting

AbstractSb2Se3 has recently spurred great interest as a promising light‐absorbing material for solar energy conversion. Sb2Se3 consists of 1D covalently linked nanoribbons stacked via van der Waals forces and its properties strongly depend on the crystallographic orientation. However, strategies for adjusting the anisotropy of 1D Sb2Se3 nanostructures are rarely investigated. Here, a novel approach is presented to fabricate 1D Sb2Se3 nanostructure arrays with different aspect ratios on conductive substrates by simply spin‐coating Sb‐Se solutions with different molar ratios of thioglycolic acid and ethanolamine. A relatively small proportion of thioglycolic acid induces the growth of short Sb2Se3 nanorod arrays with preferred orientation, leading to fast carrier transport and enhanced photocurrent. After the deposition of TiO2 and Pt, an appropriately oriented Sb2Se3 nanostructure array exhibits a significantly enhanced photoelectrochemical performance; the photocurrent reaches 12.5 mA cm−2 at 0 V versus reversible hydrogen electrode under air mass 1.5 global illumination.

Thermally induced structural evolution and performance of Sb2Se3 films and nanorods prepared by an easy sputtering method

An easy method of preparing well-crystallized Sb2Se3 films and nanorods through magnetron sputtering was proposed, and their growth mechanism was examined. The microstructure, morphology, composition, and optical and electrical properties of the Sb2Se3 films depended strongly on the substrate temperature (Tsub). Sb2Se3 films prepared at > 250°C contained the orthorhombic phase without Sb2O3 phase owing to the high-purity vacuum environment. Well-crystallized Sb2Se3 films deposited at Tsub = 325°C showed compact grains with a bandgap of 1.23eV and a high absorption coefficient of 105cm−1 in the visible region. Photoelectrochemical measurements showed that Sb2Se3 films were p-type semiconductors with excellent photoresponse. A clear photovoltaic effect with a power conversion efficiency (PCE) of 3.35% was measured for the first time by using the sputtering Sb2Se3 films as absorbers in a photovoltaic solar cell. At Tsub = 375°C, highly uniform films with monodispersed Sb2Se3 nanorods were obtained. The preferential orientation of the Sb2Se3 crystals by self-organization was promoted by increasing Tsub. By using the Sb2Se3 nanorods as absorbers in a solar cell, good photoresponse and a PCE of 2.15% were achieved.

Sb2Se3 nanorods with length dependent photoresponses

The length effects on photoconductivity have been observed in Sb2Se3 nanorods with uniform diameter grown by a hot-injection polyol process. The phase formation and morphology evolution of Sb2Se3 nanorods were investigated by XRD and TEM analysis. By changing the reaction temperature from 150 °C to 250 °C, the sizes and aspect ratios of Sb2Se3 nanorods can be easily controlled, with an average length ranged from 0.6 μm to 3.2 μm. The length-controlled nanorods were directly used for fabricating prototype photodetectors to explore their length-dependence performances. A significant increase of photoresponse with length elongation has been observed, in which the optimal device displays a remarkable response to simulated solar light with a high switching “on/off” ratio of 320, short response/recovery times (0.15/0.16 s) and long-term durability. This length-dependence property on photodetectors can be considered as an important step to promote the performance of 1D Sb2Se3 nanomaterials.

A New rGO‐Overcoated Sb2Se3 Nanorods Anode for Na+ Battery: In Situ X‐Ray Diffraction Study on a Live Sodiation/Desodiation Process

Sodium ion batteries (SIBs) are a promising alternative to lithium ion batteries for a broader range of energy storage applications in the future. However, the development of high‐performance anode materials is a bottleneck of SIBs advancement. In this work, Sb2Se3 nanorods uniformly wrapped by reduced graphene oxide (rGO) as a promising anode material for SIBs are reported. The results show that such Sb2Se3/rGO hybrid anode yields a high reversible mass‐specific energy capacity of 682, 448, and 386 mAh g−1 at a rate of 0.1, 1.0, and 2.0 A g−1, respectively, and sustains at least 500 stable cycles at a rate of 1.0 A g−1 with an average mass‐specific energy capacity of 417 mAh g−1 and capacity retention of 90.2%. In situ X‐ray diffraction study on a live SIB cell reveals that the observed high performance is a result of the combined Na+ intercalation, conversion reaction between Na+ and Se, and alloying reaction between Na+ and Sb. The presence of rGO also plays a key role in achieving high rate capacity and cycle stability by providing good electrical conductivity, tolerant accommodation to volume change, and strong electron interactions to the base Sb2Se3 anode.

Controllable Synthesis and Properties of Sb₂Se₃ Nanorods Synthesized by Hot-Injection Method.

Antimony selenide (Sb₂Se₃) is an interesting p-type semiconductor with a proper bandgap for photovoltaic devices. In this work, Sb₂Se₃ nanorods with controllable length-width ratios were synthesized via hot-injection method, where selenium powder was used as selenium sources and oleylamine was selected as reducing agent and high-point solvent. X-ray diffraction (XRD) patterns and high resolution Transmission electron microscope (HRTEM) results demonstrate that nanorods are wellcrystallized single crystalline and grow along the [110] direction. The reaction temperatures were found to have a noticeable influence on the morphologies of Sb₂Se₃ nanorods. The growth mechanism of the nanorods was discussed based on scanning electron microscope (SEM) observations. Vis-NIR absorption spectra reveal that the bandgaps of nanorods were between 0.75 eV and 1.1 eV. Electrical conductivities in dark and light were also investigated.

Preparation of uniform Sb2Se3 nanorods by hot-injection polyol process and their application in photodetector

A facile, environment-friendly, low-cost and time-saving hot-injection process using triethylene glycol as solvent was developed to synthesize uniform and pure-phase Sb2Se3 nanorods with single crystalline structure. The crystal structure, morphology and chemical composition of the synthesized Sb2Se3 nanorods were characterized. The synthesized Sb2Se3 nanorods were used to prepare a photodetector and obtain excellent photoresponsive properties with a switching “on/off” ratio of 70 under 658nm irradiation (15.8mW/cm2) at a voltage of 3V. Moreover, the Sb2Se3-based photodetector displayed a good durability and fast photoresponsive property with response time of 64ms and decay time of 68ms. To our best knowledge, the photoresponsive time of the synthesized Sb2Se3-based photodetector is faster than that of previous reported Sb2Se3-based photodetector.

Antimony Selenide Nanorods Decorated on Reduced Graphene Oxide with Excellent Electrochemical Properties for Li-Ion Batteries

A promising anode material for lithium-ion batteries (LIBs) consisting of Sb2Se3 nanorods and reduced graphene oxide (rGO) sheets has been prepared by an effective solvothermal approach. The synergetic effect between Sb2Se3 nanorods and rGO matrix provides not only high conductivity paths and strong electron contact interface, but also alleviates the volume change of Sb2Se3 nanorods, resulting in excellent lithium-storage performance. When tested as an anode material for LIBs, a high capacity of 868.30 mAh g−1 can be retained after 100 cycles at 200 mA g−1. Even at 2000 mA g−1, a satisfactory capacity of 430.40 mAh g−1 after long 550 cycles can be delivered. Ex situ X-ray diffraction study suggests that the Sb2Se3/rGO composite follows the combined Li+ intercalation, conversion reaction and alloying reaction mechanism. These features suggest the Sb2Se3/rGO composite a viable choice for application as an anode material in high-performance LIBs.

Size control of 1D Sb2Se3 nanorods prepared by a facile mixed solvothermal method with tartaric acid assistance

Sb2Se3 can readily form long, 1D rod-shaped structures due to the intrinsic properties of orthorhombic Sb2Se3 crystals. Herein, short, 1D rod-shaped Sb2Se3 was synthesized by a facile mixed solvothermal method with tartaric acid (TA) assistance, and the synthetic mechanism is illustrated. Different sizes of 1D Sb2Se3 nanorods could be achieved by controlling the reaction temperature and using THF as a solvent to increase the reaction pressure. The formation of long, 1D rod-shaped Sb2Se3 when sodium tartrate was added instead of tartaric acid was explained by the coordination and dissociation equilibrium of antimony potassium tartrate. The effect of different amounts of TA on Sb2Se3 morphology was interpreted based on the precipitation–dissolution equilibrium of Sb2Se3. This study provides an effective method to control the sizes of Sb2Se3 nanorods.

Synthesis, Characterization, and Catalytic Performance of Sb2Se3 Nanorods

Antimony selenide has many potential applications in thermoelectric, photovoltaic, and phase-change memory devices. A novel method is described for the rapid and scalable preparation of antimony selenide (Sb2Se3) nanorods in the presence of hydrazine hydrate and/or permanganate at 40°C. Crystalline nanorods are obtained by the addition of hydrazine hydrate in a reaction mixture of antimony acetate and/or chloride and sodium selenite in neutral and basic media, while amorphous nanoparticles are formed by the addition of KMnO4 in a reaction mixture of antimony acetate/chloride and sodium selenite. The powder X-ray diffraction pattern confirms orthorhombic phase crystalline Sb2Se3 for the first and second reactions with lattice parameters a=1.120 nm, b=1.128 nm, and c=0.383 nm and amorphous Sb2Se3 for the third reaction. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM) images show the diameter of nanorods for the first and second reactions to be in the order of 100 nm to 150 nm and about 20 nm particles for the third reaction. EDX and XPS suggest that the nanorods are pure Sb2Se3. The UV-vis analysis indicates a band gap of 4.14 and 4.97 eV for the crystalline and amorphous Sb2Se3, respectively, corresponding to a blue shift. The photocatalytic study shows that the decolorization of Rhodamine in solution by nanoparticles is slightly greater than nanorods.

Facile preparation and enhanced photoelectrical performance of Sb2Se3 nano-rods by magnetron sputtering deposition

In this work, a simple and effective method for fabricating Sb2Se3 nano-rods films by magnetron sputtering Sb2Se3 alloy target at a substrate temperature of 375°C is proposed. The thermally induced regular shape and vertically arrayed nano-rods exhibits a well-crystallized structure with a preferred crystallographic orientation of (221) and a stable valence of Sb3+ and Se 2−. The obtained thin film has a band-gap of 1.32eV and a high absorption coefficient of 105cm−1 in visible region. The photo-electrochemical measurements show that the Sb2Se3 nano-rods are p-type semiconductors with an excellent photo-response. A photovoltaic solar cell using the Sb2Se3 nano-rods film as absorber has demonstrated and a clear photovoltaic effect with an encouraging power conversion efficiency of 2.11% can be achieved.

Polyol process synthesis of metal selenide nanomaterials and their photovoltaic application

A mixed solvent of monoethanolamine and thioglycolic acid is successfully used to dissolve Se powder to prepare a highly reactive and soluble Se solution at room temperature in air. The as-prepared Se solution is very stable for more than half a year without any observed precipitation even in air. We used the Se precursor solution to synthesize various metal selenide nanomaterials such as Sb2Se3 nanorods, CuSe nanoplates and CuInSe2 nanocrystals by using a facile and environmentally-friendly triethylene glycol process. The structure, morphology, chemical composition and optical properties of the synthesized metal selenide nanomaterials are characterized. Moreover, the CuInSe2 nanocrystals are used to prepare ethanol-based colloidal ink and then deposited thin films by a dip-coating process. The synthesized CuInSe2 nanocrystal thin films are annealed at 550 °C in a selenizing atmosphere. A power conversion efficiency of 2.65% has been achieved by using the CuInSe2 thin films after selenization as a light-absorbing layer under AM 1.5 illumination.

Structural Studies and Optical and Electrical Properties of Novel Gd3+‐Doped Sb2Se3 Nanorods

Gd3+‐doped Sb2Se3 nanorods were synthesized by coreduction method at 180°C and pH = 12 for 48 h. Powder XRD patterns indicate that the GdxSb2−xSe3 crystals (x = 0.00–0.04) are isostructural with Sb2Se3. The cell parameters a and b increase for Gd3+ upon increasing the dopant content (x), while c decreases. SEM images show that doping of Gd3+ ions in the lattice of Sb2Se3 results in nanorods. High‐resolution transmission electron microscopic (HRTEM) studies reveal that the Gd0.04Sb1.96Se3 is oriented in the [10‐1] growth direction. UV‐Vis absorption reveals mainly electronic transitions of the Gd3+ ions in doped nanomaterials. Emission spectra of doped materials show sharp emission band originating from f‐f transition 6P7/2→8S7/2 of the Gd3+ ions. The electrical conductance of Gd‐doped Sb2Se3 is higher than undoped Sb2Se3 and increases with temperature.

Spectroscopy of a single Sb2Se3 nanorod

In this paper, we present solvothermal methods to chemically synthesize Sb2Se3 nanorods using dialkyl diselenophosphate (dsep) complexes of antimony. Energy-dispersive X-ray analysis shows the products are phase pure. We have also studied the Raman and photoluminescence spectroscopy of a single Sb2Se3 nanorod with an average size of 60 nm in diameter and a length less than 1 μm. Techniques have been devised to immobilize and allocate a single nano-object on an electron beam (E-beam) patterned smart substrate with metallic coordination markers. This also overcomes the limitation of spatial resolution of conventional optical techniques (~1 μm) to perform optical spectroscopy on an individual nano-object less than 100 nm in size. Raman spectroscopy reveals that Sb2Se3 nanorods synthesized at a lower temperature contain a small amount of Sb2Se3. The broad linewidth observed in luminescence spectra from a single rod is attributed to the increasing number of surface defects, impurities, and dangle bonds attached on the surface as the nanoparticle size reduced to nanometer scale.

Electrical and optical properties of a single Sb2Se3 nanorod

AbstractIn this paper we present the methods to chemically synthesize the Sb2Se3 nanorods and study the electrical and optical properties of a single Sb2Se3 nanorod with an average size of 70 nm in diameter and a length of about 1 μm to 2 μm. The techniques we devised can immobilize and allocate a single nano-object on an electron beam (E-beam) patterned smart substrate. It can also overcome the limitation of the spatial resolution of conventional optical techniques (∼ 1 mm) to obtain optical spectroscopy in an individual nano-object less than 100 nm in size. We also demonstrate the techniques in using E-beam defined metallic coordination markers as electrodes to measure the conductance of a single Sb2Se3 nanorod.

Synthesis and characterization of Sb2Se3 nanorods

A hydrothermal reduction route was employed for the synthesis of Sb2Se3 semiconductor nanorods. The reaction temperature for the formation of Sb2Se3 nanorods should be above 130°C, otherwise impurities, such as Sb2O3 and unreacted Se, would exist. The role of hydrazine as both the reducing agent and the coordinator was also found to be crucial for the formation of the rod-like morphologies. The products were characterized by XRD, SEM, TEM, XPS, absorption spectroscopy and Raman spectroscopy.