Sb2 Se3 Research Articles

Understanding the Structure and Properties of Sesqui‐Chalcogenides (i.e., V2VI3 or Pn2Ch3 (Pn = Pnictogen, Ch = Chalcogen) Compounds) from a Bonding Perspective

A number of sesqui-chalcogenides show remarkable properties, which make them attractive for applications as thermoelectrics, topological insulators, and phase-change materials. To see if these properties can be related to a special bonding mechanism, seven sesqui-chalcogenides (Bi2 Te3 , Bi2 Se3 , Bi2 S3 , Sb2 Te3 , Sb2 Se3 , Sb2 S3 , and β-As2 Te3 ) and GaSe are investigated. Atom probe tomography studies reveal that four of the seven sesqui-chalcogenides (Bi2 Te3 , Bi2 Se3 , Sb2 Te3 , and β-As2 Te3 ) show an unconventional bond-breaking mechanism. The same four compounds evidence a remarkable property portfolio in density functional theory calculations including large Born effective charges, high optical dielectric constants, low Debye temperatures and an almost metal-like electrical conductivity. These results are indicative for unconventional bonding leading to physical properties distinctively different from those caused by covalent, metallic, or ionic bonding. The experiments reveal that this bonding mechanism prevails in four sesqui-chalcogenides, characterized by rather short interlayer distances at the van der Waals like gaps, suggestive of significant interlayer coupling. These conclusions are further supported by a subsequent quantum-chemistry-based bonding analysis employing charge partitioning, which reveals that the four sesqui-chalcogenides with unconventional properties are characterized by modest levels of charge transfer and sharing of about one electron between adjacent atoms. Finally, the 3D maps for different properties reveal discernible property trends and enable material design.

Chemical Vapor Deposition Growth of High Crystallinity Sb2 Se3 Nanowire with Strong Anisotropy for Near-Infrared Photodetectors.

Low-dimensional semiconductors have attracted considerable attention due to their unique structures and remarkable properties, which makes them promising materials for a wide range of applications related to electronics and optoelectronics. Herein, the preparation of 1D Sb2 Se3 nanowires (NWs) with high crystal quality via chemical vapor deposition growth is reported. The obtained Sb2 Se3 NWs have triangular prism morphology with aspect ratio range from 2 to 200, and three primary lattice orientations can be achieved on the sixfold symmetry mica substrate. Angle-resolved polarized Raman spectroscopy measurement reveals strong anisotropic properties of the Sb2 Se3 NWs, which is also developed to identify its crystal orientation. Furthermore, photodetectors based on Sb2 Se3 NW exhibit a wide spectral photoresponse range from visible to NIR (400-900 nm). Owing to the high crystallinity of Sb2 Se3 NW, the photodetector acquires a photocurrent on/off ratio of about 405, a responsivity of 5100 mA W-1 , and fast rise and fall times of about 32 and 5 ms, respectively. Additionally, owing to the anisotropic structure of Sb2 Se3 NW, the device exhibits polarization-dependent photoresponse. The high crystallinity and superior anisotropy of Sb2 Se3 NW, combined with controllable preparation endows it with great potential for constructing multifunctional optoelectronic devices.

Thermochromism from Ultrathin Colloidal Sb2 Se3 Nanowires Undergoing Reversible Growth and Dissolution in an Amine-Thiol Mixture.

Liquid-based thermochromics can be incorporated into an arbitrarily shaped container and provide a visual map of the temperature changes within its volume. However, photochemical degradation, narrow temperature range of operation, and the need for stringent encapsulation processes are challenges that can limit their widespread use. Here, a unique solution-based thermochromic comprising ultrathin colloidal Sb2 Se3 nanowires in an amine-thiol mixture is introduced. The nanowires undergo reversible growth and dissolution with repeated cycles of heating and cooling between 20 and 160 °C, exhibiting intense and contrasting color changes during these processes. Furthermore, the transition temperature in which a change in color first appears can be continuously tuned over a range larger than 100 °C by introducing controlled amounts of Sn2+ . The colloidal nanowire dispersion in the amine-thiol mixture retains its thermochromic properties over hundreds of temperature cycles, continuous heating at 80 °C over months, and shelf life of up to 2 years in an open container under ambient conditions. To illustrate its utility as a robust liquid thermochromic, the nanowire solution is coated onto standard filter paper and its uses as a rewritable surface by thermal scribing, as well as an inexpensive means of visualizing the temperature distribution of an anisotropically heated block are demonstrated.

Recent Advances in Earth-Abundant Photocathodes for Photoelectrochemical Water Splitting.

The conversion of solar energy into hydrogen through photoelectrochemical (PEC) water splitting is an attractive way to store renewable energy. Despite the intriguing concept of solar hydrogen production, efficient PEC devices based on earth-abundant semiconductors should be realized to compete economically with conventional steam reforming processes. Herein, recent milestones in photocathode development for PEC water splitting, particularly in earth-abundant semiconductors, in terms of new techniques for enhancing performance, as well as theoretical aspects, are highlighted. In addition, recent research into newly emerging low-cost p-type semiconductors in the PEC field, such as Cu2 BaSn(S,Se)4 and Sb2 Se3 , are scrutinized and the advantages and disadvantages of each material assessed.

Formation of Polypyrrole-Coated Sb2 Se3 Microclips with Enhanced Sodium-Storage Properties.

Antimony-based electrode materials with high specific capacity have aroused considerable interest as anode materials for sodium-ion batteries (SIBs). Herein, we develop a template-engaged ion-exchange method to synthesize Sb2 Se3 microclips, and the as-obtained Sb2 Se3 microclips are further in situ coated with polypyrrole (PPy). Benefiting from the structural and compositional merits, these PPy-coated Sb2 Se3 microclips exhibit enhanced sodium-storage properties in terms of high reversible capacity, superior rate capability, and stable cycling performance.

Highly Anisotropic Sb2 Se3 Nanosheets: Gentle Exfoliation from the Bulk Precursors Possessing 1D Crystal Structure.

2D materials, particularly those bearing in-plane anisotropic optical and electrical properties such as black phosphorus and ReS2 , have spurred great research interest very recently as promising building blocks for future electronics. However, current progress is limited to layered compounds that feature atomic arrangement asymmetry within the covalently bonded planes. Herein, a series of highly anisotropic nanosheets (Sb2 Se3 , Sb2 S3 , Bi2 S3 , and Sb2 (S, Se)3 ), which are composed of 1D covalently linked ribbons stacked together via van der Waals force, is introduced as a new member to the anisotropic 2D material family. These unique anisotropic nanosheets are successfully fabricated from their polymer-like bulk counterparts through a gentle water freezing-thawing approach. Angle-resolved polarized Raman spectroscopy characterization confirms the strong in-plane asymmetry of Sb2 Se3 nanosheets, and photodetection study reveals their high responsivity and anisotropic in-plane transport. This work can enlighten the synthesis and application of new anisotropic 2D nanosheets that can be potentially applied for future electronic and optoelectronic devices.

High thermoelectric performance in Te-free (Bi,Sb)2Se3via structural transition induced band convergence and chemical bond softening

In Te-free (Bi,Sb)2Se3, structural transition induced electronic band convergence and intensified phonon scattering triple the thermoelectricZTto 1.0.

Fixed Aspect Ratio Rod-to-Rod Conversion and Localized Surface Plasmon Resonance in Semiconducting I-V-VI Nanorods.

Fixed-aspect-ratio rod-to-rod conversion of binary V-VI Sb2 Se3 to ternary I-V-VI Cu3 SbSe3 semiconducting nano structures is reported. Capturing the inter mediate products, the insight mechanisms of the ion-diffusion process for the structural transformation are established. The final ternary structure shows localized surface plasmonresonance-induced absorption in the near-infrared regions.

Sb2Se3‐Sensitized Inorganic–Organic Heterojunction Solar Cells Fabricated Using a Single‐Source Precursor

The photovoltaic performance of Sb2 Se3 -sensitized heterojunction solar cells, which were fabricated by a simple deposition of Sb2 Se3 on mesoporous TiO2 by an approach that features multiple cycles of spin coating with a single-source precursor solution and thermal decomposition, is reported. Poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothioadiazole)] was used as the hole-transporting material. The most efficient cell exhibited a short-circuit current density of 22.3 mA cm(-2) , an open-circuit voltage of 304.5 mV, and a fill factor of 47.2 %, yielding a power conversion efficiency of 3.21 % under standard test conditions (irradiation of 1000 W m(-2) , air mass=1.5 G). The results of this study imply that the developed approach has a high potential as a simple and effective route for the fabrication of efficient and inexpensive solar cells.

Single step electrochemical synthesis of Sb2Se3 thin films: effect of molarities of precursor solution

In the present investigation, we have successfully synthesized polycrystalline Sb2Se3 thin films by single-step electrochemical method. Effect of concentration of precursor solution on structural, morphological, optical, and wettability properties by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), optical absorption, and contact angle measurement have been investigated. It is evident from XRD pattern that Sb2Se3 thin films are polycrystalline having orthorhombic crystal structure. Also, as precursor concentration increases the diffraction peak intensity also increases. Scanning electron micrographs reveal that the increase in precursor concentration causes the formation of soap foam like microstructure which is spread in the form of ellipsoids over whole substrate surface. The optical band gap decreases from 1.49 to 1.35 eV and contact angle decreases from 40° to 13°, i.e., the surface of Sb 2Se3 thin films converts from hydrophilic to superhydrophilic nature due to increase in precursor concentration. In addition, the holographic interferometric properties have been studied. The thickness, stress to substrate and deposited mass of the thin films is determined using double exposure holographic interferometry (DEHI) technique.

Theoretical and experimental study of the conduction mechanism in Sb2 Se3 alloy

To understand the nature of Sb2 Se3 semiconductor as a bulk sample, the X-ray diffraction study was carried out to identify the sample structure. Dc and ac electrical properties measured in the temperature range 290–370 K, and frequency range 102–105 Hz were the subject of the present work. Properties such as dielectric constant ζ\, loss function tanδ, and electrical conductivities σac as a function of both frequency and temperature are reported. Different models of electrical conduction in semiconductor materials have been used to explain the observed results. A trail has been made to correlate the results of this paper with the average heat of atomization H S and the average coordination number M. The experimental and theoretical investigation is in accordance with Liang criterion.

Deposition of chalcogenide thin films by solution growth technique on polymer surfaces

Chemical methods for deposition of thin films of Bi2S3, Bi2Se3, CdS and CdSe, T1S and T1Se, ZnS, ZnSe, NiS and NiSe, Sb2 Se 3, CoS, CoSe on polymer substrates have been developed. Polymer substrates have been activated by oxidation with KMnO4 solution and K2S208 with Ag + followed by washing with NH:-NH2, H2 SO4. Sulphides and selenides have been deposited with the use of triethanolamine, thiourea, thioacetamide, selenosulphate and metal salts in alkaline medium. Polymer substrates are polyacrylates, polystyrene, polyesters, polyolefins, polycarbonates. Semiconductor chalcogenide thin films have received major attention in recent years because of their application in device fabrications [1]. A chemical process for the preparation of thin films offers the advantages of economy, convenience and the ability to deposit large areas. Various chalcogenide thin films, for example Bi2S 3 [2], Bi2Se 3 [3], [CdS] and CdSe [4], T1S [5], T1Se [6], ZnS [7], ZnSe [8], [NiS] and NiSe [9], Sb2 Se3 [10], CoS [11], CoSe [12] have been prepared by solution growth technique. Pramanik et al. [12] found that triethanolamine is a potential complexing agent for deposition of thin films. All these films were deposited on glass substrate. This letter describes the deposition of thin films of chalcogenides on polymer substrates. Deposition of chalcogenide thin films on polymer substrates by a solution growth technique has not been reported previously. We describe here the technique for deposition of metal chalcogenide thin films by a solution growth technique on polymer substrates