Sb2S3 Nanoparticles Research Articles

A simple method for preparing Sb2S3/short-cut carbon fiber foam for the electrocatalytic degradation of dyes

The unstarched short-cut carbon fiber (SCF) foam modified with Sb2S3 nanoparticles (Sb2S3/SCF foam) was synthesized by melamine foam as a template to apply in electro-degradation of methyl orange (MO) and a mixture of dyes. This process takes full advantage of the self-supported 3D SCF foam's mechanical stability and electrical conductivity while preventing the aggregation of unstarched SCF and Sb2S3 nanoparticles. The in-situ deposition and good dispersion of Sb2S3 nanoparticles expose catalytic active sites synergy with stable free-standing 3D SCF foam resulting in efficient degradation capability. The morphology, composition, structure, and hydrophilicity of Sb2S3/SCF foam were analyzed using SEM, EDS, XPS, XRD, Raman, PL, BET and contact angle tests. The Sb2S3/SCF foam is highly effective for degrading MO, with a degradation rate of 97.92 % achieved in just 4 hours at 2.4 V (vs. SCE). Additionally, it could simultaneously degrade mixed dyes including methyl orange (MO), crystal violet (CV), and methylene blue (MB) within 5 hours, achieving complete fade. Furthermore, the Sb2S3/SCF foam also possesses desirable features for large-scale practical applications and recycling in dye degradation.

Amorphous and crystalline Sb2S3 nanoparticles embedded in N/S co-doped carbon as anodes for potassium-ion batteries

Antimony trisulfide (Sb2S3) has emerged as a promising anode candidate for potassium-ion batteries (PIBs) owing to its low cost and high theoretical specific capacity. However, its large volume expansion upon K+ storage and sluggish kinetics result in poor cycling performance and rate capability. To address these challenges, rational structural design is highly desirable. Herein, we report the synthesis of amorphous and crystalline Sb2S3 nanoparticles embedded in N/S co-doped carbon composites (a-Sb2S3@NSC and c-Sb2S3@NSC) via a facile organic coating combined with subsequent carbonization and sulfidation processes. When used as a PIBs anode material, a-Sb2S3@NSC exhibits a high discharge specific capacity of 415.6 mAh g−1 after 50 cycles at 200 mA g−1 and a stable rate capability (224.8 mAh g−1 at 2 A g−1), which remarkably outperforms that of the c-Sb2S3@NSC with inferior specific capacity (311.5 mAh g−1) and poor rate capability (67.7 mAh g−1). The amorphous structure of Sb2S3 nanoparticles in a-Sb2S3@NSC provides abundant defects and structural disorder, which reduces the entropy energy and activation barrier associated with K+ incorporation, effectively facilitating the transport and storage of K+. Moreover, the synergistic interactions between amorphous Sb2S3 nanoparticles and N/S co-doped carbon can effectively improve the electron/ion reaction kinetics and buffer volume variations, thus leading to superior potassium storage performances.

Staggered band alignment – direct Z-scheme for photocatalytic activity in Stibnite/rGO layered nanohybrids

Type-II staggered band aligned layered nanohybrids (LNHs) satisfy the unique characteristics required for photocatalysts. Here, the spin-assisted layer-by-layer deposition (SA-LBL) of stibnite/reduced graphene oxide (Sb2S3/rGO) LNHs are fabricated and their structural, morphological, electrical, and optical properties are reported. From the FESEM analysis, it was found that with increasing rGO content, the morphology of Sb2S3 nanoparticles changed from the granular to nanorods which might be due to Ostwald ripening or microstructural coarsening effect. Further, Raman spectroscopy proves that the B1 g and Ag of Sb2S3 decrease by the addition of rGO mainly due to the electron-phonon interaction. Based on the estimation of valence band edge and conduction band edge of Sb2S3/rGO LNHs using X-ray photoelectron spectroscopy and optical studies, we propose that the interface in Sb2S3/rGO LNHs is a type-II staggered band alignment Direct Z-scheme. The increased spatial charge separation and carrier lifetime of Sb2S3/rGO LNHs materials results in opening a new pathway to explore and extend their applications as photocatalysts.

Design of novel Sb2S3/Polythiophene heterojunction for efficient adsorption and methanol sensing

Eliminating micropollutants in trace concentrations in water bodies is crucial and challenging due to their persistent and bioactive characteristics. Due to these characteristics, their detection and removal pose a challenge to the conventional removal methods and to the health of the community. To effectively remove the pollutants, it requires the design and development of an efficient technique compared to the conventional techniques. The design of highly efficient methanol sensor and the adsorption of micropollutants by a heterojunction involving Sb2S3 and polythiophene (PTh) looks promising. The adsorption study was targeted on RhB dye whereas methanol was targeted to sensing application. Sb2S3 nanoparticles was synthesized by hydrothermal methods and incorporated into thiophene solution during chemical oxidative polymerization of thiophene. The heterojunction was applied to remove RhB dye through the adsorption process. Freundlich isotherm model and Langmuir isotherm model were used to study the adsorption of RhB. The higher adsorption capacity was found in case of Sb2S3/PTh is 99.8 mg g−1, and the rate constant (K2) was found to be 0.0206 min−1. The catalysts follows the pseudo-first and second order kinetics in the removal of RhB dye. The rate constant for adsorption k1 is 0.1347 min−1 and the rate constant for diffusion is 0.297 min−1. Moreover, the PTh/Sb2S3 shows an effective methanol sensing up to 0.7 mM and the current response at 0.6756 V of the oxidation peaks shows the presence of methanol.

Spatially Confined in Situ Formed Sodiophilic-Conductive Network for High-Performance Sodium Metal Batteries.

The sodium (Na) metal anode encounters issues such as volume expansion and dendrite growth during cycling. Herein, a novel three-dimensional flexible composite Na metal anode was constructed through the conversion-alloying reaction between Na and ultrafine Sb2S3 nanoparticles encapsulated within the electrospun carbon nanofibers (Sb2S3@CNFs). The formed sodiophilic Na3Sb sites and the high Na+-conducting Na2S matrix, coupled with CNFs, establish a spatially confined "sodiophilic-conductive" network, which effectively reduces the Na nucleation barrier, improves the Na+ diffusion kinetics, and suppresses the volume expansion, thereby inhibiting the Na dendrite growth. Consequently, the Na/Sb2S3@CNFs electrode exhibits a high Coulombic efficiency (99.94%), exceptional lifespan (up to 2800 h) at high current densities (up to 5 mA cm-2), and high areal capacities (up to 5 mAh cm-2) in symmetric cells. The coin-type full cells assembled with a Na3V2(PO4)3/C cathode demonstrate significant enhancement in electrochemical performance. The flexible pouch cell achieves an excellent energy density of 301 Wh kg-1.

Mathematical modelling based on deposition parameters for optical band gap estimation of Sb2S3 thin films

A mathematical prediction model was developed to predict the band gap of Sb2S3 films based on the synthesis parameters. For the optimization of process parameters, a chemometric optimization approach was used instead of the traditional method. The band gaps of chalcogenide films were measured between 1.68 eV and 1.98 eV. The developed model was able to predict the band gap of the optimized Sb2S3 sample, measured as 1.71 eV, as 1.77 eV. The mathematical model achieved the band gap prediction of both the optimized Sb2S3 film and the test sample with a relative error of 3.51% and 2.23%, respectively. The data revealed that the developed model could reliably predict the band gap of Sb2S3 nanoparticles with a relative error of less than 5%. These findings may provide a significant advantage in nanoscale applications in terms of better understanding the predictability of the band gap of Sb2S3 films prior to synthesis.

Amorphous non-doped and Se-, Cu-, and Zn-doped Sb2S3 nanoparticles prepared by a hot-injection method: bandgap tuning and possible observation of the quantum size effect

Amorphous, non-doped, and copper- and selenium-doped Sb2S3 nanoparticles were synthesized by a hot-injection method. Zinc-doped Sb2S3 nanoparticles were prepared for the first time using the same approach. Electron microscopy revealed that spherical nanoparticles of 1–4 nanometers aggregated into larger spherical clusters. Introducing dopants into the Sb2S3 structure neither influenced the samples’ spherical morphology nor their sizes. The presence of the dopants (Cu, Se, or Zn) was confirmed by energy dispersive X-ray (EDX) and, in the case of Zn, also by inductively coupled plasma-mass spectrometry (ICP-MS). The X-ray powder diffraction (XRPD) patterns of the non-doped and doped samples imply an amorphous structure. Crystalline Zn-doped Sb2S3 revealed defined peaks from only the Sb2S3 phase, indicating successful doping. Diffuse reflectance spectroscopy (DRS) revealed high optical bandgap energies (2.03–2.12 eV) compared to the values (1.6–1.7 eV) for large non-doped and doped particles obtained at 240 °C, which might be attributed to a quantum size effect. X-ray photoelectron spectroscopy (XPS) revealed a phase without any impurities for the undoped and characteristic peaks for copper, selenium, and zinc Auger for the doped samples. XPS valence band confirm for the Zn-doped particles a shift towards lower binding energy compared to the non-doped samples, indicating successful doping. Photoluminescence (PL) measurements show that embedding Zn into the Sb2S3 host lattice suppresses the wide luminescence band related to intrinsic vacancy defects. Narrow peaks at 1.7–2.4 eV were found to be associated with singlet excitons. The energy dependence of the light emission on the synthesized nanoparticles’ size suggests quantum confinement.

Ultra-fine Sb2S3 particles encapsulated in activated-carbon: A high-performance anode for Li-ion batteries

The low electronic conductivity and severe volume change hinder the commercialization of Sb2S3 anode, despite many efforts have been made to improve its electrochemical properties in the past decades. Many of these methods are complicated and different kinds of chemicals are required. Herein, a facile high-temperature melting method was employed to prepare high-performance Sb2S3 anode with nanosizing bulk natural stibnite and wrapping activated carbon. The activated carbon can provide nano-pores that absorb the molten Sb2S3. This structure can not only promote electronic conductivity but also provide accommodation for the volume change of Sb2S3 nanoparticles. More importantly, compared to other methods such as the hydrothermal method, the advantage of this method is that natural stibnite (95 wt% Sb2S3) was directly used as the Sb2S3 source without other synthetic or purification processes. Benefiting from these merits, the Sb2S3 composite anode exhibits good cyclic stability and excellent rate property, which delivers a high capacity of over 450 mAh g−1 even at a current density of 5 A g−1, proving that the Sb2S3 composite can serve as a promising anode for advanced lithium-ion batteries.

The Third-Order Nonlinear Optical Properties of Sb2S3/RGO Nanocomposites

Antimony sulfide/reduced graphene oxide (Sb2S3/RGO) nanocomposites were synthesized via a facile, one-step solvothermal method. XRD, SEM, FTIR, and Raman spectroscopy were used to characterize the uniform distribution of Sb2S3 nanoparticles on the surface of graphene through partial chemical bonds. The third-order nonlinear optical (NLO) properties of Sb2S3, RGO, and Sb2S3/RGO samples were investigated by using the Z-scan technique under Nd:YAG picosecond pulsed laser at 532 nm. The results showed that pure Sb2S3 particles exhibited two-photon absorption (TPA), while the Sb2S3/RGO composites switched to variable saturated absorption (SA) properties due to the addition of different concentrations of graphene. Moreover, the third-order nonlinear susceptibilities of the composites were also tunable with the concentration of the graphene. The third-order nonlinear susceptibility of the Sb2S3/RGO sample can achieve 8.63 × 10−12 esu. The mechanism for these properties can be attributed to the change of the band gap and the formation of chemical bonds supplying channels for photo-induced charge transfer between Sb2S3 nanoparticles and the graphene. These tunable NLO properties of Sb2S3/RGO composites can be applicable to photonic devices such as Q-switches, mode-locking devices, and optical switches.

Ultrafine Sb2S3@carbon-nanofibers for fast and stable sodium storage

Sb2S3 has great theoretical capacity (946 mAh g−1), suitable working potential, and relatively low cost, and it has attracted attention as a potential anode material for sodium-ion batteries. However, the tardy diffusion of sodium ions and significant volume expansion hinder their practical application in sodium ion batteries. In this study, we encapsulated Sb2S3 nanoparticles in porous carbon nanofibers (CNFs) using electrospinning and gas vulcanization. The unique porous fiber structure and ultrafine Sb2S3 nanoparticles effectively improved diffusion speed and volume expansion of sodium ions, and they showed fast sodium-ion storage capacity and excellent cycle stability. The Sb2S3@CNFs used as the anode of a sodium-ion battery exhibited a remarkably reversible specific capacity of 151.3 mAh g−1 at 10 A g−1 for 500 cycles. A full cell assembled with Sb2S3@CNFs and Na3V2(PO4)3 (NVP) showed a reversible specific capacity of 283 mAh g−1 at 0.2 A g−1 after 100 cycles. Therefore, Sb2S3@CNFs has an excellent practical application in sodium-ion batteries owing to its simple synthesis method, excellent electrochemical performance, and suitable reaction potential.

Amorphous Non-Doped and Se, Cu, and Zn-Doped Sb2s3 Nanoparticles Prepared by a Hot-Injection Method: Bandgap Tuning and Possible Observation of the Quantum Size Effect

Amorphous Non-Doped and Se, Cu, and Zn-Doped Sb2s3 Nanoparticles Prepared by a Hot-Injection Method: Bandgap Tuning and Possible Observation of the Quantum Size Effect

Boost the cyclability and Na+ diffusion kinetics of Sb2S3 anode by CNTs cross-linking N-doped carbon matrix

Antimony sulfides exhibit a tremendous potential owing to the high theoretical specific capacity from multiple redox storage mechanisms for sodium-ion batteries (SIBs). However, these bottlenecks, including low electrical conductivity, poor ionic diffusion kinetics, and severe volume expansion, still restrict the development of antimony sulfide as SIBs anodes. Meanwhile, in view of long-term interests and practical application, the cost-efficient preparation methods become an imminent challenge to the advancement of high-performance SIBs anodes. Here, a novel three-step strategy, composed of co-precipitation, heat reduction processes, and sulfation conversion, was utilized to construct a “reinforced concrete” architecture, in which Sb2S3 nanoparticles embedded in N-doped carbon matrix (NC) modified by carbon nanotubes (CNTs), denoted as Sb2S3/CNTs/NC. As the “cement block”, the N-doped 3D carbon matrix can promote the electron migration and reduce the aggregation of active materials upon cycling. In terms of “rebars” (i.e., 1D CNTs) for ensuring the anode integrality during incessant sodiation/de-sodiation processes, they function as binders and stabilizers, which intimately cross-link with Sb2S3 nanoparticles and carbon matrix, accommodate the volume change, and maintain the fast transfer of electron transfer inside the whole composite. Benefiting from these merits of the hierarchical structure (i.e., 3D NC and 1D CNTs), as an anode for SIBs, Sb2S3/CNTs/NC demonstrates an improved sodium storage capability with an initial specific capacity of 770.80 mAh g−1 at 0.1 A g−1 and a superior initial coulombic efficiency (ICE) of 79.90%. Moreover, even at a high current density of 1.0 A g−1, a reversible capacity of 313.54 mAh g−1 can be delivered after 350 long cycles, indicating the stable cyclicity. The Sb2S3/CNTs/NC with designed construction and enhanced electrochemical performance could provide a new perspective on low-cost, time-saving, and exercisable synthesis approach for high-performance sulfide-based anodes.

Interfacial Covalent Bonding Endowing Ti3 C2 -Sb2 S3 Composites High Sodium Storage Performance.

Antimony sulfide is attracting enormous attention due to its remarkable theoretical capacity as anode for sodium-ion batteries (SIBs). However, it still suffers from poor structural stability and sluggish reaction kinetics. Constructing covalent chemical linkage to anchor antimony sulfide on two-dimension conductive materials is an effective strategy to conquer the challenges. Herein, Ti3 C2 -Sb2 S3 composites are successfully achieved with monodispersed Sb2S3 uniformly pinned on the surface of Ti3 C2 Tx MXene through covalent bonding of Ti-O-Sb and S-Ti. Ti3 C2 Tx MXene serves as both charge storage contributor and flexible conductive buffer to sustain the structural integrity of the electrode. Systematic analysis indicates that construction of efficient interfacial chemical linkage could bridge the physical gap between Sb2S3 nanoparticles and Ti3 C2 Tx MXene, thus promoting the interfacial charge transfer efficiency. Furthermore, the interfacial covalent bonding could also effectively confine Sb2S3 nanoparticles and the corresponding reduced products on the surface of Ti3 C2 Tx MXene. Benefited from the unique structure, Ti3 C2 -Sb2 S3 anode delivers a high reversible capacity of 475 mAh g-1 at 0.2 A g-1 after 300 cycles, even retaining 410 mAh g-1 at 1.0 A g-1 after 500 cycles. This strategy is expected to shed more light on interfacial chemical linkage towards rational design of advanced materials for SIBs.

Structural, morphological, optical, and electronic properties of amorphous non-doped and I and Sn doped Sb2S3 nanoparticles

Amorphous non-doped, iodine- and tin-doped Sb2S3 nanoparticles were prepared via the hot-injection method. HRTEM of amorphous undoped and doped samples revealed the formation of spherical nanoparticles of 20–50 nm diameter aggregated into clusters in the size of 100–200 nm. EDX analysis indicated the presence of desired elements in all observed samples. The bandgaps of non-doped and doped samples were determined from the reflectance spectra, and variations of the bandgaps, even small ones, are insufficient indications of doping. These uncertainties are further clarified by investigating crystalline undoped and doped samples in addition to the amorphous ones. XRPD results of the amorphous samples confirmed the amorphous structure, while Le Bail refinements of the crystalline samples show well-defined peaks from only the Sb2S3 phase, indicating a successful doping process. XPS measurements revealed that the phase of the undoped sample is free of impurities and that 3 d peaks of iodine and tin in the doped samples are present. The XPS valence bands shifted towards higher (I) or lower (Sn) binding energies compared to the undoped samples for both amorphous and crystalline samples, which is an additional support that incorporation of dopant ions in the Sb2S3 lattice took place.

Revealing the formation mechanism and band gap tuning of Sb2S3 nanoparticles.

Sb2S3 is a promising nanomaterial for application in solar cells and in the fields of electronics and optoelectronics. Herein, Sb2S3 nanoparticles were prepared via the hot-injection approach. In contrast to earlier work, the reaction temperature was decreased to 150 °C so that the reaction was slowed down and could be stopped at defined reaction stages. Thereby, the formation mechanism of the nanomaterial and the associated kinetics could be revealed. Based on morphological and structural analyses, it is suggested that seed particles (type 0) formed immediately after injecting the antimony precursor into the sulfur precursor. These seeds fused to form amorphous nanoparticles (type I) that contained a lower percentage of sulfur than that corresponding to the expected stoichiometric ratio of Sb2S3. The reason for this possibly lies in the formation of an oxygen- or carbon-containing intermediate during the seeding process. Afterward, the type I nanoparticles aggregated into larger amorphous nanoparticles (type II) in a second hierarchical assembly process and formed superordinate structures (type III). This process was followed by the crystallization of these particles and a layer-like growth of the crystalline particles by an Ostwald ripening process at the expense of the amorphous particles. It was demonstrated that the kinetic control of the reaction allowed tuning of the optical band gap of the amorphous nanoparticles in the range of 2.2–2.0 eV. On the contrary, the optical band gap of the crystalline particles decreased to a value of 1.7 eV and remained constant when the reaction progressed. Based on the proposed formation mechanism, future syntheses for Sb2S3 particles can be developed, allowing tuning of the particle properties in a broad range. In this way, the selective use of this material in a wide range of applications will become possible.

ZIF-8 supported Sb2S3 fabrication carbon coating nanocomposite for dopamine sensor application

A ZIF-8 supported Sb2S3 fabrication carbon coating ZnS-Sb2S3 nanocomposite was synthesized with the template of zeolitic imidazolate framework (ZIF), through by the introduction of resorcinol-formaldehyde (RF) organic polymer to establish carbon layer, and by vulcanization process and metal-ion exchange reaction. The morphology and structural characteristics of carbon coating ZnS-Sb2S3 were investigated by X-ray diffraction spectroscopy, Raman spectra, X-ray photoelectron spectroscopy, Scanning electron microscopy and Transmission electron microscopy. Evidence indicated the nanocomposite has a polygonal structure with ZnS as core, Sb2S3 as inner shell, carbon layer coating as outer shell. This material was employed to prepare an electrode detected DA sensor; and its electrochemical impedance properties exhibited that carbon layer coating Sb2S3 nanoparticles can greatly improve the conductivity of nanocomposite. The proposed sensor showed some outstanding electrocatalytic performances, including a linear range from 0.2 to 3.1 μM, 3.1 to 711.1 μM, and a low detection limit of 0.6 μM and an excellent sensitivity of 458.3 and 184.6 μA mM−1 cm−2. Therefore, the carbon coating ZnS-Sb2S3 nanocomposite can be an effective electrode-modifying material that can be promisingly used in other electrochemical applications, and this method of preparing nanomaterials offer a novel perspective for electrochemical design the of other nanostructured systems.

Solar-light-driven photocatalysis by Sb2S3/carbon based composites towards degradation of noxious organic pollutants

Heterojunction photocatalysts are quite appealing for the effective removal of pollutants. Herein, we compare the photocatalytic dye degradation of Rhodamine-B (RhB) using pristine Sb2S3 nanoparticles (Sb2S3-NPs), Sb2S3-NPs anchored onto reduced graphene oxide (Sb2S3/rGO), and Sb2S3-NPs coated with porous carbon spheres (Sb2S3@PCS) as heterojunction photocatalysts. The successful fabrication of Sb2S3/C based heterogeneous photocatalysts was confirmed by XRD, FTIR, and Raman spectroscopy. The morphological studies revealed the formation of ~150–500 nm Sb2S3 nanoparticles wrapped with rGO sheets or encapsulated within ~65 nm thick porous carbon spheres. BET surface area analyses disclose that incorporating rGO and PCS improves the sp. surface area and favorable surface properties for effective RhB degradation. The UV–Vis DRS and PL showed that the heterojunction composites had narrow bandgap (~1.6–1.8 eV) and a suppressed recombination rate of photo-generated charge carriers exhibiting excellent photocatalytic activity compared to Sb2S3-NPs. Sb2S3/rGO and Sb2S3@PCS demonstrated RhB degradation-efficiency of ~89% (rate constant~ 0.013 min−1) and 77.65% (0.0091 min−1) after 150 min sunlight irradiation. The effects of catalyst concentration and pH (correlated with pHpzc) on the photodegradation were also examined. The enhanced photocatalytic performance of heterojunction photocatalysts could be ascribed to e−-excitation from the valence to conduction band, and facile electron mediator of π-conjugated porous carbon for Sb2S3/rGO and Sb2S3@PCS, respectively. The efficient photodegradation of colorless thiamethoxam pollutant confirmed indirect photocatalysis. The Sb2S3/rGO composite exhibited ~64% efficiency (rate constant~0.0056 min−1) whereas the Sb2S3@PCS maintained ~62% efficiency (rate constant~0.0064 min−1). Overall, the present study shows that Sb2S3/C-based heterogeneous photocatalysts are promising for wastewater treatment.

Microwave-Assisted Synthesis of Bi2S3 and Sb2S3 Nanoparticles and Their Photoelectrochemical Properties.

Bi2S3 and Sb2S3 nanoparticles were prepared by microwave irradiation of single-source precursor complexes in the presence of ethylene glycol as a coordinating solvent. The as-synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX), photoluminescence (PL), and UV–vis near-infrared (NIR) spectroscopy. Their electrochemical potential was examined in [Fe(CN)]4–/[Fe(CN)]3– by cyclic and square wave voltammetry (CV and SWV) and electrochemical impedance spectroscopy (EIS). GCEBi2S3 and GCESb2S3 exhibit promising electrochemical performance and a higher specific capacitance of about 700–800 F/g in [Fe(CN)]4–/[Fe(CN)]3. Thin films of Bi2S3 and Sb2S3 were successfully incorporated in the fabrication of solar cell devices. The fabricated device using Bi2S3 (under 100 mW/cm2) showed a power conversion efficiency (PCE) of 0.39%, with a Voc of 0.96 V, a Jsc of 0.00228 mA/cm2, and an FF of 44%. In addition, the device exhibits nonlinear current density–voltage characteristics, indicating that Bi2S3 was experiencing a Schottky contact. The Sb2S3-based solar cell device showed no connection in the dark and under illumination. Therefore, no efficiency was recorded for the device using Sb2S3, which indicated the ohmic nature of the film. This might be due to the current leakage caused by poor coverage. The nanoparticles were found to induce similar responses to the conventional semiconductor nanomaterials in relation to photoelectrochemistry. The present study indicates that Bi2S3 and Sb2S3 nanoparticles are promising semiconductor materials for developing optoelectronic and electrochemical devices as the films experience Schottky and Ohmic contacts.

Elucidating the role of graphene and porous carbon coating on nanostructured Sb2S3 for superior lithium and sodium storage

Antimony sulfide (Sb2S3) is a promising anode for alkali metal ion batteries owing to its high theoretical specific capacity derived from sequential conversion and alloying reactions with lithium/sodium. However, volume variance during (de)lithiation/(de)sodiation complemented with sluggish reaction kinetics leads to severe capacity decay and cycle instability. Carbon in various forms has been explored with Sb2S3 to absorb the volumetric strain by rationale materials and electrode design. However, identifying the suitable carbon composite structure for improved electrochemical performance in lithium-ion and sodium-ion batteries remains a subject of investigation. The present work sheds light on the difference between lithium and sodium storage behavior in Sb2S3/carbon composite by designing two different structures. Therefore, a core-shell structure of Sb2S3 nanoparticle confined within a porous carbon shell (~100 nm thick) and Sb2S3 nanoparticles reinforced with planar graphene sheets were synthesized, followed by binder-free electrode fabrication by electrophoretic deposition. The electrochemical results demonstrate that core-shell Sb2S3@C shows improved electrochemical performance in lithium-ion batteries with rate capacity reaching ~215 mAh.g−1 at ~4 Ag−1 current rate and long cycle life (~283 mAh.g−1 at ~1Ag−1 over 500 cycles with ~99.6% Coulombic efficiency). On the contrary, Sb2S3/RGO showed favorable results in sodium-ion batteries with an average specific capacity of ~300 mAh.g−1 at ~0.1 Ag−1 current rate up to 100 cycles and good rate capability (~210 mAh.g−1 at ~1 Ag−1 current rate with ~99% Coulombic efficiency). The difference electrochemical performance of Sb2S3@C and Sb2S3/RGO in lithium-ion and sodium-ion batteries attributed to the difference in charge transfer resistance, SEI resistance, and phase evolution as confirmed by electrochemical impedance spectroscopy, ex situ XANES, and XRD study of cycled electrodes. Also, superior Na-ion and Li-ion reaction kinetics in Sb2S3/RGO and Sb2S3@C was verified by diffusion coefficient (DNa and DLi) measurements. These results demonstrate that Sb2S3/carbon composite architecture selection is an important factor for designing conversion-cum-alloy anodes in lithium and sodium batteries.

Sb2S3 nanoparticles anchored on N-doped 3D carbon nanofibers as anode material for sodium ion batteries with improved electrochemical performance

Antimony sulfides, owing to their high theoretical specific capacity, are considered promising anode materials for sodium-ion batteries (SIBs). However, antimony sulfides suffer from inferior rate performance and rapid capacity fading due to the poor conductivity and structural instability of their intrinsic physical characteristics in SIBs. Here, a two-step concise method is reported to synthesize antimony sulfide composite structures with Sb2S3 nanoparticles anchored on N-doped 3D carbon nanofibers (SNCFs). The N-doped 3D carbon nanofibers (NCFs) were prepared by electrospinning, and then the Sb2S3 nanoparticles were grown on NCFs by an in situ ultrasonic-assisted method. Benefitting from the synergistic effects between Sb2S3 nanoparticles and NCFs, the SNCFs show a high capacity and long lifespans in SIBs. The as-prepared SNCFs provide a specific capacity of ~412 mAh g−1 after 50 cycles with a current density of 50 mA g−1, which is ascribed to the enhanced transfer of electrons and ions resulted in the high electrical conductivity, good structural integrity and favorable binding energy between Sb2S3 nanoparticles and NCFs.