Bismuth sulfide (Bi
2
S
3
) as a potential Na‐storage material relies upon its special layered structure and high volumetric capacity. However, the electrochemical activity of pure Bi
2
S
3
is greatly limited during the sodiation/desodiation process. The integration of Bi
2
S
3
with reduced graphene and a particular carbon is explored to acquire active composite anodes for sodium ion batteries (SIBs). This special carbon is based on trimesic acid (H
3
BTC) as a carbon source, which effectively prevents the aggregation of Bi
2
S
3
particles in the synthesis process. Compared with other carbon sources, this type of carbon source is more likely to diffuse into the interior of the precursor hole. Hence, the Bi
2
S
3
/C indicates higher reversible capacities (368 and 314?mAh?g
?1
after 100 cycles and 200 cycles at 100?mA?g
?1
) than bare Bi
2
S
3
or Bi
2
S
3
@RGO. Thus, Bi
2
S
3
/C is considered as a prospective electrode material for rechargeable batteries.
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Highly oriented polycrystalline Bi2S3 thin films with crystallinities superior to those obtained in chemically deposited Bi2S3 thin films were prepared by direct evaporation of bismuth sulfide precipitate. The XRD patterns of thes...
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Highly oriented polycrystalline Bi2S3 thin films with crystallinities superior to those obtained in chemically deposited Bi2S3 thin films were prepared by direct evaporation of bismuth sulfide precipitate. The XRD patterns of these films show preferential growth of bismuth and bismuthinite planes, and this growth could be correlated to substrate temperature and substrate type. For films deposited on glass substrates at room temperature, the XRD pattern shows an incipient growth of Bi2S3 (bismuthinite) along the [020], [220], and [021] directions. At these angles, Bi planes also diffract and might be the major component of this alloy, XRD spectra of films deposited on bare glass in the substrate temperature range 150-300 degrees C show that the film growth evolves from an oriented to a more random pattern. At a substrate temperature of 250 degrees C, the crystallization of bismuth and bismuthinite is accelerated on glass substrates with a Cr coating and inhibited on glass substrates with a SnO2 coating. The reflectance spectra of the films deposited at 250 degrees C on uncoated and SnO2-coated glass substrates show that the crystallinity is dominated by Bi2S3, whereas in films deposited on a Cr grid Bi is a strong component. The optoelectronic properties of the deposited films indicate very conductive layered structures with E-g values in the range 1.2-1.6 eV. Compared with the above, chemically deposited thin films were less crystalline and more stoichiometric, with a lower conductivity and higher optical band gap (1.5-2.0 eV). The possible application of these films in heterojunction and photoelectrochemical devices is suggested. (C) 1998 Academic Press. [References: 23]
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In general, Bi2Te3 and related alloys show the best thermoelectric performance at near-room temperature region below about 423 K, which is in some cases not high enough for waste heat recovery. In order to raise the operation temp...
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In general, Bi2Te3 and related alloys show the best thermoelectric performance at near-room temperature region below about 423 K, which is in some cases not high enough for waste heat recovery. In order to raise the operation temperature on the basis of Bi2Te3 technology, S element was introduced into Bi2Te3 to synthesize a ternary tetradymite compound, Bi2Te2S, and the thermoelectric properties were analyzed. In this study, Bi2S3 was considered, instead of using elemental S, to avoid the issues arising from the volatility of S. Compared with Bi2Te3, undoped Bi2Te2S shows higher Seebeck coefficients (S-max = -210.9 mu V K-1 at 523 K) but also higher resistivity (rho(min) = 26.5 mu Omega m at 323 K), resulting in decreased power factor (PFmax = 1.49 mW K(-2)m(-1) at 373 K). However, low thermal conductivity (K-min = 0.987 WK-1 m(-1) at 473 K) produced higher ZT at T >= 423 K than Bi2Te3, reaching about 0.66 at 473 K. At the same time, the bipolar conduction was reduced due to the enlarged band gap of about 0.22 eV, which was estimated from the S-T curve. After additional hot deformation at 793 K, undoped Bi2Te2S shows remarkably improved values of power factor (PFmax = 2.62 mW K(-2)m(-1) at 323 K) and ZT (ZT(max) = 0.86 at 473 K), which was ascribed to increased carrier concentration. In addition, the highly anisotropic transport properties of Bi2Te2S were suggested to be another origin, which was revealed by the first-principles calculations. In summary, Bi2Te2S is a promising candidate for thermoelectric generation at the intermediate temperature region 473-573 K where Bi2Te3 shows degraded performances. (C) 2019 Elsevier B.V. All rights reserved.
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Bi2S3 and Fe3O4 nanostructures as well as Bi2S3@Fe3O4 nanocomposites were produced using hydrothermal synthesis. Scanning electron microscopy (SEM), energy dispersive spectra (EDS) and X-ray diffraction (XRD) were used in the char...
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Bi2S3 and Fe3O4 nanostructures as well as Bi2S3@Fe3O4 nanocomposites were produced using hydrothermal synthesis. Scanning electron microscopy (SEM), energy dispersive spectra (EDS) and X-ray diffraction (XRD) were used in the characterization of the nanocomposites. The effect of heat treatment on chemical, physical and magnetic properties of the nanostructures was investigated in this study. It was determined that the duration of heat treatment affects the size and shape of the nanostructures. Bi2S3 samples produced using less than 12 h of heat treatment formed in nanoflower-like shapes whereas when the heat treatment was extended to 24 h, the samples formed in nanoribbon-like shapes. The study concludes that an increase in the duration of heat treatment enhances the saturation value of magnetization of Fe3O4 nanostructures. Bi2S3 nanostructures were doped with Fe3O4 nanostructures to produce Bi2S3@Fe3O4 nanocomposites which have significant magnetic properties. An increased duration of heat treatment increases the magnetic saturation values of Fe3O4 and Bi2S3@Fe3O4 nanostructures. Bi2S3, Fe3O4 and Bi2S3@Fe3O4 samples show X-ray imaging contrast enhancement properties.
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Herein, we investigated the influence of sulfur (S) addition on the phase formation behavior and thermoelectric transport properties of n-type Cu0.008Bi2Te3. A complete single phase of rhombohedral Bi2Te3 was formed in Cu0.008Bi2T...
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Herein, we investigated the influence of sulfur (S) addition on the phase formation behavior and thermoelectric transport properties of n-type Cu0.008Bi2Te3. A complete single phase of rhombohedral Bi2Te3 was formed in Cu0.008Bi2Te2.8S0.2, whereas a mixture of Bi2Te3 and Bi2Te2S1 phases was generated at higher S contents. We elucidated the complex effects of S substitution at Te-site on transport properties of Cu0.008Bi2Te3; (1) increase in density-of-states effective mass, (2) decrease in weighted mobility ratio, (3) reduction in lattice thermal conductivity, and (4) reduction in bipolar thermal conductivity. Despite the slight deterioration in electronic transport properties, a maximum thermoelectric figure of merit (zT) of 0.82 was achieved at 400 K in Cu0.008Bi2Te2.8S0.2 due to the synergetic effect of intensified point defect phonon scattering in a wide temperature range and suppressed bipolar thermal conduction at elevated temperatures.
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The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal microbalance, X-ray diffraction, and energy dispersive Xray analysis ...
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The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal microbalance, X-ray diffraction, and energy dispersive Xray analysis methods. During the bismuth sulfide coating reduction in Watts background electrolyte in the potential region from 0.4 to 0.6 V, the Bi2S3 and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S2 ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed increase in coating mass in the potential region 0.1 to 0.4 V is conditioned by Ni2+ ions reduction before the bulk deposition of Ni, initiated by Bi2S3. In this potential region, the reduction of Bi(III) oxygen compounds can occur.After the treatment of as-deposited bismuth sulfide coating in nickel plating electrolyte at E=0.3 V, the sheet resistance of the layer decreases from 1013 to 500–700 Ω cm. A metalrich mixed sulfide Ni3Bi2S2–parkerite is obtained when asdeposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential close to the equilibrium potential of the Ni/Ni2+ system and then annealed at temperatures higher than 120 °C.
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A BiVO4/Bi2S3 composite comprising Bi2S3 nanowires on top of a BiVO4 film was prepared via hydrothermal reaction. Because additional Bi3+ ions were not delivered during the reaction, BiVO4 served as the Bi3+ ion source for the dev...
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A BiVO4/Bi2S3 composite comprising Bi2S3 nanowires on top of a BiVO4 film was prepared via hydrothermal reaction. Because additional Bi3+ ions were not delivered during the reaction, BiVO4 served as the Bi3+ ion source for the development of Bi2S3. A detailed growth mechanism of the nanowire was elucidated by an analysis of the concentration gradient of Bi3+ and S2- ions during the reaction. The in situ growth was followed by the etching of BiVO4 to Bi3+ and VO43- ions and regrowth to Bi2S3, which resulted in the rapid evolution of nanowires on the BiVO4 substrate. The fabricated BiVO4/Bi2S3NW composite exhibited an improved photoelectrochemical activity compared to other Bi2S3 samples. The improved efficiency was mainly attributed to both improved charge separation and effective adhesion obtained by the in situ growth.
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Bismuth sulfide (Bi2S3) has been considered a potential electrode material for Li storage due to its high theoretical capacity and intriguing reaction mechanism. In this work we have designed a Bi2S3@CNT nanocomposite as a sodium ...
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Bismuth sulfide (Bi2S3) has been considered a potential electrode material for Li storage due to its high theoretical capacity and intriguing reaction mechanism. In this work we have designed a Bi2S3@CNT nanocomposite as a sodium ion (Na-ion) battery anode material, and studied its electrochemical performance. The layer structured Bi2S3 provides host sites for insertion of Na-ion and the carbon nanotube (CNT) in the Bi2S3@CNT nanocomposite serves as a highly conducting network to promote electron transport. The results show that the Bi2S3@CNT nanocomposite exhibits a high and stable capacity in the 0.01-3 V (vs. Na/Nal voltage region, notably outperforming the bare Bi2S3 material. The Bi2S3@CNT nanocomposite as Na-ion anode material is able to discharge 84.4 mAh g(-1) capacity at 60 mA g(-1) over 60 full cycles. (C) 2015 Elsevier B.V. All rights reserved.
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We developed a facile in-situ growth method to construct amorphous-based Bi2S3/Bi2WO6 heterostructures at room temperature. As demonstrated by HRTEM, XPS and EDX-mapping, amorphous state Bi2S3 dispersed uniformly on the surface of...
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We developed a facile in-situ growth method to construct amorphous-based Bi2S3/Bi2WO6 heterostructures at room temperature. As demonstrated by HRTEM, XPS and EDX-mapping, amorphous state Bi2S3 dispersed uniformly on the surface of crystalline Bi2WO6 hollow spheres. The photocatalytic activities of prepared Bi2S3/Bi2WO6 heterostructures were evaluated by the photodegradation of RhB and TC under visible light irradiation, indicating that the introduction of appropriate amorphous Bi2S3 significantly improved the photocatalytic activity of Bi2WO6. The amorphous/crystalline contact in Bi2S3/Bi2WO6 heterostructures played a crucial role in the enhancement of photocatalytic efficiency. Based on DRS, photoluminescence spectra, photocurrent intensity, electrochemical impedance spectroscopy and OCVD measurements, it was proposed that the enhanced performance could be ascribed to increased visible light utilization, promoted separation efficiency and prolonged life time of photogenerated electron-hole pairs by the introduction of amorphous Bi2S3. This work may provide new insights into the construction of amorphous-based composited heterostructures for improving photocatalytic activity.
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Here, we report a Bi2S3 nanorod obtained from the topotactic transformation of single-crystalline Bi202S and demonstrate its successful performance of enhanced photocatalytic CO2 reduction. The prepared Bi2S3 nanorods exhibit the ...
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Here, we report a Bi2S3 nanorod obtained from the topotactic transformation of single-crystalline Bi202S and demonstrate its successful performance of enhanced photocatalytic CO2 reduction. The prepared Bi2S3 nanorods exhibit the enlarged band gap with a more negative conduction band position while its single-crystalline characteristic remains unchanged. The accelerated transformation and separation of photogenerated carrier and enhanced adsorption and activation of CO2 on Bi2S3 nanorods is clearly different from that of bulk-Bi2S3. As a result, the production of photocatalytic CO2 reduction to CH4 on Bi2S3 nanorods is 59.9 umol g_1h_1 under visible light irradiation and a simulated air atmosphere, which is 2.2 times higher than that of bulk-Bi2S3 and remains persistent activity during the repetition experiments. This discovery is believed to pave further exploration for designing unconventional nanostructures and promoting their widely distributed environmental application.
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