Sulfide Materials Research Articles

Review of NiS-Based Electrode Nanomaterials for Supercapacitors

As a new type of energy storage device, supercapacitors have the advantages of high-power densities, high safety factors, and low maintenance costs, so they have attracted widespread attention among researchers. However, a major problem with supercapacitors is that their energy densities are not high enough, which limits their application. Therefore, it is crucial to expand the application scenarios of supercapacitors to increase their energy density as much as possible without diminishing their advantages. The classification and working principles of supercapacitors are introduced in this paper. The electrochemical properties of pure NiS materials, NiS composites with carbon materials, NiS composites with sulfide materials, and NiS composites with transition metal oxides for supercapacitors are summarized. This paper may assist in the design of new electrode materials for NiS-based supercapacitors.

Epitaxial Growth of π-SnS on PbS Substrates

Epitaxial growth of the newly discovered metastable cubic tin sulfide (π-SnS) material was studied theoretically and experimentally. Lead sulfide (PbS) substrates possess a small lattice mismatch with π-SnS and are therefore suitable substrates for epitaxial growth. Very recently, epitaxial growth of π-SnS(111) on PbS(111) and π-SnS(110) on PbS(110) was reported. The interfacial energies of π-SnS(111) on PbS(111), as well as π-SnS(100) on PbS(100), were calculated and found to be smaller than their corresponding pristine surface energies, which give rise to the stable epitaxial growth of π-SnS on PbS. Moreover, we experimentally confirmed the epitaxial growth of π-SnS(100) onto PbS(100) as predicted by the theoretical results. These results establish the pathway of epitaxial growth of π-SnS compact thin films in desired orientations and thus bring their applications closer.

Facile synthesis of neuronal nickel–cobalt-manganese sulfide for asymmetric supercapacitors with excellent energy density

A neuronal nickel–cobalt–manganese sulfide material with a large surface area and high porosity can be homogeneously grown along a nickel foam via a simple one-step hydrothermal procedure. An optimal molar ratio of Ni, Co, Mn, and thiourea of 3:1:1:5 was obtained by adjusting the molar ratio of thiourea. This binder-free composite material supported by a nickel foam can be directly used as a battery-type electrode for supercapacitors. Under the optimal hydrothermal conditions, the battery-type electrode exhibited excellent electrochemical properties with a favorable specific capacitance (2805.3F/g, 1 A/g) and good rate properties (87.7 %, 10 A/g) because of the synergistic effect of the multiple transition metals. Furthermore, the battery-type electrode exhibited a remarkable capacitance retention rate (82.9 %, 10 A/g) after 10,000 cycles of electric charging and discharging owing to the addition of Mn, which suggests excellent cycle stability. Furthermore, an asymmetric supercapacitor (ASC) device prepared using the battery-type electrode material and activated carbon electrode exhibited a considerable energy density (86.9 W h kg−1) at a high power density (799.1 W kg−1). After charging for 26 s to 3.2 V, two ASC devices in series could light two red-light-emitting diodes for at least 300 s. Thus, a simple and effective synthesis scheme can be designed to prepare high-performing supercapacitors.

In-situ-foaming synthesis of cheese-like Fe3S4/Ti3C2Tx electrode material with both high energy and power density for Al/Zn-ion supercapacitors

Although supercapacitor technology has been proposed as a promising new-generation energy means for its rapid charging speed and high operation safety, the shortcoming of low energy density has long been a big obstacle due to the low voltage window and storage capacity. In this study, a new kind of electrode material of Fe3S4/Ti3C2Tx has been proposed by a facile in-situ-foaming strategy through the reaction of Na2S with Fe(NO3)3. Herein, the byproducts of trace H2S and H2 gases were found to appear and expel, creating a lot of pores inside the Fe3S4/Ti3C2Tx composites with a cheese-like heterostructure. Therefore, the maximum specific capacity of Fe3S4/Ti3C2Tx-42% is measured up to 305.8 C g−1 at 2 A g−1, 3.4 times that of Fe3S4 and 5.9 times that of Ti3C2Tx. When Fe3S4/Ti3C2Tx-42% is assembled as a cathode for the Al-ion capacitors and Zn-ion capacitors, the devices both possess superior electrochemical performance. Especially for the Zn-ion capacitors, the device exhibits a high power density of 5500 W kg−1 at a maximum energy density of 61 W h kg−1 and a high stability after 10,000 cycles, showing a distinct advantage over previously reported literatures. Density functional theory (DFT) simulation and XPS analysis are used to validate the beneficial transformation mechanism of reactive sites, thus providing a novel idea for solving the poor structural stability of sulfide materials and MXene-based nanomaterials.

Broadband single-cell-driven multifunctional metalensing

Metasurfaces are artificially engineered ultrathin photonic components that can be freely designed to exhibit unprecedented capabilities of highly-efficient electromagnetic wave manipulation. The ever-growing demand for miniaturized photonic devices for emerging applications, like imaging, spectroscopy, biosensing, and quantum information processing, consistently requires broadband multifunctional and highly-efficient meta-devices. Recent years have witnessed tremendous advancements in metasurfaces; however, investigating the novel platform to realize broadband metasurfaces that integrate multiple functionalities in a single-layered structure would be an obvious technological extension. Here, we present a broadband single-cell-driven multifunctional metasurface platform capable of manipulating electromagnetic waves over a wide range of visible wavelengths (475−650 nm). A lossless zinc sulfide material exhibiting a sufficiently large refractive index and negligible extension coefficient across the visible spectrum is exploited to demonstrate the state-of-the-art meta-devices. Furthermore, a well-known spin-decoupling technique is implemented to multiplex different optical phenomena into a single-cell-driven structure. For proof of the concept, we demonstrate two meta-devices that provide transverse and longitudinal splitting of different optical phenomena for the visible wavelengths. The presented zinc sulfide material and unique design philosophy to achieve broadband multifunctional meta-devices may find potential applications in polarization and dispersion analyzers, sensing, optical communication, and many more.

Non-enzymatic rapid sensing platform based on iron doped lead sulfide nano-interfaces for chloramphenicol

The World Health Organization urges strongly to change our needs for the prescription and use of antibiotics. This indicates the severe problem of antibiotic resistance evolving as a universal risk to the masses. Chloramphenicol (CAP) is one such antibiotic, banned internationally, however, it is still being utilized in developing countries due to its low cost and high efficacy. Therefore, routine monitoring of CAP is necessary for humans, food items, and other sources. In this study, lead sulfide (PbS) and different metals [iron (Fe) and cobalt (Co)] doped PbS nanostructures are used for the electrochemical detection of CAP. The PbS nanoparticles and their variants are prepared by the hydrothermal method. Physical, chemical, and surface characterization are done by XRD, SEM, FTIR, PL spectroscopy, and DLS analysis. Under optimum conditions, a quantitative kinetic study for all materials is done in the concentration range of 0.001 μM to 1.5 μM of CAP solution. Fe-doped lead sulfide materials showed a good linear response, sensitivity, and selectivity with a corresponding limit of detection of 0.13 μM (S/N = 3). For selectivity analysis of Fe-doped PbS, chlorfenicol, thiamphenicol, and clindamycin were used as competitors because of their structural and functional similarity with template (CAP) molecules. The electrochemical nano-sensors based on Fe-doped PbS have the potential to detect CAP even in the presence of interfering agents.

First-principles assessment of chemical lithiation of sulfide solid electrolytes and its impact on their transport, electronic and mechanical properties

Sulfide-based solid electrolytes (SEs) have received considerable attention, but their practical application is hindered by the lack of chemical stability. When in contact with Li metal, sulfide SEs may undergo decomposition induced by lithiation, which could be largely responsible for the high interfacial impedance observed between them. While the underlying mechanism is still uncertain, this first-principles study examines the structural and compositional evolution of sulfide materials, Li3PS4 and Li10GeP2S12, associated with chemical lithiation and its impact on their transport, electronic and mechanical properties. Our calculations demonstrate that the lithiation reaction is thermodynamically favorable until reaching full lithiation in which PS43− and GeS44− tetrahedral anions are completely decomposed to S2−, P3- and Ge4− atomic ions. This process is also found to involve the transition formation of small P(Ge) clusters and more importantly an increase in the relative density which may cause void formation and thus structural failure near the Li metal/SE interface. Moreover, our analyses highlight that, even when fully lithiated, the sulfide materials could retain the high Li-ion conductivity as well as the ability to block electron transport. This suggests that the chemical decomposition of sulfide SEs would not be the only factor that is responsible for the increase of interfacial impedance during electrochemical cycling.

DFT-study supported synergistic electrochemical supercapacitor performance of Bi2MoS6 nanosheets

Synergistic electrochemical performance of the bismuth molybdenum sulphide (Bi2MoS6, BMS) nanosheets can be beneficial for fast ion exchange kinetics in electrolyte solution for energy storage performance. Bismuth sulphide (Bi2S3, BS), molybdenum sulphide (MoS2, MS), and BMS electrode materials of different morphologies are grown on stainless-steel (SS) conducting substrate using a wet chemical process. A 0 - 1 V operating potential window vs. Ag/AgCl has been utilized for half-cell analysis wherein, 947.4 F g−1 specific capacitance is obtained for BMS nanosheet-like electrode at 0.6 Ag−1 current density with nearly 97 % stability which is better than BS and MS electrode materials. Full understanding of synergistic effect i.e., enhancement of electrochemical properties, has clearly been revealed by applying ab-initio theoretical calculations using density functional theory. The values of power density and energy density of the as-constructed symmetric supercapacitor device by using BMS electrode are respectively found to be 1130 Wkg−1 and 85 Whkg−1. A panel of forty-two LEDs coupled in series has been powered through symmetric device to demonstrating the practical application of the as-prepared nanosheet-type BMS electrode material for commercial feasibility.

Stability and synthesis across barium tin sulfide material space

The underexplored Ba–Sn–S phase space is explored at various temperatures and cation ratios with combinatorial sputtering, crystallizing rocksalt-derived phases, Ba2SnS4, and Ba7Sn5S15. These findings are supported by DFT computed phase diagrams.

Ultrafine aluminum sulfide nanocrystals anchored on two-dimensional carbon sheets for high-performance lithium-ion batteries.

Aluminum sulfide is a novel light metal sulfide, which possesses multiple advantages for lithium storage, including high theoretical capacity, proper discharge potential and good conductivity. However, much research has not been done in areas related to light metal sulfide materials. Herein, we synthesized Al2S3/C nanocomposite by a facile one-step ball milling method. This simple method not only effectively achieves the uniform composite of Al2S3 nanoparticles and carbon sheets, but also controls Al2S3 into ultrafine nanocrystals. Al2S3/C electrode demonstrates very outstanding lithium storage performance with large reversible specific capacity (1249 mAh g-1 at 100mAg-1), remarkable rate capability (670 mAh g-1 at 5000mAg-1) and superior long-cycling stability (retaining 850 mAh g-1 even after 1000 cycles at 1000mAg-1). Moreover, the reversible lithium storage behavior and excellent diffusion kinetics of Al2S3/C are unveiled deeply. This work provides an inspiration to develop new light metal sulfide materials for the next-generation high-performance lithium ion battery.

Structural tuning of copper sulfide material for sodium-ion batteries.

In this work, single-crystal and twin-crystal copper sulfide materials are constructed in a regulatable and controlled manner. Twin boundaries are engineered into the copper sulphide material to significantly improve its electrochemical performance. The results demonstrate that structure tuning with twin crystals is an effective strategy for enhancing electrochemical reactions, and also sheds light on the design of electrode materials for sodium ion storage.

Advances in the one-step synthesis of 2D and 3D sulfide materials grown by pulsed laser deposition assisted by a sulfur thermal cracker

Advances in the one-step synthesis of 2D and 3D sulfide materials grown by pulsed laser deposition assisted by a sulfur thermal cracker

Electrospun Fe1-xS@nitrogen-doped carbon fibers as anode material for sodium-ion batteries

Iron sulfide is a potential anode material for sodium-ion batteries because of its abundant natural resources and high theoretical specific capacity. However, they show poor cycling performance due to the serious volume change of iron sulfide materials during the process of charge and discharge. In this work, Fe1-xS particles are encapsulated in nitrogen-doped 1D carbon fiber material by an electrospinning/high-temperature vulcanization process. The carbon fiber skeleton effectively stabilized the structure of the material; The heteroelement doped carbon improved the electrical conductivity properties and capacitive sodium storage performance. Owing to the unique structure of nitrogen-doped 1D carbon fiber, the material obtains good cycling stability and rate capability. The optimized Fe1-xS@ nitrogen-doped carbon fibers (Fe1-xS@NCFs) material was used as the anode of the sodium-ion batteries and maintained a discharge capacity of 382 mAh g-1 after 100 cycles at 0.1 A g-1 and 330 mAh g-1 after 150 cycles at 1 A g-1.

Lithium‐Rich Li2TiS3 Cathode Enables High‐Energy Sulfide All‐Solid‐State Lithium Batteries

AbstractOutstanding interfacial issues exist between oxide cathodes and sulfide electrolytes in all‐solid‐state lithium batteries (ASSLBs), while high‐capacity Li‐rich sulfide cathodes are gaining attention for application. Herein, a sulfide cathode active material Li2TiS3 (LTS) that is chemically compatible with sulfide solid electrolytes, is used in high‐performance Li6PS5Cl‐based ASSLBs at room temperature. The batteries demonstrate a maximum discharge capacity of 423.2 mAh g−1 (910 Wh kg−1 based on Li2TiS3) with 95% capacity retention after 100 cycles at 0.1 C (0.33 mA cm−2). Traces of elemental sulfur on the surface of LTS are mainly responsible for the excessive Li‐intercalation and the capacity exceedance. The Li6PS5Cl is also found to offer a nonnegligible capacity (at least 27% of excess capacity) by comparing the Li6PS5Cl‐based and Li3YCl6‐based cells using Li2TiS3 as cathode active material. During long cycling, the amorphization and degradation of Li2TiS3 and Li6PS5Cl cause capacity decay. The electrochemical kinetics of Li6PS5Cl‐based cells are evaluated as a reference to further exploit the potential of Li2TiS3 material for practical applications in ASSLBs. Overall, this superior Li‐rich sulfide material is an attractive alternative to oxide cathodes for the development of high‐performance ASSLBs.

Enhanced cycling performance of surface-amorphized Co3S4 as robust cathode for supercapacitors

The interfacial engineering via surface amorphization is an effective strategy to regulate the structure and character of material. Herein, a facile hydrothermal method followed by NaBH4 treatment is proposed to fabricate surface-amorphized Co3S4 (SA-Co3S4). XRD and SEM characterization implies the micro flower structure of Co3S4. TEM test further demonstrates the heterointerface between crystal Co3S4 core and defect-rich amorphous Co3S4 surface, which can reduce electron/ion transport path and accelerate internal charge transfer rate, thus enhancing the integral electrical conductivity. Electrochemical measurements imply that the SA-Co3S4 displays satisfying specific capacitance of 1043.9 F g−1 at 0.5 A g−1 and good rate performance. By employing SA-Co3S4 as a cathode, and active carbon as an anode, the asymmetric supercapacitor exhibits a high energy density of 41.9 Wh kg−1 at a power density of 162 W kg−1 and good cycling durability (above 90 % retention rate after 10,000 cycles). This work offers a novel structure design strategy for fabricating cobalt sulfide materials with high conductivity and electrochemical performances.

Soil-archaeological studies of Koy-Gunzhar Scythian tumuli (Kazakhstan): building materials and techniques, diagenetic transformations of buried paleosols

The tumuli of the Koy-Gunzhar burial ground (2400-2000 cal years BP) in the North Kazakhstan are monumental earthen mounds, built in honour of the Scythian elite. The tumuli, besides representing the diversity of the building techniques for such earth burial mounds, also provide a unique opportunity to study the direction and character of the paleosol diagenesis for nearly 2400 years. This soil-archaeological study aimed to reveal mound building techniques, the characteristics of materials used for construction, and diagenetic changes of the buried paleosols. The comparative analysis of tumulus embankments and buried soils (their genesis and diagenetic transformations) provided the opportunity to establish the source of the building material and to reconstruct some details of the building technologies. For instance, the Calcic Someric Kastanozem (Arenic, Protosodic), buried by loam-sandy and sandy substrate of the tumulus 3, corresponds to dry steppe conditions and has no considerable signs of diagenetic transformations, whereas the paleosol under the tumulus 1 was affected by strong diagenetic transformation supposedly due to acid drainage from the embankment which originally contained sulfidic material being subjected to oxidation and acidification after the tumulus construction. Diagenesis was manifested in the redistribution of pedogenic carbonates and enrichment in iron, magnesium, manganese, and aluminum compounds in the upper 32 cm of the buried soil. These elements were partially accumulated at the carbonate geochemical barrier (over Bk horizon of the buried soil). This soil was transformed by diagenesis from Kasrtanozem to Mollic Cambic Umbrisol (Epiloamic, Katoarenic). The builders of the tumulus 1 used a loamier substrate to construct the mound, different from the parent material for adjacent soils (loamy sands and sands). The loamier substrate ensured the firmness of the mound construction. The builders employed an uncommon technique to produce a mound with defined properties and used foreign building materials brought from the distance.

Layered metal sulfide NMTS for rapid removal of radioactive strontium ions from aqueous solution

A one-step hydrothermal method was used to synthesize a quaternary metal sulfide material, NMTS, to remove strontium ions from simulated radioactive wastewater, in which metal tin was replaced by tin and magnesium salts to reduce the cost of the raw materials. The adsorption characteristics and behavior of Sr2+ were studied using batch experiments. NMTS has a layered structure, and the approximate molar ratio of Na:Mg:Sn:S is 4:1:10:23, with an approximate 61% reduction in the raw material cost compared to NaTS. NMTS exhibited ultrafast kinetics for Sr2+ with rapid adsorption of 97.1% in 0.5 min and 99.8% at an equilibrium time of 3 min, followed by the pseudo-second-order model and Langmuir model with a maximum adsorption amount of 52.6 mg/g at 298 K. NMTS had a high affinity for Sr2+ with Kd values of >106 at pH values ranging from 4 to 11. The adsorption of Sr2+ mainly involves ion exchange and surface adsorption. Ion exchange Na+ for Sr2+ was predominant with initial Sr2+ concentrations ranging from 5 to 20 mg/L, and both ion exchange and surface SrS bonding interactions occurred with initial Sr2+ concentrations higher than 20 mg/L. Sodium and potassium ions had little effect on the adsorption of Sr2+, whereas the presence of calcium and magnesium ions greatly affected it. In addition, NMTS also exhibited high selectivity for the adsorption of cobalt, nickel, and manganese, followed by Ni2+ > Sr2+ > Mn2+ > Co2+. NMTS is a promising adsorbent for removing Sr ions from aqueous solutions.

Improved Catalytic Activity and Stability of Co9S8 by Se Incorporation for Efficient Oxygen Evolution Reaction.

Combining an excellent electrocatalytic activity with the good structural stability of Co9S8 remains challenging for the oxygen evolution reaction (OER). In this study, density functional theory was used to demonstrate the importance of moderate adsorption strength with *O and *OOH intermediate species on Co9S8 for achieving excellent electrocatalytic performances. A novel strategy was proposed to effectively optimize the *O oxidation to *OOH by introducing Se heteroatoms to adjust adsorption of the two intermediates. This process also allowed prediction of the simultaneous enhancement of the structural stability of Co9S8 due to the weak electronegativity of a Se dopant. The experimental results demonstrated that Se doping can regulate the charge density of Co2+ and Co3+ in Co9S8-xSex, leading to a substantially improved OER performance of Co9S8-xSex. As a result, our Co9S6.91Se1.09 electrode exhibited an overpotential of 271 mV at 10 mA cm-2 in a 1.0 M KOH solution. In particular, it also demonstrated an excellent stability (∼120 h) under a current density of 10 mA cm-2, indicating the potential for practical applications. Overall, the proposed strategy looks promising for regulating the electronic structures and improving the electrochemical performances of sulfide materials.

Facile fabrication of Zn3In2S6@SnS2 3D heterostructure for efficient visible-light photocatalytic hydrogen evolution

A series of Zn3In2S6@SnS2 photocatalysts with different SnS2 mass ratios were prepared by hydrothermal method. Two photoactive sulfide materials were prepared into composite materials for photocatalytic hydrogen evolution under visible light excitation. The unique structure accelerates the separation and transfer of photogenerated electrons and holes. Due to its unique composition advantages, the Zn3In2S6@SnS2 three-dimensional heterostructure without any co-catalyst (SnS2 doping amount of 10 %) exhibited remarkable activity, and its hydrogen production rate was 15443 μmol h−1g−1, indicating high photocatalytic stability for water decomposition. Based on photoelectrochemical (PEC) and hydrogen evolution test, a reasonable photocatalytic mechanism was proposed.

Tweaking the performance of thin film CIGS solar cell using InP as buffer layer

In this paper, a high performing copper indium gallium selenide (CIGS) (CuIn1−xGaxSe2) based solar cell is designed using less toxic indium phosphide (InP) as a buffer layer. Conventional CIGS solar cell uses toxic cadmium sulfide (CdS) material as a buffer layer. Here InP is used in place of CdS, which is not only environmentally friendly but also gives better performance in terms of power conversion efficiency (PCE). In this work, proposed device structure comprises of following layers: glass substrate/n-ZnO (window layer)/n-InP (ETL)/p-CIGS (absorber)/p-MoS2 (HTL)/metal back contact. Device optimization is done by varying thickness, defect density, and doping concentration of absorber and buffer layers. Various electrical parameters like open circuit voltage (Voc), short circuit current density (Jsc), fill factor (F.F.), quantum efficiency (Q.E.), and PCE are obtained to study the behavior of the device. The performance of the proposed solar cell is also investigated by varying series-shunt resistance, temperature, and work function of front and back contact electrodes. The proposed structure shows maximum efficiency of 28.01% (Voc=0.8294 V, Jsc=39.26 mA/cm−2, FF=86.01%) at room temperature (300 K). All the analyses are done with the help of the SCAPS-1D simulation program.