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Urea-assisted water electrolysis is a promising strategy for the high-efficiency hydrogen production due to the more favorable anodic thermodynamic potential of urea oxidation reaction (UOR) than that of oxygen evolution reaction (OER). However, the kinetics of UOR is sluggish and thereby the fabrication of UOR catalyst which also possesses cathodic hydrogen evolution reaction (HER) catalytic performance is ascribed to be the paramount bottleneck due to the hard simultaneous satisfaction between UOR and HER performance metrics. Herein, a hierarchical amorphous-crystalline heterogeneous NiCoS x nanosheet with rich lattice defects grown on nickel foam (NiCoS x /NF) catalyst was proposed via scalable solvothermal method for overall urea-assisted water electrolysis. The NiCoS x /NF only needs an ultralow potential of 1.36 V to drive 100 mA cm−2 for UOR, exceeding that of OER for 220 mV, and an overpotential of 183 mV to obtain 100 mA cm−2 for HER. More importantly, the urea electrolyzer assembled with NiCoS x /NF as both cathode and anode could achieve 10, 100, and 500 mA cm−2 at battery voltages of 1.41 V, 1.55 V, and 1.75 V, respectively, with continuous working for 60 h. Experimental and density functional theory calculations reveal that the strong electronic interactions caused by heterojunctions and lattice defects exposed on the well-accessible NF surface result in the increased proportions of Ni3+ active sites and enhanced conductivity, which should be responsible for the superior UOR and HER performance. • NiCoS x nanosheets with Co 3 S 4 /Ni 3 S 2 /NiCo heterojunctions and rich defects grew on nickel foam. • NiCoS x /NF-based urea-assisted water splitting device show prominent catalytic activity and stability. • Heterojunctions and defects should be responsible for the superior performance of NiCoS x /NF. [ABSTRACT FROM AUTHOR]

Supercapacitors have emerged as a highly promising technology for energy storage, offering benefits such as high power output, adjustable energy density, and robust cyclic stability. The performance of these devices is largely influenced by the electrode materials used, which must provide substantial charge storage, excellent rate capability, and strong conductivity. Among various strategies developed to address these challenges, sulfurization has gained notable attention for its effectiveness in enhancing the electrochemical properties of electrode materials. This review article provides an in-depth examination of the sulfurization process applied to electrodes, aiming to deliver a thorough overview of recent advancements, the effects of sulfur integration on electrode characteristics, and the consequent improvements in supercapacitor performance. It delves into how sulfurization affects the morphology, structure, and composition of electrode materials, including changes in surface area, pore size distribution, crystal structure, and the creation of active sites. The review consolidates findings on enhanced specific capacitance, improved rate capability, extended cycle life, and increased energy density achieved through sulfurization. Additionally, it addresses the challenges and limitations of sulfurization, offering insights into potential solutions and future research directions. [Display omitted] • The cutting-edge approach, sulfurization of electrode materials is discussed. • A comprehensive analysis of the sulfurization process applied to the electrode is presented. • Explores the impact of sulfur incorporation on electrode properties. • Discovers challenges strategies to mitigate future developments. [ABSTRACT FROM AUTHOR]

Rechargeable Mg batteries are a promising energy storage technology to overcome the limitations inherent to Li ion batteries. A critical challenge in advancing Mg batteries is the lack of suitable cathode materials. In this work, we report a cathode design that incorporates S functionality into two‐dimensional metal‐organic‐frameworks (2D‐MOFs). This new cathode material enables good Mg2+ storage capacity and outstanding cyclability. It was found that upon the initial Mg2+ insertion and disinsertion, there is an apparent structural transformation that crumbles the layered 2D framework, leading to amorphization. The resulting material serves as the active material to host Mg2+ through reduction and/or oxidation of S and, to a limited extent, O. The reversible nature of S and O redox chemistry was confirmed by spectroscopic characterizations and validated by density functional calculations. Importantly, during the Mg2+ insertion and disinsertion process, the 2D nature of the framework was maintained, which plays a key role in enabling the high reversibility of the MOF cathode. [ABSTRACT FROM AUTHOR]

The addition of flexible Cu2ZnSnS4 (CZTS) thin film solar cells to titanium (Ti) substrates is an attractive way to achieve the low-cost manufacturing of photovoltaics. Prior research has indicated that the appropriate diffusion of Ti elements can enhance the crystalline growth of CZTS films. However, the excessive diffusion of Ti has been shown to adversely affect the photovoltaic performance of CZTS photovoltaic devices. Therefore, it is essential to regulate the diffusion of Ti elements within CZTS thin films to optimize their photovoltaic properties. The tendency for Ti substrate elements to diffuse into CZTS films is also influenced by the activation energy associated with these Ti elements. The sulfurization temperature is posited to be a critical factor in modulating the diffusion and activation energy of Ti elements within CZTS thin films. Consequently, this research investigates the alteration of the sulfurization temperature of CZTS thin films in order to enhance the properties of these thin films and to examine the diffusion behavior of titanium elements. The results reveal that as the sulfurization temperature increases, the diffusion of Ti elements within the CZTS thin films initially increases, then decreases, and subsequently increases again. This pattern suggests that the diffusion of Ti elements is affected not only by the activation energy of the Ti elements but also by the defect hopping distance within the CZTS thin films. Notably, at a sulfurization temperature of 550 °C, the grains at the base of the CZTS thin film demonstrate an increased density, which is associated with a reduced defect hopping distance, thereby hindering the diffusion of Ti elements within the CZTS thin films. Furthermore, at this specific sulfurization temperature, the slope of the current–voltage (I–V) curve for the CZTS/Ti structure reaches its maximum, indicating optimal ohmic contact characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize few-layer MoS2 on SiO2/Si using sulfurization chemical vapor deposition toward beyond-5G and 6G communication. Fabric-like MoO3(s) was directly placed onto a SiO2/Si substrate to lower the oxygen potential, which is achieved through a shadowing effect on vaporization. Successful results were achieved, yielding MoS2 thin films with a coverage of more than 74% and a crystal size in the range of 50 to 600 μm. Two distinct pathways for MoS2(s) formation from MoO3(s) via MoO2(s) and MoS3(s) were also uncovered. The shadowing effect of MoO3(s) vaporization facilitated the two-dimensional growth of MoS2 by mitigating oxygen partial pressure. Therefore, sulfurization chemical vapor deposition shows great application potential in synthesizing high-quality MoS2 thin films with substantial crystal size and coverage, making them suitable for next-generation communication devices. [ABSTRACT FROM AUTHOR]

Anoxygenic phototrophic bacteria (green and purple sulfur bacteria) thrive in anoxic environments where light penetrates a sulfide-containing (euxinic) water column. Genomic data and photosynthetic bacterial carotenoid pigments should provide complementary information on the spatio-temporal dynamics of anoxygenic phototrophs in modern euxinic environments. In turn, these contemporary depositional settings often serve as analogues for ancient counterparts. However, in some modern environments, DNA-informed patterns of phototrophic sulfur bacteria occurrence do not match distributions of their carotenoid inventories. One possible explanation for these seemingly incompatible observations is that the rapid sulfurization of carotenoids and incorporation into macromolecules via multiple carbon–sulfur bonds prevents or confounds their detection by conventional means. Here, to evaluate this conundrum, we revisit some representative contemporary euxinic environments where anoxygenic phototrophic bacteria have mostly been detected based on genomic analyses. Although free intact carotenoids are sporadically detected in surface sediments, their distributions do not reveal a complete picture. Exogenously sourced fossil carotenoids (e.g., paleorenieratane) is an additional complication. Carotenoid inventories obtained by desulfurization with Raney nickel, on the other hand, stand in stark contrast to those present as free lipids. In particular, sulfur-linked carotenoids present in euxinic lake sediments provide a more complete picture of compositions of anoxygenic sulfur bacterial communities and account for discrepancies reported in previous studies. We observe a closer alignment between genomic data and patterns of sulfurized carotenoids and, importantly, our results highlight how sulfurization serves as a pathway for the rapid modification of highly functionalised lipids and their sequestration into the macromolecular component of sediment extracts. [ABSTRACT FROM AUTHOR]

Sulfur is a promising anion dopant for exploring exotic physical phenomena in complex perovskite oxides. However, sulfurization to the epitaxial single-crystal oxide thin films with high crystallinity is experimentally challenging due to the volatility of sulfur element; thus, sulfurization effects on the associated properties have been scarcely studied. Here, we demonstrate an enhancement of ferroelectric polarization of epitaxial BaTiO3 thin films by sulfur doping. Initially, the epitaxial BaTiO3 thin films with high crystallinity were grown by pulsed laser deposition (PLD). Then, sulfurization to epitaxial BaTiO3 films was performed using a precursor of thiourea (CH4N2S) solution via a spin-coating technique. The crystalline structure of sulfurized BaTiO3 films was identified by X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM). The structural distortion with the elongated out-of-plane lattice constant was observed in the sulfurized BaTiO3 films. Atomic force microscopy (AFM) analyses also confirmed the surface morphology of films after sulfurization. Interestingly, we found an enhanced ferroelectric polarization in sulfur-doped BaTiO3 films accompanying the improved tetragonality in the crystal structure after sulfurization. The increments in the remnant (~34.8%) and saturated (~30.6%) polarizations of sulfurized BaTiO3 films were obtained in comparison with pure BaTiO3 films. Our work could be a primary study for a thorough understanding of the sulfur doping effect in perovskite oxides, opening up the potential of oxysulfide materials.

Transition metal sulfides with designed nanostructures are expected to provide superior electrochemical performance when used as electrode materials for pseudocapacitors compared to their oxide counterparts. In this paper, hollow Co3S4 dodecahedra were successfully prepared using cobalt‐based zeolite imidazolium skeleton (ZIF‐67) as the precursor and thioacetamide (TAA) as the sulfur source combined with a facile one‐step vulcanization process. The hollow cavity structure not only shortens the carrier transport distance but also provides a higher specific surface area and abundant active sites, which promotes an efficient mass transfer process. In addition, the one‐step synthesis of hollow Co3S4 has greater advantages than the one‐step synthesis in terms of cost control and process simplification. The specific capacitance of the produced hollow Co3S4 nanopolyhedra was 668 F/g at 1 A/g and remained at 353 F/g at 10 A/g when used as a pseudocapacitor electrode, demonstrating its superior multiplication capability. In addition, the capacitance retention is 86.4% after 5000 cycles at 4 A/g, indicating its long cycle stability. Notably, employing commercial activated carbon as negative electrode and the as‐prepared hollow Co3S4 polyhedrons as positive electrode, the assembled asymmetry supercapacitor device delivers a high energy density of 20.7 Wh/kg at a power density of 716 kW/kg. The capacitance value of the device remains up to 81.4% after 2000 charging/discharging cycles. The simple synthesis process opens new opportunities to develop advanced hollow nanostructures exhibiting potential for various applications. [ABSTRACT FROM AUTHOR]

Chalcopyrite ores are processed mostly by pyrometallurgical techniques due to the refractory nature of the mineral to the current hydrometallurgical techniques. In order to overcome such refractoriness, pretreatment steps such as sulfurization may be applied to produce different copper phases and therefore improve the metal dissolution in the leaching step. The current study investigated the reaction products of the reaction between chalcopyrite and elemental sulfur at different chalcopyrite/sulfur ratios (1/1 and 1/2), reaction time (60 min and 90 min), and temperature (350ºC, 400°C and 450ºC). The sulfurization experiments revealed that covellite, nukundamite, bornite, and pyrite-like compounds were produced according to the experimental conditions applied. Then, the sulfurization products were submitted to chemical leaching tests at temperatures ranging from 32ºC to 70ºC, whereas bioleaching tests were also carried out with Acidithiobacillus ferrooxidans, at 32ºC. In the chemical leaching experiments at 70ºC, only 14% copper was recovered from the original chalcopyrite sample while the maximum copper extraction was 78% from bornite produced at 450ºC (90 min and mass ratio of chalcopyrite/sulfur of 1/2). On the other hand, copper extraction achieved 96% from the same sulfurization product containing synthetic bornite within 20 days of bioleaching. Bioleaching of the original chalcopyrite sample implied in a copper recovery of only 25% in the same period. Summarizing, the current work showed that chalcopyrite sulfurization at 450ºC was able to transform chalcopyrite into a bornite-like phase, which was chemically leached and bioleached by At. ferrooxidans. [ABSTRACT FROM AUTHOR]

High-temperature carbonized metal-organic frameworks (MOFs) derivatives have demonstrated their superiority for promising electromagnetic wave (EMW) absorbers, but they still suffer from limited EMW absorption capacity and narrow bandwidth. Considering the advantage of microstructure and chemical composition regulation for the design of EMW absorber, hierarchical heterostructured MoS2/CoS2-Co3O4@cabonized cotton fabric (CF) (MCC@CCF) is prepared by growing ZIF-67 MOFs onto CF surface, chemical etching, and carbonization. Aside from the dual loss mechanism of magnetic-dielectric multicomponent carbonized MOFs, chemical etching and carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching and stronger absorption capacity via internal reflection, doped heteroatoms (Mo, N, S) to supply additional dipolar polarization loss, and numerous heterointerfaces among MoS2, CoS2, Co3O4, and CCF that produce promoted conduction loss and interfacial polarization loss. Thus, a minimal reflection loss of −52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sample thickness and filler loading, showing excellent EMW absorption performances. This research is of great value for guiding the research on MOFs derivatives based EMW absorbing materials. [ABSTRACT FROM AUTHOR]

Sulfur is a promising anion dopant for exploring exotic physical phenomena in complex perovskite oxides. However, sulfurization to the epitaxial single-crystal oxide thin films with high crystallinity is experimentally challenging due to the volatility of sulfur element; thus, sulfurization effects on the associated properties have been scarcely studied. Here, we demonstrate an enhancement of ferroelectric polarization of epitaxial BaTiO3 thin films by sulfur doping. Initially, the epitaxial BaTiO3 thin films with high crystallinity were grown by pulsed laser deposition (PLD). Then, sulfurization to epitaxial BaTiO3 films was performed using a precursor of thiourea (CH4N2S) solution via a spin-coating technique. The crystalline structure of sulfurized BaTiO3 films was identified by X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM). The structural distortion with the elongated out-of-plane lattice constant was observed in the sulfurized BaTiO3 films. Atomic force microscopy (AFM) analyses also confirmed the surface morphology of films after sulfurization. Interestingly, we found an enhanced ferroelectric polarization in sulfur-doped BaTiO3 films accompanying the improved tetragonality in the crystal structure after sulfurization. The increments in the remnant (~34.8%) and saturated (~30.6%) polarizations of sulfurized BaTiO3 films were obtained in comparison with pure BaTiO3 films. Our work could be a primary study for a thorough understanding of the sulfur doping effect in perovskite oxides, opening up the potential of oxysulfide materials. [ABSTRACT FROM AUTHOR]

Chalcogenide perovskites are promising lead-free, stable absorber materials for solar cells. This work reports the synthesis of orthorhombic phase pure CaSnS3 thin films by facile low temperature sulfurization of solution-processed CaSnO3 oxide precursors. Structural characterization confirms complete anion exchange to produce crystalline CaSnS3 films with vertically aligned rod-like grains. Optical studies show strong visible light absorption with direct bandgap of 1.72 eV, ideal for photovoltaics. Electrical measurements indicate p-type conductivity with hole concentration of 1.2×1017 cm-3 and mobility around 8 cm2V-1s-1 at room temperature. First-principles DFT calculations corroborate the p-type electronic structure. Prototype CaSnS3 solar cells are fabricated with TiO2 electrode, demonstrating power conversion efficiency of 2.5% under AM1.5G, open-circuit voltage of 0.55 V, short circuit current density of 11.5 mA/cm² and fill factor of 0.62. The cells also exhibit remarkable ambient shelf stability over 6 months. The comprehensive results validate the photovoltaic potential of these earth abundant, sustainable chalcogenide perovskites synthesized via scalable low-cost solution methods. Further interface engineering can enable enhanced efficiencies. [ABSTRACT FROM AUTHOR]

We report the synthesis, characterizations, and hydrogen gas sensing of pure and silver (Ag)-doped bismuth sulfide (Bi2S3) nanobelts. The economical synthesis of Bi2S3 was carried out by the sulfurization of bismuth oxide (Bi2O3) using conventional solid-state reaction method. X-ray diffraction and scanning electron microscopy confirmed the synthesis of pure and silver-doped Bi2S3 nanobelts. Hydrogen gas sensing was studied at room temperature through current–voltage (I–V) characteristics. The percentage response of pure Bi2S3 nanobelts was 4.10%, whereas 2.5% silver-doped Bi2S3 showed a response of 24.01% at 26.66 kPa of H2 pressure. Response and recovery times were also analyzed from the dynamic response curves. Pure Bi2S3 nanobelts showed a response time of 8 s and recovery time of 20.4 s, whereas 2.5% silver-doped Bi2S3 nanobelts showed a response time of 6 s and recovery time of 15.2 s. The silver doping improved the reproducibility, selectivity, and stability of the sensor. [ABSTRACT FROM AUTHOR]

Abstract Emerging freestanding membrane technologies, especially using inorganic thermoelectric materials, demonstrate the potential for advanced thermoelectric platforms. However, using rare and toxic elements during material processing must be circumvented. Herein, we present a scalable method for synthesizing highly crystalline CuS membranes for thermoelectric applications. By sulfurizing crystalline Cu, we produce a highly percolated and easily transferable network of submicron CuS rods. The CuS membrane effectively separates thermal and electrical properties to achieve a power factor of 0.50 mW m−1 K−2 and thermal conductivity of 0.37 W m−1 K−1 at 650 K (estimated value). This yields a record‐high dimensionless figure‐of‐merit of 0.91 at 650 K (estimated value) for covellite. Moreover, integrating 12 CuS devices into a module resulted in a power generation of ~4 μW at ΔT of 40 K despite using a straightforward configuration with only p‐type CuS. Furthermore, based on the temperature‐dependent electrical characteristics of CuS, we develop a wearable temperature sensor with antibacterial properties.

Considering the increasing need for sustainable and economical energy storage solutions, the integration of layered materials such as MoS2 into these systems represents an important step toward enhancing energy sustainability and efficiency. Exploring environmentally responsible fabrication techniques, this study assesses wrinkled MoS2 thin films synthesized from distinct Mo and MoS2 targets, followed by sulfurization conducted in a graphite box. We utilized magnetron sputtering to deposit precursor Mo and MoS2 films on Si substrates, achieving thicknesses below 20 nm. This novel approach decreases sulfur by up to tenfold during sulfurization due to the confined space technique, contributing also to avoiding the formation of toxic gases such as SO2 or the necessity of using H2S, aligning with sustainable materials development. Thinner MoS2 layers were obtained post-sulfurization from the MoS2 precursors, as shown by X-ray reflectometry. Raman spectroscopy and grazing X-ray diffraction analyses confirmed the amorphous nature of the as-deposited films. Post-sulfurization, both types of films exhibited crystalline hexagonal MoS2 phases, with the sulfurized Mo showing a polycrystalline nature with a (100) orientation and sulfurized MoS2 displaying a (00L) preferred orientation. The X-ray photoelectron spectroscopy results supported a Mo:S ratio of 1:2 on the surface of the films obtained using the MoS2 precursor films, confirming the stoichiometry obtained by means of energy dispersive X-ray spectroscopy. Scanning electron microscopy and atomic force microscopy images revealed micrometer-sized clusters potentially formed during rapid cooling post-sulfurization, with an increased average roughness. These results open the way for the further exploration of wrinkled MoS2 thin films in advanced energy storage technologies. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The conversion of chalcogen atoms into other types of chalcogen atoms in transition metal dichalcogenides exhibits significant advantages in tuning the bandgaps and constructing lateral heterojunctions. However, despite atomic defects at the atomic scale were inevitably formed during conversion process, the construction of dislocations remains difficult. Here, we conducted in-situ sulfurization to achieve structural transformation from monolayer WSe 2 to WS 2 successfully. We probe these transformations at atomic scale using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and study structural defects of sulfurized-WS 2 by strain and displacement fields. We discovered that high-quality WSe 2 flakes were completely sulfurized while dislocations were successfully constructed, manifesting atomic surface roughness and structural disorders. Our work provides insights into designing and optimizing customized Transition metal dichalcogenides (TMDs) materials in controlled synthesis and defect engineering. [ABSTRACT FROM AUTHOR]

In recent years, antimony sulfide (Sb2S3) has been investigated as a photovoltaic absorber material due to its suitable absorber coefficient, direct band gap, extinction coefficient, earth-abundant, and environmentally friendly constituents. Therefore, this work proposes Sb2S3 film preparation by an effective two-step process using a new graphite box design and sulfur distribution, which has a high repeatability level and can be scalable. First, an Sb thin film was deposited using the RF-Sputtering technique, and after that, the samples were annealed with elemental sulfur into a graphite box, varying the sulfurization time from 20 to 50 min. The structural, optical, morphological, and chemical characteristics of the resulting thin films were analyzed. Results reveal the method's effectivity and the best properties were obtained for the sample sulfurized during 40 min. This Sb2S3 thin film presents an orthorhombic crystalline structure, elongated grains, a band gap of 1.69 eV, a crystallite size of 15.25 Å, and a nearly stoichiometric composition. In addition, the formation of a p-n junction was achieved by depositing silver back contact on the Glass/FTO/CdS/Sb2S3 structure. Therefore, the graphite box design has been demonstrated to be functional to obtain Sb2S3 by a two-step process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Almaty Technological University is the property of Almaty Technological University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the past decade, antimony selenide (Sb2Se3) has made significant progress as a solar energy conversion material. However, the photovoltage deficit continues to pose a challenge and is a major hurdle that must be overcome to reach its maximum solar conversion efficiency. In this study, various post‐synthetic treatments are employed, of which the combination of a solution phase silver nitrate treatment and sulfurization has shown to be the most effective approach to mitigate the photovoltage deficit in this Sb2Se3‐based device. A significant enhancement in the photovoltage is observed after the treatments, as evident by the increase in the onset potential from 0.18 to 0.40 V versus reversible hydrogen electrode. Multiwavelength Raman shows that combining these two treatments removes amorphous Se and metallic Sb from the surface and yields a high‐quality surface layer of Sb2(S1−x, Sex)3 on the bulk Sb2Se3 photoabsorber layer. X‐ray photoelectron spectroscopy with depth profiling reveals extensive incorporation of silver into the film. Density functional theory calculations suggest that silver ions can intercalate between the [Sb4Se6]n ribbons and remain in the Ag+ state. This effective treatment combination brings the practicality of the Sb2Se3 photocathode for water splitting one step closer to large‐scale applications. [ABSTRACT FROM AUTHOR]

Although in‐plane heterostructure with high ion transport pathway and unique interfacial atomic structure offers endless possibilities in the catalysis field, it is still challenging to directly synthesize MXene‐based in‐plane heterostructure due to the differences in crystal structures and growth conditions. Here, Mo2C–MoS2 in‐plane multi‐heterostructures are synthesized by topological conversion of sandwich‐like mesoporous Mo2C–SiO2 layers in sulfur vapor and subsequent removal of SiO2. During the conversion process, the exposed Mo2C will efficiently converted to 2H phase MoS2, meanwhile, the covered Mo2C remained stable, affording metallic Mo2C MXene and semiconducting MoS2 in‐plane multi‐heterostructures compatible in one layer. The resultant Mo2C–MoS2 layer has multiple heterointerfaces, build‐in electric fields as well as abundant defects. Such structural features enable to improve of the electrochemical active surface area (16.4 mF cm−2), which not only facilitates the bidirectional sulfur electrochemistry between solid Li2S and soluble lithium polysulfides, but also enhances the transfer kinetics of electrons and ions, giving rise to a high‐rate performance (642 mAh g−1 at 5 C) and a long‐term cycle life (1000 cycles at 5 C) in lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

In the quest for advanced materials suitable for next-generation electronic and optoelectronic applications, tungsten disulfide (WS2) ultrathin films have emerged as promising candidates due to their unique properties. However, obtaining WS2 directly on the desired substrate, eliminating the need for transfer, which produces additional defects, poses many challenges. This paper aims to explore the synthesis of WS2 ultrathin films via physical vapor deposition (PVD) followed by sulfurization in a confined space, addressing the challenge of film formation for practical applications. Precursor layers of tungsten and WS2 were deposited by RF magnetron sputtering. Subsequent sulfurization treatments were conducted in a small, closed, graphite box to produce WS2 films. The physical and chemical properties of these precursor and sulfurized layers were thoroughly characterized using techniques such as X-ray reflectometry (XRR), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The findings reveal notable distinctions in film thickness, structural orientation, and chemical composition, attributable to the different precursor used. Particularly, the sulfurized layers from the tungsten precursor exhibited a preferred orientation of WS2 crystallites with their (00L) planes parallel to the substrate surface, along with a deviation from parallelism in a small angular range. This study highlights the necessity of precise control over deposition and sulfurization parameters to tailor the properties of WS2 films for specific technological applications. [ABSTRACT FROM AUTHOR]

In the quest for advanced materials suitable for next-generation electronic and optoelectronic applications, tungsten disulfide (WS2) ultrathin films have emerged as promising candidates due to their unique properties. However, obtaining WS2 directly on the desired substrate, eliminating the need for transfer, which produces additional defects, poses many challenges. This paper aims to explore the synthesis of WS2 ultrathin films via physical vapor deposition (PVD) followed by sulfurization in a confined space, addressing the challenge of film formation for practical applications. Precursor layers of tungsten and WS2 were deposited by RF magnetron sputtering. Subsequent sulfurization treatments were conducted in a small, closed, graphite box to produce WS2 films. The physical and chemical properties of these precursor and sulfurized layers were thoroughly characterized using techniques such as X-ray reflectometry (XRR), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The findings reveal notable distinctions in film thickness, structural orientation, and chemical composition, attributable to the different precursor used. Particularly, the sulfurized layers from the tungsten precursor exhibited a preferred orientation of WS2 crystallites with their (00L) planes parallel to the substrate surface, along with a deviation from parallelism in a small angular range. This study highlights the necessity of precise control over deposition and sulfurization parameters to tailor the properties of WS2 films for specific technological applications.

This study focused on the synthesis and characterization of CZTS thin films using a spray pyrolysis method followed by sulfurization. Three different samples were prepared by varying the molar ratios of zinc to tin: Cu2ZnSnS4 (PV), Cu2Zn0.9Sn1.1S4 (NC), and Cu2Zn1.1Sn0.9S4 (PC). The samples were annealed in the presence of sulfur at 300℃. X-ray diffraction (XRD) analysis revealed the formation of a kesterite crystal structure in all samples, with the (112) plane being the dominant orientation. The CZTS thin films showed a maximum crystallite size of 11.6 nm in the PC sample. Field emission scanning electron microscopy (FESEM) was used to investigate the morphological properties, providing insights into the surface characteristics and microstructure of the thin films. The optical properties of the CZTS thin films were examined using UV-Vis spectroscopy. It was observed that the band gap energy increased in all samples after sulfurization, ranging from 1.50 eV to 1.66 eV. This indicates the potential suitability of the films as absorber layers in solar cell applications. The electrical properties were evaluated through Hall effect measurements, which revealed that the CZTS thin films exhibited p-type conductivity. The NC sample demonstrated the lowest specific resistivity of 1.43 Ω.cm.

The addition of flexible Cu2ZnSnS4 (CZTS) thin film solar cells to titanium (Ti) substrates is an attractive way to achieve the low-cost manufacturing of photovoltaics. Prior research has indicated that the appropriate diffusion of Ti elements can enhance the crystalline growth of CZTS films. However, the excessive diffusion of Ti has been shown to adversely affect the photovoltaic performance of CZTS photovoltaic devices. Therefore, it is essential to regulate the diffusion of Ti elements within CZTS thin films to optimize their photovoltaic properties. The tendency for Ti substrate elements to diffuse into CZTS films is also influenced by the activation energy associated with these Ti elements. The sulfurization temperature is posited to be a critical factor in modulating the diffusion and activation energy of Ti elements within CZTS thin films. Consequently, this research investigates the alteration of the sulfurization temperature of CZTS thin films in order to enhance the properties of these thin films and to examine the diffusion behavior of titanium elements. The results reveal that as the sulfurization temperature increases, the diffusion of Ti elements within the CZTS thin films initially increases, then decreases, and subsequently increases again. This pattern suggests that the diffusion of Ti elements is affected not only by the activation energy of the Ti elements but also by the defect hopping distance within the CZTS thin films. Notably, at a sulfurization temperature of 550 °C, the grains at the base of the CZTS thin film demonstrate an increased density, which is associated with a reduced defect hopping distance, thereby hindering the diffusion of Ti elements within the CZTS thin films. Furthermore, at this specific sulfurization temperature, the slope of the current–voltage (I–V) curve for the CZTS/Ti structure reaches its maximum, indicating optimal ohmic contact characteristics.

In the pursuit of highly active electrocatalysts is crucial to overcome the sluggish kinetics of oxygen evolution reaction (OER). Herein, Fe–CoS 2 /carbon nanotubes anchored on carbon polyhedron (Fe–CoS 2 /CNT CPs) is prepared by using zeolitic imidazolate framework-8@zeolitic imidazolate framework-67 (ZIF-8@ZIF-67) as template. A series of analysis demonstrates the incorporation of Fe via wrapped Fe-EDTA can exert charge transfer between Co and Fe and optimize the adsorption of targeted intermediates, which favors for enhanced OER performance. Moreover, the catalytic effect of Co and Fe not only promotes the growth of carbon nanotubes but also enhances the degree of graphitization. The carbon skeletons embedded with carbon nanotubes derived from ZIF-8@ZIF-67 offer high specific surface area and strengthen the electrical conductivity of Fe–CoS 2 /CNT CPs. Therefore, compared with its counterpart and commercial RuO 2 , the designed Fe–CoS 2 /CNT CPs with regulated electronic structure displays the lowest overpotential of 293 mV at the current density of 10 mA cm−2 in 1.0 M KOH solution for OER. This work explores a facile strategy for manipulate electronic structure and electrical conductivity of metal-organic frameworks derived catalysts simultaneously for robust OER electrocatalysts. • Fe–CoS 2 /CNT CPs is prepared by template assisted method. • The catalytic effect of Co and Fe facilitates the growth of carbon nanotubes. • The charge transfer between Co and Fe optimizes the adsorption of intermediates. • Carbon nanotubes along with carbon skeleton offer electron transport channels. • Fe–CoS 2 /CNT CPs exhibits superior OER activity with the overpotential of 293 mV. [ABSTRACT FROM AUTHOR]

Developing catalysts with superior activity to hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is equally important to the overall photoelectrochemical water splitting to produce hydrogen. In this work, bismuth oxyiodide (BiOI), iron-modified bismuth iodide Fe/BiOI, and the sulfurized S-Fe/BiOI were prepared using the solvothermal method. The three materials all have good absorption ability for visible light. The photoelectrochemical catalytic activity of BiOI to oxygen evolution reaction (OER) is significantly enhanced after iron modification, while the sulfurized product S-Fe/BiOI exhibits better catalytic activity to hydrogen evolution reaction (HER). Hence, OER and HER can be simultaneously catalyzed by using Fe/BiOI and S-Fe/BiOI as anodic and cathodic catalysts to facilitate the overall photoelectrochemical water splitting process. [ABSTRACT FROM AUTHOR]

MoS2 is a two-dimensional layered transition metal dichalcogenide with unique electronic and optical properties. The fabrication of ultrathin MoS2 is vitally important, since interlayer interactions in its ultrathin varieties will become thickness-dependent, providing thickness-governed tunability and diverse applications of those properties. Unlike with a number of studies that have reported detailed information on direct bandgap emission from MoS2 monolayers, reliable experimental evidence for thickness-induced evolution or transformation of the indirect bandgap remains scarce. Here, the sulfurization of MoO3 thin films with nominal thicknesses of 30 nm, 5 nm and 3 nm was performed. All sulfurized samples were examined at room temperature with spectroscopic ellipsometry and photoluminescence spectroscopy to obtain information about their dielectric function and edge emission spectra. This investigation unveiled an indirect-to-indirect crossover between the transitions, associated with two different Λ and K valleys of the MoS2 conduction band, by thinning its thickness down to a few layers. [ABSTRACT FROM AUTHOR]

The substance Ag3SbS3 could be a viable option guaranteeing extraordinary performance for electrodes with high storage capacity, but also for solar cell absorbents. For optimal manufacturing, Ag3SbS3 thin films were electrodeposited on Fluorine-Tin Oxide (FTO) and then sulfurized at different temperatures. Structurally, XRD and RAMAN analyses confirmed that hexagonal polycrystallization of the Ag3SbS3 phase is only effective for sulfurization at 475 °C. After elaboration, the thin films were analyzed morphologically, optically and electrochemically to better define their physicochemical performances. Cyclic voltammetry (CV) analysis proved that the co-electrodeposited Ag3SbS3/FTO electrode has a pseudo-capacitor behavior in Li2CO3 (0.5 M) under the [− 700, 0 mV] potential window, developing a specific capacitance of more than 810 F/g. Furthermore, the galvanostatic charge–discharge (GCD) confirms this pseudo-capacitor behavior and that by varying the current from 1 to 5 mA, the specific energy decreases slightly from 14.5 to 11.1 Wh kg−1 to the inverse of the specific power, which varies from 175.1 to 875.3 W. k g−1. Finally, the DFT calculation executed within the framework of generalized gradient approximation (GGA) with a modified Becke-Johnson exchange–correlation potential (mBJ) predicts results extremely comparable to those discovered experimentally and which are precisely an optical gap and an absorption coefficient of the order of 105 cm−1 and 1.62 eV, respectively. All of this enabled us to conclude that Ag3SbS3 possesses the physicochemical characteristics to make it an attractive option in the disciplines of supercapacity as well as photovoltaic. [ABSTRACT FROM AUTHOR]

Supercapacitors have emerged as a promising energy storage technology with attributes like high power and tuneable energy density along with splined cyclic potential. Their performance is heavily driven by the employed electrode materials that still crave high charge storage and rate capabilities as well as virile conductivity. Among numerous applied strategies to patch the corresponding quandary, sulfurization has garnered significant attention as an effective method for improving the electrochemical depiction of electrode materials. This review article presents a comprehensive analysis of the sulfurization process applied to the electrode with the aim of providing profound overview of the latest developments, the impact of sulfur incorporation on electrode properties, and the resulting performance enhancement in supercapacitors. It explores the influence of sulfidation on the morphological, structural, and compositional aspects of electrode materials, highlighting the modification of surface area, pore size distribution, crystal structure, and the formation of active sites. The discussions on the improved specific capacitance, enhanced rate capability, prolonged cycle life, and upgraded energy density achieved are accumulated. Additionally, the review explores the challenges and limitations associated with sulfurization and strategies to mitigate trials for future directions of research and developments. [ABSTRACT FROM AUTHOR]

This study focused on the synthesis and characterization of CZTS thin films using a spray pyrolysis method followed by sulfurization. Three different samples were prepared by varying the molar ratios of zinc to tin: Cu2ZnSnS4 (PV), Cu2Zn0.9Sn1.1S4 (NC), and Cu2Zn1.1Sn0.9S4 (PC). The samples were annealed in the presence of sulfur at 300°C. X-ray diffraction (XRD) analysis revealed the formation of a kesterite crystal structure in all samples, with the (112) plane being the dominant orientation. The CZTS thin films showed a maximum crystallite size of 11.6 nm in the PC sample. Field emission scanning electron microscopy (FESEM) was used to investigate the morphological properties, providing insights into the surface characteristics and microstructure of the thin films. The optical properties of the CZTS thin films were examined using UV-Vis spectroscopy. It was observed that the band gap energy increased in all samples after sulfurization, ranging from 1.50 eV to 1.66 eV. This indicates the potential suitability of the films as absorber layers in solar cell applications. The electrical properties were evaluated through Hall effect measurements, which revealed that the CZTS thin films exhibited p-type conductivity. The NC sample demonstrated the lowest specific resistivity of 1.43 Ω.cm. [ABSTRACT FROM AUTHOR]

Thin films composed of Cu3BiS3 have shown significant promise as light-harvesting materials because of their suitable optoelectronic properties and abundant, non toxic constituent elements. A large-grained, highly crystalline Cu3BiS3 films is a prerequisite for application of these layers in solar cells. We have grown large-grained, highly crystalline Cu3BiS3 films by a two-stage process via thermally evaporating Cu/Bi/Cu metallic layers and sulfurization at 400 °C for 30 min. The influence of the Cu/Bi ratio on the growth of Cu3BiS3 thin films was investigated by varying the Bi precursor thickness. The Cu/Bi ratio significantly influenced the structural, microstructural, optical, and electrical properties of Cu3BiS3 thin films. The Cu3BiS3 film synthesized with a Cu/Bi ratio of 4.35 contained Cu1.8S spurious phase, a non-uniform grain morphology, a direct optical bandgap of 1.41 eV, and an electrical resistivity of 75.5 Ωcm. Upon decreasing the Cu/Bi ratio from 3.38 to 2.77, the Cu1.8S spurious phase was eliminated, and phase-pure Cu3BiS3 was crystallized with a uniform grain morphology, particle size of 2–4 μm, direct bandgap of 1.42 eV, and electrical resistivity of 53.5 Ωcm. A further decrease in the Cu/Bi ratio from 2.77 to 2.54 resulted in a slight decrease in the grain size and electrical resistivity of the Cu3BiS3 films. This study demonstrates that Cu3BiS3 films synthesized with near-stoichiometric composition possess better structural, microstructural, optical, and electrical properties than those synthesized with Cu-rich composition and are suitable for use as solar cell absorber layer.

Organic matter (OM) sulfurization can enhance the preservation and sequestration of carbon in anoxic sediments, and it has been observed in sinking marine particles from marine O2-deficient zones. The magnitude of this effect on carbon burial remains unclear, however, because the transformations that occur when sinking particles encounter sulfidic conditions remain undescribed. Here, we briefly expose sinking marine particles from the eastern tropical North Pacific O2-deficient zone to environmentally relevant sulfidic conditions (20°C, 0.5 mM [poly]sulfide, two days) and then characterize the resulting solid-phase organic and inorganic products in detail. During these experiments, the abundance of organic sulfur in both hydrolyzable and hydrolysis-resistant solids roughly triples, indicating extensive OM sulfurization. Lipids also sulfurize on this timescale, albeit less extensively. In all three pools, OM sulfurization produces organic monosulfides, thiols, and disulfides. Hydrolyzable sulfurization products appear within ≤ 200-μm regions of relatively homogenous composition that are suggestive of sulfurized extracellular polymeric substances (EPS). Concurrently, reactions with particulate iron oxyhydroxides generate low and fairly uniform concentrations of iron sulfide (FeS) within these same EPS-like materials. Iron oxyhydroxides were not fully consumed during the experiment, which demonstrates that organic materials can be competitive with reactive iron for sulfide. These experiments support the hypothesis that sinking, OM- and EPS-rich particles in a sulfidic water mass can sulfurize within days, potentially contributing to enhanced sedimentary carbon sequestration. Additionally, sulfur-isotope and chemical records of organic S and iron sulfides in sediments have the potential to incorporate signals from water column processes.

A brief review of research publications that use the original concept first proposed by Academician B.A. Trofimov is presented. The concept consists in deep sulfurization of available industrial polymers and monomers in order to obtain high-sulfur organic compounds promising for the development of effective electrochemically active cathode materials. [ABSTRACT FROM AUTHOR]

We present the results of the study of the microstructure, X-ray diffraction and Raman scattering spectra of Cu2SnS3 (CTS) films synthesized at 500 °C by the sulfurization of Sn-Cu stacked metal precursors with different annealing time. The results indicate that sulfurization time has a great influence on both composition and morphology of the film. It is shown that the process of formation of a single-phase CTS compound with a monoclinic structure and composition close to stoichiometry is completed for a synthesis time of 60 - 80 min. With an increase in the time of synthesis to 120 min, the preservation of the monoclinic structural modification of the material is observed, accompanied by a shift in the stoichiometric composition, namely copper enrichment, material delamination and degradation of microstructural characteristics. As a result, it was found that the most optimal conditions for the synthesis of a single-phase Cu2SnS3 compound of a monoclinic structure are the temperature 500 °C with the duration of the sulfurization process from 60 to 80 min. [ABSTRACT FROM AUTHOR]

Wittichenite Cu3BiS3 thin films have received significant interest as light harvesters owing to their suitable optoelectronic properties and presence of earth-abundant, and non-toxic elements. We have synthesized Cu3BiS3 thin films by a two-stage process; in which, Cu/Bi/Cu metallic stacks were thermally evaporated and then sulfurized at 400 °C for 10-60 min in a quartz tubular furnace. The influence of sulfurization time on the structural, microstructural, compositional, optical, and electrical properties of the films was investigated. The results revealed that the films were orthorhombic Cu3BiS3 with the following lattice parameters: a = 0.768 nm; b = 1.043 nm; and c = 0.674 nm. Films uniformity, compactness, and crystal grain size increased upon increasing the sulfurization duration. On increasing the sulfurization time, the elemental stoichiometry of the films improved, and the direct optical bandgap increased from 1.38 to 1.40 eV. Additionally, Cu3BiS3 films exhibited p-type electrical conductivity and the electrical resistivity decreased with the increasing sulfurization time. Consequently, the Cu3BiS3 films synthesized at 30- and 60-min sulfurization durations can be applied to thin-film solar cells. [ABSTRACT FROM AUTHOR]

Optical properties of 1D nanocrystals of cadmium sulfide synthesized by vapor– liquid–solid growing were investigated as the function from such technological parameter as overpressure of sulfur vapor at the synthesis process or post-processing by the additional annealing in the sulfur atmosphere (sulfurization). The analyses of UV-vis absorption and photoluminescence spectra indicate considerable dependences of CdS nanocrystals optical parameters from sulfur compensation degree at the synthesis process. The photoluminescence spectra are characterized by changing the ratio of intensities of the defect level and near band edge emissions at overpressure sulfur vapor treatment. A significant decrease in the intensity of defect level emission after the growth or post-growth treatment in sulfur vapor has been observed. Optical absorption edge calculated using the Tauc relation demonstrates improvement of the crystal structure, which is reflected by the rising optical band gap value that approaches to the value for the bulk material at curing of sulfur vacancies by different technological ways. Optical properties obtained by absorption and luminescent measurements demonstrate total correlation, which corresponds to applied technology. [ABSTRACT FROM AUTHOR]

In recent years, antimony sulfide (Sb2S3) has been investigated as a photovoltaic absorber material due to its suitable absorber coefficient, direct band gap, extinction coefficient, earth-abundant, and environmentally friendly constituents. Therefore, this work proposes Sb2S3 film preparation by an effective two-step process using a new graphite box design and sulfur distribution, which has a high repeatability level and can be scalable. First, an Sb thin film was deposited using the RF-Sputtering technique, and after that, the samples were annealed with elemental sulfur into a graphite box, varying the sulfurization time from 20 to 50 min. The structural, optical, morphological, and chemical characteristics of the resulting thin films were analyzed. Results reveal the method’s effectivity and the best properties were obtained for the sample sulfurized during 40 min. This Sb2S3 thin film presents an orthorhombic crystalline structure, elongated grains, a band gap of 1.69 eV, a crystallite size of 15.25 Å, and a nearly stoichiometric composition. In addition, the formation of a p-n junction was achieved by depositing silver back contact on the Glass/FTO/CdS/Sb2S3 structure. Therefore, the graphite box design has been demonstrated to be functional to obtain Sb2S3 by a two-step process.

Through surface nanocrystallization and low-temperature ion sulfurization, the nanocrystalline/FeS thin film with excellent friction-reduction and antiwear properties was fabricated on the surface of AISI321 stainless steel. The nanocrystallization treatment formed the high hardness and active nanocrystalline structure on the surface of AISI321, with the harness increased from 4.6 GPa to 7.56 GPa. Furthermore, the significantly refined nanostructure strongly increased the concentration of S element in comparison with the single-sulfurized layer on the substrate. Tribological tests reveal that both the original AISI321 substrate and the single-sulfurizing-treated samples are subject to severe abrasion. Single nanocrystallization treatment can improve the wear resistance of AISI321, while the compound treatment can obviously improve the comprehensive tribological properties. The compound-modified layer presents excellent tribological properties with the lowest coefficient of friction (COF) of 0.33, which is related to the increased hardness of the substrate and increased thickness, density, and homogeneity of the sulfurized layer. Furthermore, a physical model is developed for the vacuum tribological behavior of the samples after different treatments. This model provides a reference for revealing the tribological mechanism of the compound-modified layer treated using surface nanocrystallization-assisted chemical heat treatment. [ABSTRACT FROM AUTHOR]

With the overconsumption of disposable plastics, there is a considerable emphasis on the recycling of waste plastics to relieve the environmental, economic, and health‐related consequences. Here, a sulfur‐assisted pyrolysis strategy is demonstrated for versatile upcycling of plastics into high‐value carbons with an ultrahigh carbon‐atom recovery (up to 85%). During the pyrolysis process, the inexpensive elemental sulfur molecules are covalently bonded with polymer chains, and then thermally stable intermediates are produced via dehydrogenation and crosslinking, thereby inhibiting the decomposition of plastics into volatile small hydrocarbons. In this manner, the carbon products obtained from real‐world waste plastics exhibit sulfur‐rich skeletons with an enlarged interlayer distance, and demonstrate superior sodium storage performance. It is believed that the present results offer a new solution to alleviate plastic pollution and reduce the carbon footprint of plastic industry. [ABSTRACT FROM AUTHOR]

Sulfide precipitation has been widely applied to remove arsenic from acidic wastewater containing As(III) and As(V), due to its simple process and high efficiency. However, the characteristics and composition of the precipitates are also of importance for its further treatment and disposal. To explore the characteristics of elemental S formed by reduction and the combined form of the generated S and As2S3, the characteristics of precipitates sulfurized from As(III) and As(V) and the effects of temperature, the S(-II) to As ratio (S/As), Cl− concentration (cCl−), and the volume fraction of H2SO4 (φH2SO4(v)) on the sulfurization of As(III) and As(V) were investigated in detail. The results showed that the contents of As and S were 60.37% and 39.73% in precipitate-As(III), while they accounted for 47.46% and 52.64% in precipitate-As(V); both precipitate-As(III) and precipitate-As(V) were mainly composed of amorphous As2S3, while the latter contained elemental S. Temperature and S(-II)/As(III) slightly affected the sulfurization process of As(III), while for As(V), as the temperature increased, the content of As2S3 in precipitate-As(V) increased significantly. Additionally, with the S(-II)/As(V) increasing, the content of A2S3 increased continuously. This study provides a further clarification of the specific composition and structure of the complex precipitates of arsenic sulfide, which will benefit the efficient stabilization of the arsenic sulfide sludge. [ABSTRACT FROM AUTHOR]

Mudstones from the Argiles de Châtillon Formation exposed in the Boulonnais region of Northern France represent a proximal lateral equivalent of the organic-rich Kimmeridge Clay Formation. The Argiles de Châtillon Formation is composed of two subunits that straddle the Kimmeridgian–Tithonian boundary. Each subunit contains an organic-rich interval. The two conspicuous organic-rich intervals have been linked to either periods of high sea level or greenhouse warming. Here, we use palynology to further understand climate and environmental mechanisms that drove organic matter enrichment. We use bulk organic carbon isotope records (δ13Corg) to correlate the Boulonnais sections with those of the Kimmeridge Clay Formation. The palynological results suggest that the stratigraphically lower organic-rich interval (Kimmeridgian) was deposited under suboxic to anoxic stratified conditions. A large-scale climate shift from cooler/humid to warmer/arid conditions marked the Kimmeridgian–Tithonian boundary, influencing organic matter enrichment in the stratigraphically higher organic-rich interval (Tithonian). In contrast with the lower organic-rich interval, there are no indications of stratified conditions for the higher organic-rich interval. Within this thicker organic-rich interval, cyclic variations in amorphous organic matter distribution, total organic carbon and δ13Corg trends on a 2 m scale are observed. They co-occur with fluctuations of the palynological assemblages, indicative of more humid versus arid climate conditions, likely alternating on a ∼100 kyr eccentricity timescale. Our results show that under the most humid phases of these overall arid climate conditions, sulfurization of carbohydrates was the dominant control on organic matter preservation. This climate-controlled process that drives organic matter enrichment in the Tithonian can be recognized on a basin-wide scale. [ABSTRACT FROM AUTHOR]

A study has been carried out to investigate the influence of the amount of Sn in the precursor solution, on some physical properties of CZTS films grown by sulfurization of electrodeposited metallic precursors. The growth of the CZTS samples was achieved by sequential electrodepositon of constituent metallic layers on ITO glass substrates using a 3-electrode electrochemical cell with graphite as a counter electrode and Ag/AgCl as the reference electrode. The Sn-content in the metallic precursor was varied by varying the deposition time of Sn. The stacked elemental layer was then soft annealed in Argon at 350 °C, and subsequently sulfurized at 550° C to grow the CZTS thin films. The structure, morphology and optical properties were investigated. X-ray diffraction studies revealed that, irrespective of the Sn content all the films were polycrystalline and exhibited the Kesterite CZTS structure with preferred orientation along the (112) plane. However, there was an increase in the amount of peaks indexed to the undesirable secondary phases, as the Sn content in metallic precursor was increased. Optical absorption measurements revealed the existence of a direct transition with band gap values decreasing from 1.74 eV to 1.25 eV with increasing amounts of Sn. The lower value for the band gap was attributed to the presence of secondary phases formed in addition to the CZTS film. Morphology of the sulfurized films showed a compact and rocky texture with good coverage across the entire substrate. However, CZTS films with a higher Sn content appeared to have a molten metallic surface with deep cracks which could have adverse effects on the electrical properties of the film. EDAX analysis showed all the films were consistent with the formation of CZTS. It is evident from all the characterization techniques that increasing the Sn content of the stacked metallic precursors beyond stoichiometric amounts had an adverse effect on the structural and optical properties of CZTS films grown by this technique.

Recently, there has been an increase in the use of antimony sulfide (Sb _2 S _3 ) in Si-based tandem solar cells as a potential absorber material for top sub-cells. The choice of the material stems from the favoured properties such as appropriate bandgap, simple binary composition, nontoxic elements, and long-term stability. However, the physical properties and practical applicability of these materials depend largely on their synthesis conditions. In this work, we investigate the role of sulfurization on the structural, morphological, compositional, and optical properties of Sb _2 S _3 thin films deposited on soda-lime glass via a thermal evaporation technique. Sulfurization was performed on the as-prepared thin films in a customized Chemical Vapor Deposition (CVD) chamber at five different temperatures. Analysis of the crystallinity of the film using the x-ray diffraction technique illustrates the transformation of the film from impure, poor crystalline phase to phase-pure, and highly crystalline orthorhombic structure due to sulfurization. Scanning electron microscopic investigations of the samples revealed better grains with nanorods on the surface at a temperature of 400 °C. For the samples investigated here, the energy values estimated via density functional theory (DFT) calculations agreed well with the experimental data obtained from UV-visible absorption spectral studies. Additionally, it was observed that the desired near-stoichiometric Sb _2 S _3 thin films could be achieved via sulfurization, and the presence of Sb _2 S _3 in all samples was confirmed via Raman spectroscopic studies. Additionally, the defects and trap states of the prepared films were investigated using photoluminescence studies, and donor and acceptor defects were identified. Our study revealed that sulfur rich Sb _2 S _3 films prepared at a sulfurization temperature of 400 °C produced the desired structure, morphology, and optical qualities for future photovoltaic applications.

Developing catalysts with superior activity to hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is equally important to the overall photoelectrochemical water splitting to produce hydrogen. In this work, bismuth oxyiodide (BiOI), iron-modified bismuth iodide Fe/BiOI, and the sulfurized S-Fe/BiOI were prepared using the solvothermal method. The three materials all have good absorption ability for visible light. The photoelectrochemical catalytic activity of BiOI to oxygen evolution reaction (OER) is significantly enhanced after iron modification, while the sulfurized product S-Fe/BiOI exhibits better catalytic activity to hydrogen evolution reaction (HER). Hence, OER and HER can be simultaneously catalyzed by using Fe/BiOI and S-Fe/BiOI as anodic and cathodic catalysts to facilitate the overall photoelectrochemical water splitting process.

MoS2 is a two-dimensional layered transition metal dichalcogenide with unique electronic and optical properties. The fabrication of ultrathin MoS2 is vitally important, since interlayer interactions in its ultrathin varieties will become thickness-dependent, providing thickness-governed tunability and diverse applications of those properties. Unlike with a number of studies that have reported detailed information on direct bandgap emission from MoS2 monolayers, reliable experimental evidence for thickness-induced evolution or transformation of the indirect bandgap remains scarce. Here, the sulfurization of MoO3 thin films with nominal thicknesses of 30 nm, 5 nm and 3 nm was performed. All sulfurized samples were examined at room temperature with spectroscopic ellipsometry and photoluminescence spectroscopy to obtain information about their dielectric function and edge emission spectra. This investigation unveiled an indirect-to-indirect crossover between the transitions, associated with two different Λ and K valleys of the MoS2 conduction band, by thinning its thickness down to a few layers.

Abstract With the overconsumption of disposable plastics, there is a considerable emphasis on the recycling of waste plastics to relieve the environmental, economic, and health‐related consequences. Here, a sulfur‐assisted pyrolysis strategy is demonstrated for versatile upcycling of plastics into high‐value carbons with an ultrahigh carbon‐atom recovery (up to 85%). During the pyrolysis process, the inexpensive elemental sulfur molecules are covalently bonded with polymer chains, and then thermally stable intermediates are produced via dehydrogenation and crosslinking, thereby inhibiting the decomposition of plastics into volatile small hydrocarbons. In this manner, the carbon products obtained from real‐world waste plastics exhibit sulfur‐rich skeletons with an enlarged interlayer distance, and demonstrate superior sodium storage performance. It is believed that the present results offer a new solution to alleviate plastic pollution and reduce the carbon footprint of plastic industry.