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The environmental threat posed by stibnite is an important geoenvironmental issue of current concern. To better understand stibnite oxidation pathways, aerobic abiotic batch experiments were conducted in aqueous solution with varying δ18OH2O value at initial neutral pH for different lengths of time (15-300 days). The sulfate oxygen and sulfur isotope compositions as well as concentrations of sulfur and antimony species were determined. The sulfur isotope fractionation factor (Δ34SSO4-stibnite) values decreased from 0.8 to -2.1 during the first 90 days, and increased to 2.6 at the 180 days, indicating the dominated intermediate sulfur species such as S2O32-, S0, and H2S (g) involved in Sb2S3 oxidation processes. The incorporation of O into sulfate derived from O2 (â¼100%) indicated that the dissociated O2 was only directly adsorbed on the stibnite-S sites in the initial stage (0-90 days). The proportion of O incorporation into sulfate from water (27%-52%) increased in the late stage (90-300 days), which suggested the oxidation mechanism changed to hydroxyl attack on stibnite-S sites promoted by nearby adsorbed O2 on stibnite-Sb sites. The exchange of oxygen between sulfite and water may also contributed to the increase of water derived O into SO42-. The new insight of stibnite oxidation pathway contributes to the understanding of sulfide oxidation mechanism and helps to interpret field data.
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Oxirredução , Isótopos de Oxigênio , Sulfatos , Isótopos de Enxofre , Isótopos de Enxofre/análise , Sulfatos/química , Isótopos de Oxigênio/análise , Antimônio/química , Modelos Químicos , Aerobiose , Oxigênio/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , ÓxidosRESUMO
The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process, which is the first step of new particle formation (NPF). In the present study, cycloaddition reaction mechanism of sulfur trioxide (SO3) to hydrogen sulfide (H2S) which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code simulations. Gas-phase stability and nucleation potential of the product thiosulfuric acid (H2S2O3, TSA) were further analyzed to evaluate its atmospheric impact. Without any catalysts, the H2S + SO3 reaction is infeasible with a barrier of 24.2 kcal/mol. Atmospheric nucleation precursors formic acid (FA), sulfuric acid (SA), and water (H2O) could effectively lower the reaction barriers as catalysts, even to a barrierless reaction with the efficiency of cis-SA > trans-FA > trans-SA > H2O. Subsequently, the gas-phase stability of TSA was investigated. A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of TSA. Furthermore, topological and kinetic analysis were conducted to determine the nucleation potential of TSA. Atmospheric clusters formed by TSA and atmospheric nucleation precursors (SA, ammonia NH3, and dimethylamine DMA) were thermodynamically stable. Moreover, the gradually decreasing evaporation coefficients for TSA-base clusters, particularly for TSA-DMA, suggests that TSA may participate in NPF where the concentration of base molecules are relatively higher. The present new reaction mechanism may contributes to a better understanding of atmospheric sulfur cycle and NPF.
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Poluentes Atmosféricos , Sulfeto de Hidrogênio , Modelos Químicos , Sulfeto de Hidrogênio/química , Poluentes Atmosféricos/química , Reação de Cicloadição , Atmosfera/química , Óxidos de Enxofre/química , Cinética , Enxofre/químicaRESUMO
Regulating the adsorption of an intermediate on an electrocatalyst by manipulating the electron spin state of the transition metal is of great significance for promoting the activation of inert nitrogen molecules (N2) during the electrocatalytic nitrogen reduction reaction (eNRR). However, achieving this remains challenging. Herein, a novel 2D/2D Mott-Schottky heterojunction, Co9S8/Nb2CTx-P, is developed as an eNRR catalyst. This is achieved through the in situ growth of cobalt sulfide (Co9S8) nanosheets over a Nb2CTx MXene using a solution plasma modification method. Transformation of the Co spin state from low (t2g 6eg 1) to high (t2g 5eg 2) is achieved by adjusting the interface electronic structure and sulfur vacancy of Co9S8/Nb2CTx-P. The adsorption ability of N2 is optimized through high spin Co(II) with more unpaired electrons, significantly accelerating the *N2â*NNH kinetic process. The Co9S8/Nb2CTx-P exhibits a high NH3 yield of 62.62 µg h-1 mgcat. -1 and a Faradaic efficiency (FE) of 30.33% at -0.40 V versus the reversible hydrogen electrode (RHE) in 0.1 m HCl. Additionally, it achieves an NH3 yield of 41.47 µg h-1 mgcat. -1 and FE of 23.19% at -0.60 V versus RHE in 0.1 m Na2SO4. This work demonstrates a promising strategy for constructing heterojunction electrocatalysts for efficient eNRR.
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Detecting dopamine (DA) in biological samples is vital to understand its crucial role in numerous physiological processes, such as motion, cognition, and reward stimulus. In this work, p-type graphene on sapphire, synthesized via chemical vapor deposition, serves as substrate for the preparation of p-type Cu2-xS films through solid-phase sulfurization. The optimized Cu2-xS/graphene heterostructure, prepared at 250 °C using a 15-nm copper film sulfurized for 2 h, exhibits superior electron transfer performance, ideal for electrochemical sensing. It is confirmed that the spontaneous charge transfer from graphene to Cu2-xS, higher Cu(II)/Cu(I) ratio (~ 0.8), and the presence of well-defined nanocrystalline structures with an average size of ~ 35 nm in Cu2-xS significantly contribute to the improved electron transfer of the heterostructure. The electrochemical sensor based on Cu2-xS/graphene heterostructure demonstrates remarkable sensitivity towards DA, with a detection limit as low as 100 fM and a dynamic range greater than 109 from 100 fM to 100 µM. Additionally, it exhibits excellent selectivity even in the presence of uric acid and ascorbic acid 100 times higher, alongside notable storage and measurement stability and repeatability. Impressively, the sensor also proves capable of detecting DA concentrations as low as 100 pM in rat serum, showcasing its potential for clinically relevant analytes and promising applications in sensitive, selective, reliable, and efficient point-of-care diagnostics.
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Cobre , Dopamina , Técnicas Eletroquímicas , Grafite , Limite de Detecção , Dopamina/sangue , Dopamina/análise , Cobre/química , Grafite/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Animais , Ratos , Técnicas Biossensoriais/métodos , EletrodosRESUMO
Dairy products, such as whey proteins, have been effectively utilized to enhance the effectiveness of vitamin D fortification and optimize circulating 25(OH)VD levels. Whey protein is rich in L-cysteine (LC) which is the precursor of hydrogen sulfide (H2S), enhances glutathione (GSH) biosynthesis, and promotes positive nitrogen balance. Zucker diabetic rats (ZDF) were used as a model in this study, to examine the hypothesis that LC supplementation enhances blood levels of H2S and nitrite (NO2) while reducing inflammation biomarkers. Rats were gavaged daily (orally) with either saline placebo or L-cysteine along with a high-calorie diet starting at 6 weeks of age. Fasting blood levels showed LC supplementation significantly increased circulatory levels of H2S and NO2 compared with placebo rats. LC supplementation increased plasma concentration of 25(OH)VD and vitamin C and lowered leptin and body weight gain in ZDF rats. Furthermore, to assess the impact of H2S and NO2 in raising 25(OH)VD levels, the in vitro effect of H2S/NO2 on vitamin D metabolism genes was examined using THP-1 monocytes. The exogenous H2S and NO2 treatment upregulated the relative expression of CYP2R1 and CYP27B1 genes in cultured monocytes. This study suggests a potential mechanism for the observed increase in circulating 25(OH)VD levels following L-cysteine supplementation.
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BACKGROUND: Changes in K+ channel expression/function are associated with disruption of vascular reactivity in several pathological conditions, including hypertension, diabetes, and atherosclerosis. Gasotransmitters achieve part of their effects in the organism by regulating ion channels, especially K+ channels. Their involvement in hydrogen sulfide (H2S)-mediated vasorelaxation is still unclear, and data about human vessels are limited. OBJECTIVE: To determine the role of K+ channel subtypes in the vasorelaxant mechanism of H2S donor, sodium-hydrosulfide (NaHS), on isolated human internal mammary artery (HIMA). RESULTS: NaHS (1 × 10-6-3 × 10-3 mol/L) induced a concentration-dependent relaxation of HIMA pre-contracted by phenylephrine and high K+. Among K+ channel blockers, iberiotoxin, glibenclamide, 4-aminopyridine (4-AP), and margatoxin significantly inhibited NaHS-induced relaxation of phenylephrine-contracted HIMA (P < 0.01), whereas in the presence of apamin/1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) combination, the HIMA relaxation was partially reduced (P < 0.05). The effect of NaHS was antagonized by NO pathway inhibitors, L-NAME and KT5823, and by cyclo-oxygenase inhibitor, indomethacin (P < 0.01). Under conditions of blocked NO/prostacyclin synthesis and release, apamin/TRAM-34 and glibenclamide caused further decrease in NaHS-induced vasorelaxation (P < 0.01), while iberiotoxin, 4-AP, and margatoxin were without additional effect (P > 0.05). In the presence of nifedipine, NaHS induced partial relaxation of HIMA (P < 0.01). CONCLUSION: Our results demonstrated that H2S donor, NaHS, induced concentration-dependent relaxation of isolated HIMA. Vasorelaxant mechanisms of H2S included direct or indirect opening of different K+ channel subtypes, KATP, BKCa, SKCa/IKCa, and KV (subtype KV1.3), in addition to NO pathway activation and interference with extracellular Ca2+ influx.
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In this study, we conducted lab-scale experiments to assess the applicability of calcium polysulfide (CPS) for the removal of cadmium (Cd2+) and zinc (Zn2+) from acidic groundwater, with an emphasis on the injection ratio and removal mechanism. For the experiments, CPS was used to treat Cd2⺠and Zn2⺠contaminated solution. Solutions were purged with nitrogen gas, and CPS was injected in an anaerobic chamber. After 18 h, solutions were filtered, and heavy metal concentrations were measured using ICP-MS and ICP-OES. Total polysulfide (Sx2â») concentration in CPS was determined by converting it to bisulfide (HSâ») at pH 8.20 and quantifying via UV-Vis spectrophotometry. Precipitates were analyzed using XRD and SEM-EDS after centrifugation. The findings revealed that more than 99.5% of the heavy metals were removed when CPS/Cd2+ (w/w) = 1.45 and CPS/Zn2+ (w/w) = 2.50, determined as the injection ratios for maximum efficiency. These ratios were applicable when Cd2+ and Zn2+ coexisted. From the XRD and SEM-EDS analyses, it was clarified that Cd2+ and Zn2+ precipitated in sulfide forms, consistently showing the preferential precipitation of Cd2+ because of the lower solubility of cadmium sulfide compared to zinc sulfide. In addition, the concentration of Sx2- in the 29% CPS solution was determined to be approximately 2.442 M. Finally, by comparing the injected Sx2- concentration with the concentration of heavy metals removed accordingly, it was concluded that CPS and heavy metals react with a 1:1 M ratio. Based on the above results and precise quantification method, our study suggests that CPS can be effectively utilized to address heavy metal contamination issues and may serve as a valuable tool for the remediation and management of contaminated groundwater globally.
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Osteoporosis (OP), the most prevalent bone degenerative disease, has become a significant public health challenge globally. Current therapies primarily target inhibiting osteoclast activity or stimulating osteoblast activation, but their effectiveness remains suboptimal. This paper introduced a "three birds, one stone" therapeutic approach for osteoporosis, employing upconversion nanoparticles (UCNPs) to create a dual-gas storage nanoplatform (UZPA-CP) targeting bone tissues, capable of concurrently generating carbon monoxide (CO) and hydrogen sulfide (H2S). Through the precise modulation of 808 nm near-infrared (NIR) light, the platform could effectively control the release of CO and H2S in the OP microenvironment, and realize the effective combination of promoting osteogenesis, inhibiting osteoclast activity, and improving the immune microenvironment to achieve the therapeutic effect of OP. High-throughput sequencing results further confirmed the remarkable effectiveness of the nanoplatform in inhibiting apoptosis, modulating inflammatory response, inhibiting osteoclast differentiation and regulating multiple immune signaling pathways. The gas storage nanoplatform not only optimized the OP microenvironment with the assistance of NIR, but also restored the balance between osteoblasts and osteoclasts. This comprehensive therapeutic strategy focused on improving the bone microenvironment, promoting osteogenesis and inhibiting osteoclast activity provides an ideal new solution for the treatment of metabolic bone diseases.
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Hydrogen sulfide is a vital signaling molecule which holds a pivotal position in numerous biological functions. In this research, two novel "OFF-ON" fluorescence probes named YNO and TNO were designed based on the nitroso recognition group to detect H2S. Both YNO and TNO performed outstanding response rate and linear relationship between the fluorescence intensity and the concentration of H2S. YNO possessed larger Stokes shift and longer emission wavelength. TNO had lower limit of detection. In addition, YNO was successful applied to sense endogenous and exogenous H2S and target endoplasmic reticulum (ER) in Hela cells.
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Hydrogen sulfide (H2S), an endogenous gas transmitter, plays a key role in several critical physiological and pathological processes in vivo, including vasodilation, anti-infection, anti-tumor, anti-inflammation, and angiogenesis. In colorectal cancer (CRC), aberrant overexpression of H2S-producing enzymes has been observed. Due to the important role of H2S in the proliferation, growth, and death of cancer cells, H2S signaling pathways can serve as potential targets for cancer treatment. In this review, we thoroughly analyzed the underlying mechanism of action of H2S in CRC from the following aspects: the synthesis and catabolism of H2S in CRC cells and its effect on cell signal transduction pathway; the inhibition effect of exogenous H2S donors with different concentrations on the growth of CRC cells and the underlying mechanism of H2S in garlic and other natural products. Furthermore, we elucidate the expression characteristics of H2S in CRC and construct a comprehensive H2S-related signaling pathway network, which has important basic and practical significance for promoting the clinical research of H2S-related drugs.
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After understanding the biological signaling roles of hydrogen sulfide and its involvement in various physiological processes, there has been enormous interest in exploring its therapeutic utility in areas such as cancer, inflammation, cardiovascular diseases, etc. There is also growing interest in using suitable H2S donors in combination with other drugs to improve the treatment outcome through the modulation of multiple pathways. The premature release of H2S from small molecule donors and the difficulty in controlling its spatio-temporal distribution are the major challenges during these efforts. Hence the development of appropriate carriers that can release this gasotransmitter along with the therapeutic entity of interest in a controlled manner has high significance. In this regard, this report presents a novel drug delivery system from oxanorbornane-based synthetic lipids that carries a H2S-releasing 1,2-dithiole-3-thione moiety as part of the head group. Nanoaggregates of the resulting conjugate are not only capable of efficiently entrapping a non-steroidal anti-inflammatory drug such as ibuprofen, but also release this drug and H2S in a controlled and sequential manner.
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In recent years, catalysts based on transition metal sulfides have garnered extensive attention due to their low cost and excellent electrocatalytic activity in the alkaline oxygen evolution reaction. Here, the preparation of Fe-doped Ni3S2 via a one-step hydrothermal approach is reported by utilizing inexpensive transition metals Ni and Fe. In an alkaline medium, Fe-Ni3S2 exhibits outstanding electrocatalytic activity and stability for the OER, and the current density can reach 10 mA cm-2 with an overpotential of 163 mV. In addition, Pt/C||Fe-Ni3S2 is used as the membrane electrode of the anion exchange membrane water electrolyzer, which is capable of providing a current density of 650 mA cm-2 at a cell voltage of 2.0 V, outperforming the benchmark Ir/C. The principle is revealed that the doping of Fe enhances the electrocatalytic water decomposition ability of Ni3S2 by in situ Raman and in situ X-ray absorption fine structure. The results indicate that the doping of Fe decreases the charge density near Ni atoms, which renders Fe-Ni3S2 more favorable for the adsorption of OH- and the formation of *OO- intermediates. This work puts forward an effective strategy to significantly improve both the alkaline OER activity and stability of low-cost electrocatalysts.
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Hydrogen sulfide (H2S) has emerged as a potent therapeutic agent with diverse physiological functions, including vasodilation, anti-inflammation, and cytoprotection. However, its clinical application is limited due to its volatility and potential toxicity at high concentrations. To address these challenges, researchers have developed various H2S prodrugs that release H2S in a controlled and targeted manner. The review underscores the importance of targeting and delivery strategies in maximizing the therapeutic potential of H2S, a gasotransmitter with diverse physiological functions and therapeutic effects. By summarizing recent advancements, the review provides valuable insights for researchers and clinicians interested in harnessing the therapeutic benefits of H2S while minimizing off-target effects and toxicity. The integration of novel targeting and delivery approaches not only enhances the efficacy of H2S-based therapeutics but also expands the scope of potential applications, offering promising avenues for the development of new treatments for a variety of diseases and disorders.
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Faced with worldwide mercury (Hg) contamination in groundwater, efficient in situ remediation technologies are urgently needed. Carboxymethyl cellulose (CMC) stabilized iron sulfide (CMC-FeS) nanoparticles have been found effective for immobilizing mercury in water and soil. Yet, the potential use of the nanoparticles for creating an in situ reactive zone (ISRZ) in porous geo-media has not been explored. This study assessed the transport and deliverability of CMC-FeS in sand media towards creating an ISRZ. The nanoparticles were deliverable through the saturated sand bed and the particle breakthrough/deposition profiles depended on the injection pore velocity, initial CMC-FeS concentration, and ionic strength. The transport data were well interpreted using an advection-dispersion transport model combined with the classical filtration theory. The resulting ISRZ effectively removed mercury from contaminated groundwater under typical subsurface conditions. While the operating conditions are yet to be optimized, the Hg breakthrough time can be affected by groundwater velocity, influent mercury concentration, dissolved organic matter, and co-existing metals/metalloids. The one-dimensional advection-dispersion equation well simulated the Hg breakthrough data. CMC-FeS-laden ISRZ effectively converted the more easily available Hg species to stable species. These findings reveal the potential of creating an ISRZ using CMC-FeS for in situ remediation of Hg contaminated soil and groundwater.
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Photothermal therapy (PTT), particularly in the near-infrared-II (NIR-II) range, has attracted widespread attention over the past years. However, the accompanied inflammatory responses can result in undesirable side effects and contribute to treatment ineffectiveness. Herein, we introduced a novel biodegradable nanoplatform (CuS/HMON-PEG) capable of PTT and hydrogen sulfide (H2S) generation, aimed at modulating inflammation for improved cancer treatment outcomes. The embedded ultrasmall copper sulphide (CuS) nanodots (1-2â¯nm) possessed favorable photoacoustic imaging (PAI) and NIR-II photothermal capabilities, rendering CuS/HMON-PEG an ideal phototheranostic agent. Upon internalization by 4T1 cancer cells, the hollow mesoporous organosilica nanoparticle (HMON) component could react with the overproduced glutathione (GSH) to produce H2S. In addition to the anticipated photothermal tumor ablation and H2S-induced mitochondrial dysfunction, the anti-inflammatory regulation was also been demonstrated by the downregulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1beta (IL-1ß). More importantly, the modulation of inflammation also promoted wound healing mediated by PTT. This work not only presents a H2S-based nanomodulator to boost NIR-II PTT but also provides insights into the construction of novel organic/inorganic hybrid nanosystems.
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To develop a reliable sulfide (S2-) autotrophic denitrification (SAD) process under S2- and SO42- salinity stresses, the biofilm performance and microbial mechanisms were comparatively studied using different inocula of activated sludge (AS) and intertidal sediment (IS). Biofilm IS enriched more denitrification genes (0.34â¯%) and S2- oxidation genes (0.29â¯%) than those with AS. Higher denitrification performance was obtained under S2- (100â¯mg/L) and SO42- (5-15â¯g/L Na2SO4) stresses, but no significantly differences were observed under levels of 0-200â¯mg/L S2- and 30â¯g/L Na2SO4. Notably, biofilm samples in SAD systems with IS still had more S2- oxidation genes at high S2- levels of 100-200â¯mg/L and Na2SO4 level of 30 g/L. The key functional genus Thiobacillus accumulated well at 30 g/L Na2SO4, but was strongly inhibited at 200â¯mg/L S2-. The findings were advantage to SAD application under sulfide and salinity stresses.
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This work presents a new strategy to achieve the growth of copper sulfide nanoclusters with high nuclearity. Through a phosphine-assisted C-S reductive cleavage approach, an intrinsically chiral [Cu4] cluster passes through a [S-Cu9] cluster and transforms into a higher-nuclearity [S-Cu36] cluster, which features a core-shell structure with a [Cu4]4+ core encapsulated by a chiral [Cu20S12] shell. Interestingly, the spiral arrangement of the bidental ligands on the surface of the [S-Cu36] cluster leads to the L-/R-enantiomeric configurations. Moreover, by utilization of [Na(THF)6]+ as a chiral adaptive counterion, [S-Cu36] can be interlocked separately, thus enabling the isolation of homochiral clusters. Theoretical calculation suggests that the configuration transition between two enantiomeric [Na(THF)6]+ species is favorable at room temperature, thereby promoting the cocrystallization of resulting chiral products. This study introduces a novel perspective on the synthesis of chiral copper sulfide nanoclusters and presents an innovative approach to achieving the chiral separation of nanoclusters.
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The aroma is critical in the reproductive biology of truffles and in their commercial quality. However, previous research has almost exclusively focused on characterizing ripe ascocarps. We characterized the volatilome of the highly-prized black truffle (Tuber melanosporum) ascocarps from July, in an early development stage, to March, in the late harvesting season, and investigated the relationships among aroma, ascocarp growth and morphogenetic development. The aroma profile was analyzed using a head space gas chromatography technique coupled with mass spectrometer. Seventy-one volatile compounds were identified and three development stages were clearly distinguished according to the volatile profile. In unripe ascocarps of July-September, the profile was dominated by methanethiol (19 %), 4-penten-2-ol (11 %) and acetone (11 %), the monthly mean weight of ascocarps ranged 2-20 g, and morphogenetic stages 4-6a were prevalent. In unripe ascocarps of October-December, the most abundant volatiles were 4-penten-2-ol (21 %), methanethiol (20 %) and ethanol (13 %), the monthly mean ascocarp weight ranged 28-43 g, and morphogenetic stages 6a, 6b-c were prevalent. In ripe ascocarps (December-March), the most abundant volatiles were 4-penten-2-ol (17 %), dimethyl sulfide (16 %) and ethanol (10 %), ascocarp weight did not increase significantly, and 6b-c was practically the sole morphogenetic stage. Thirty volatiles were associated to one of these three development stages. Amongst those with higher occurrence, 4-penten-2-ol, dimethyl sulfide, ethyl acetate, 2-pentanol and 2-butanone were associated to ripe truffles, whereas methanethiol, isobutyl isobutyrate, butanedione and 3-methylanisole were associated to unripe truffles.
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Ascomicetos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Carpóforos/crescimento & desenvolvimento , Carpóforos/química , Estações do AnoRESUMO
To explore advanced oxidation catalysts, peroxymonosulfate (PMS) activation by Co-Ni-Mo/carbon nanotube (CNT) composite catalysts was investigated. A compound of NiCo2S4, MoS2, and CNTs was successfully prepared using a simple one-pot hydrothermal method. The results revealed that the activation of PMS by Co-Ni-Mo/CNT yielded an exceptional Rhodamine B decolorization efficiency of 99% within 20 min for the Rhodamine B solution. The degradation rate of Co-Ni-Mo/CNT was 4.5 times higher than that of Ni-Mo/CNT or Co-Mo/CNT, and 1.9 times as much than that of Co-Ni/CNT. Additionally, radical quenching experiments revealed that the principal active groups were 1O2, surface-bound SO4â¢-, and â¢OH radicals. Furthermore, the catalyst exhibited low metal ion leaching and favorable stability. Mechanism studies revealed that Mo4+ on the surface of MoS2 participated in the oxidation of PMS and the transformation of Co3+/Co2+ and Ni3+/Ni2+. The synergism between MoS2 and NiCo2S4 reduces the charge transfer resistance between the catalyst and solution interface, thus accelerating the reaction rate. Interconnected structures composed of metal sulfides and CNTs can also enhance the electron transfer process and afford sufficient active reaction sites. Our work provides a further understanding of the design of multi-metal sulfides for wastewater treatment.
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Supercapacitors (SCs) are widely recognized as competitive power sources for energy storage. The hierarchical structure of nickel vanadium sulfide nanoparticles encapsulated on graphene nanosheets (NVS/G) was fabricated using a cost-effective and scalable solvothermal process. The reaction contents of the composites were explored and optimized. TEM images displayed the nickel vanadium sulfide nanoparticles (NVS NPs) with 20-30 nm average size anchored to graphene nanosheets. The interconnection of graphene nanosheets encapsulating NVS nanoparticles effectively reduces the ion diffusion path between the electrode and electrolyte, thereby enhancing electrochemical performance. The NVS/G composite demonstrated improved electrochemical performance, achieving a maximum of 1437 F g-1 specific capacitance at 1 A g-1, remarkable rate capability retaining of 1050 F g-1 at 20 A g-1, and exceptional cycle stability with 91.2% capacitance retention following 10,000 cycles. The NVS/G composite was employed as a cathode, and reduced graphene oxide (rGO) was used as an anode material to assemble a device. Importantly, asymmetric SCs using NVS/G//rGO achieved 74.7 W h kg-1 energy density at 0.8 kW kg-1 power density, along with outstanding stability with 88.2% capacitance retention following 10,000 cycles. These superior properties of the NVS/G electrode highlight its significant potential in energy storage applications.