Showing papers on "Ammonium tetrathiomolybdate published in 2018"
TL;DR: In this paper, an unsupported molybdenum disulfide catalysts were synthesized from ammonium tetrathiomolybdate with chitosan, hexadecylammonium and Triton X100 as structural agents.
Abstract: Unsupported molybdenum disulfide catalysts were synthesized from ammonium tetrathiomolybdate with chitosan, hexadecylammonium and Triton X100 as structural agents by leaching of MoS2/Al2O3 and MoS2/C/Al2O3 catalyst supports with HF acid and covering of “FeS” seeds by the MoS2 shell. Activation of the solids was performed under the H2S/H2 flow or by the decomposition of precursors in the presence of a hydrocarbon solvent in an autoclave reactor with varied H2 pressure. X-ray diffraction, N2 adsorption, temperature-programmed reduction, X-ray photoelectron spectroscopy and transmission electron microscopy techniques were used to characterize their structure and morphology. The nature of organic additives and activation conditions affect the surface area, pore size distribution, and morphological characteristics of MoS2 particles. Hydrodesulfurization of dibenzothiophene was performed in an autoclave reactor over unsupported MoS2based catalysts. The catalytic behavior of bulk MoS2 catalysts showed that the hydrogenation pathway prevailed over the direct desulfurization pathway. Higher HYD/DDS selectivity for dibenzothiophene hydrogenation was observed with the bulk molybdenum disulfide catalyst formed by etching of the MoS2/Al2O3 catalyst support. Unsupported Mo sulfide catalysts exhibited high hydrogenation activity in dibenzothiophene hydrodesulfurization and, therefore, might find wide applications in hydroprocessing of heavy feed and co-hydrotreating of petroleum fractions and plant oils.
56 citations
TL;DR: An improved ex situ presulfidation method for the preparation of the CoMoS/γ-Al2O3 catalyst was developed with ammonium sulfide as the sulfiding agent, and the prepared catalysts were evaluated in selective hydrodesulfurization of fluid catalytic cracking (FCC) gasoline.
Abstract: An improved ex situ presulfidation method for the preparation of the CoMoS/γ-Al2O3 catalyst was developed with ammonium sulfide as the sulfiding agent, and the prepared catalysts were evaluated in selective hydrodesulfurization (HDS) of fluid catalytic cracking (FCC) gasoline. The selectivity of the ex situ presulfided catalysts was more than 4 times of that of the in situ presulfided catalysts. The characterization by XRD, HRTEM, XPS, TPR, and FT-IR indicated that ammonium sulfide effectively reacted with the supported Mo oxide to form ammonium tetrathiomolybdate as intermediate, thus realizing the more complete sulfidation of Mo oxide. However, the supported Co oxide could not be sulfided by ammonium sulfide, and the delayed sulfidation would not hinder the easy growth of MoS2 particles, subsequently lead to the significantly longer slab lengths of MoS2 particles than that of the in situ presulfided catalyst, which effectively decreased the number of active sites for olefins, thus inducing much higher H...
14 citations
TL;DR: It is demonstrated that TM blocks the proliferation of HNSCC cells, inhibits LOX activation and decreases the expression of the receptor activator of nuclear factor-κB ligand in osteoblasts and osteocytes, subsequently suppressing bone destruction, suggesting that copper is a potential target for the treatment of H NSCCs associated with bone destruction.
Abstract: Head and neck squamous cell carcinoma (HNSCC) poses a significant challenge clinically where one of the mechanisms responsible for the invasion into facial bones occurs via the activation of osteoclasts. Copper has been demonstrated to play a key role in skeletal remodeling. However, the role of copper in cancer-associated bone destruction is thus far unknown. Lysyl oxidase (LOX) is a copper-dependent enzyme that promotes osteoclastogenesis. In the present study, we investigated the effects of copper on HNSCC with bone invasion by the copper chelator, ammonium tetrathiomolybdate (TM) in vitro and in vivo. We demonstrate that TM blocks the proliferation of HNSCC cells, inhibits LOX activation and decreases the expression of the receptor activator of nuclear factor-κB ligand (RANKL) in osteoblasts and osteocytes, subsequently suppressing bone destruction. These findings suggest that copper is a potential target for the treatment of HNSCCs associated with bone destruction.
14 citations
TL;DR: In this paper, an unsupported MoS2 catalysts were prepared for the methanation reaction by varying the pressure and temperature in the hydrothermal reaction by using ammonium tetrathiomolybdate (ATTM).
Abstract: Unsupported MoS2 catalysts were prepared for the methanation reaction by varying the pressure and temperature in the hydrothermal reaction by using ammonium tetrathiomolybdate (ATTM). The physical and chemical characteristics of the catalysts were analyzed by using XRD, SEM, TEM, BET, XPS, H2-TPR, and CO-TPD techniques. The catalyst particles were formed in the bent fringe shape by stacking the (0 0 2) planes, and consisted mostly of MoS2, with some Mo2S5 and MoS3. It was found that the BET surface and active sites such as surface Mo4+ and sulfur vacancies increased with increasing preparation pressure, which could contribute to the improvement of MoS2 catalytic activity. The increase in preparation temperature not only favored the decomposition of ATTM into MoS2, but also lowered the number of active sites accessible for the reaction. Thus, it was suggested that the preparation temperature should be controlled at 350 °C to improve the catalytic activity.
14 citations
TL;DR: The Mo-S based inorganic salt ATM and cysteine containing peptides can form self-assembled adlayers on Au surfaces and these modified electrode materials exhibit miscellaneous catalytic activities as discussed by the authors.
Abstract: The Mo–S based inorganic salt ATM (ammonium tetrathiomolybdate) and cysteine containing peptides can form self-assembled adlayers on Au surfaces and these modified electrode materials exhibit miscellaneous catalytic activities. The ATM modified Au electrode catalyses the evolution of H2 from water even in the presence of O2 and other inhibitors. Moreover, water insoluble iron–porphyrins get immobilised on this construct through physiadsorption and thus it becomes a favourable ORR (O2 reduction reaction) catalyst. A naturally occurring peptide Ay(1–19), containing native cysteine residues, spontaneously forms an ordered SAM (self-assembled monolayer) on Au and upon heme binding this construct can catalyse the ORR with a higher catalytic rate compared to synthetic metallo-porphyrin based ORR catalysts. Human Aβ(1–16), appended with a cysteine residue at its C-terminus, gets readily immobilised on Au surfaces by SAM formation. These AβCys constructs represent different isoforms of Aβ in the absence and in the presence of various coadsorbant thiols. Upon individual as well as simultaneous binding of heme and Cu, these structurally different AβCys constructs exhibit diverse trends in generating oxidative stress, in vitro.
12 citations
TL;DR: In this paper, the essential role of Co on the MoS2 catalyst in selective hydrodesulfurization (HDS) of FCC gasoline was investigated with ammonium tetrathiomolybdate supported on alumina modified with various amount of Co sulfide.
11 citations
TL;DR: It is found that ammonium tetrathiomolybdate can inhibit the reaction of cisplatin with Cu-Atox1 and prevent the protein unfolding and aggregation induced by cis platin.
Abstract: Cisplatin is a widely used anticancer drug in clinic, and ammonium tetrathiomolybdate ([(NH4)2MoS4], TM) is a copper chelator used in clinic for the treatment of Wilson's disease. Recently, TM has been found to enhance the therapeutic effect of cisplatin; however, the origin of this effect is not clear. Here we found that TM can inhibit the reaction of cisplatin with Cu–Atox1 and prevent the protein unfolding and aggregation induced by cisplatin. Although Ag(I) binds to Atox1 in a way similar to Cu(I)–Atox1, TM does not prevent the reaction of Ag–Atox1 with cisplatin. This result indicates that the formation of a Mo-centered trimeric protein cluster in the TM–Cu–Atox1 system plays a role in the inhibitory effect. This work provides new insights into the mechanism by which TM enhances the cytotoxic efficacy of cisplatin and helps to circumvent cisplatin resistance of tumor cells.
10 citations
Patent•
09 Feb 2018
Abstract: The invention belongs to the technical field of electrocatalytic hydrogen evolution, and relates to a preparation method and application of a molybdenum disulfide/reduced graphene oxide-nitrogen carbide (MoS2/rGO-CN) composite material. The preparation method comprises the steps of: firstly adding graphite oxide into deionized water, adding melamine into the obtained mixture, then performing ultrasound dissolution so as to form a colloidal solution, adopting a hydrothermal method to prepare aerogel of reduced graphene oxide-nitrogen carbide, and then performing a solvothermal reaction to obtain the target product by adopting ammonium tetrathiomolybdate as a molybdenum source and a sulfur source and N,N-dimethylformamide as a solvent. The preparation method of the aerogel of the reduced graphene oxide-nitrogen carbide is simple and high in yield, and since the MoS2/rGO-CN is prepared by using the one-step solvothermal method, the preparation method has low cost and high repeatability and facilitates large-scale synthesis; by means of the prepared MoS2/rGO-CN composite material, the accumulation of the molybdenum disulfide is reduced, and the quantity of active sites is increased; the conductivity and the active area of the MoS2 can be improved through the combination of the MoS2 with the rGO-CN, and when the prepared MoS2/rGO-CN composite material is applied to an electrocatalytic hydrogen evolution reaction, excellent catalytic performance can be exhibited, and when the current density is 10 mA.cm , the overpotential is 203 mV, and the Tafel slope is 48 mV.dec .
4 citations
Patent•
27 Apr 2018
TL;DR: The pyramidal molybdenum disulfide nanosheet has an uniform size, has higher density boundary, and has good conductive performance and catalysis performance as discussed by the authors.
Abstract: The invention relates to a pyramidal molybdenum disulfide nanosheet and a preparation method and an application thereof. The method comprises the following steps: S1) taking a slide glass as a substrate and placing the slide glass in hydrofluoric acid for immersion for 3-5 min, then performing cleaning and removing silicate on a surface to generate a product, drying the product for standby; S2) using a chemical vapor deposition method, taking sublimed sulfur and molybdenum trioxide, molybdenum chloride or ammonium tetrathiomolybdate as a sulfur source and a molybdenum source, and growing molybdenum disulfide on a substrate of a three-temperature zone tubular furnace. The pyramidal molybdenum disulfide nanosheet has an uniform size, has higher density boundary, and has good conductive performance and catalysis performance.
2 citations
Patent•
18 May 2018
TL;DR: In this article, a molybdenum sulfide-ferrite nano-enzyme was used to detect hydrogen peroxide in a high-pressure reaction kettle, and repeatedly cleaned the product; drying the product so as to obtain ferrite magnesium.
Abstract: The invention relates to a molybdenum sulfide-ferrite nano-enzyme as well as a preparation method and an application method thereof. The preparation method comprises the following steps: uniformly mixing ferric chloride hydrate, magnesium chloride hydrate and dodecyl amine with a proper amount of ethylene glycol; enabling the components to react in a high-pressure reaction kettle, and repeatedly cleaning the product; drying the product so as to obtain ferrite magnesium; dissolving ammonium tetrathiomolybdate into dimethyl formamide; slowly adding hydrazine hydrate, and uniformly mixing; putting a proper amount of the ferrite magnesium into the mixed liquid; enabling the components to react in the high-pressure reaction kettle, and repeatedly cleaning the product; drying the product so as to obtain molybdenum sulfide-ferrite magnesium; putting the molybdenum sulfide-ferrite magnesium into a proper amount of TMB (Tetramethylbenzidine) and hydrogen peroxide-sodium acetate buffer solutionsof different concentrations; culturing, and testing the concentration of hydrogen peroxide. Results show that when being adopted to detect hydrogen peroxide, the molybdenum sulfide-ferrite magnesiumnano-enzyme is convenient and rapid to operate, high in sensitivity and wide in detection concentration range.
2 citations
Patent•
31 Aug 2018
TL;DR: In this article, a fluorescent molybdenum disulfide quantum dot was used to detect ferric ions, adenosine triphosphate and ascorbic acid.
Abstract: The invention belongs to the technical field of nano materials, and particularly relates to a fluorescent molybdenum disulfide quantum dot and a preparation method and application thereof. The methodcomprises the steps that ammonium tetrathiomolybdate serves as a precursor small molecule, formaldehyde serves as a reducing agent, and a molybdenum disulfide quantum dot is synthesized in one step byadopting a hydrothermal method or a solvothermal method in the presence of sodium hydroxide; the diameter of the obtained molybdenum disulfide quantum dot is less than 5 nanometers, the fluorescenceexcitation wavelength of the molybdenum disulfide quantum dot is 360-486 nanometers, and the fluorescence emission wavelength of the molybdenum disulfide quantum dot is 456-560 nanometers. The fluorescent molybdenum disulfide quantum dot can be used to detect ferric ions, adenosine triphosphate and ascorbic acid and construct an IMPLICATION logic gate. The fluorescent molybdenum disulfide quantumdot has the advantages of simple synthesis condition, stable performance, low price and the like; when the fluorescent molybdenum disulfide quantum dot is used for detecting the iron ions, the adenosine triphosphate and the ascorbic acid, the detection process is simple, the selectivity is high, and the sensitivity is high; and the IMPLICATION logic gate developed by taking MoS2 QDs as a platformhas an application potential for multiple analyte detection.
Patent•
12 Oct 2018
TL;DR: In this article, a preparation method of a molybdenum disulfide-nitrogen sulfur doped graphite foil composite nano material is described, and the composite material is obtained through oxidation and hydrothermal processes.
Abstract: The invention discloses a preparation method of a molybdenum disulfide-nitrogen sulfur doped graphite foil composite nano material The method uses graphite foil, HNO3, H2SO4, ammonium tetrathiomolybdate, thiourea, oxalic acid and ultrapure water as raw materials; and the method is realized by the following steps: graphite oxide foil doped by nitrogen and sulfur atoms is prepared; a hydrothermal synthesis reaction is performed; and washing is performed, and drying is performed According to the method disclosed by the invention, the raw materials are simple and easy to obtain, the composite material is obtained through oxidation and hydrothermal processes, the whole experimental process is simple and easy to operate, large-scale production of the product is very easy to realize, and the product can be recovered by 100% during use; the obtained molybdenum disulfide-nitrogen sulfur doped oxidized graphite foil has excellent flexibility, molybdenum disulfide grows on graphite foil in an epitaxial growth manner, and the product has good uniformity and a very good catalytic effect on electrocatalytic hydrogen evolution; and in addition, the material is expected to have a good application in aspects such as flexible batteries and flexible sensors
Patent•
04 Sep 2018
TL;DR: In this article, a method for preparing a molybdenum-based composite catalyst and application thereof is presented, which comprises the following steps: S1, dipping, namely adding a catalyst carrier into an ammonium tetrathiomolybdate solution for dipping, and filtering to take filter residues; S2, drying, namely drying the filter residues obtained in the S1 so as to obtain a dried material; S3, grinding, namely grinding the dried material obtained in S2 into powder; S4, calcining, namely performing high-temperature calc
Abstract: The invention discloses a method for preparing a molybdenum-based composite catalyst and application thereof The method comprises the following steps: S1, dipping, namely adding a catalyst carrier into an ammonium tetrathiomolybdate solution for dipping, and filtering to take filter residues; S2, drying, namely drying the filter residues obtained in the S1 so as to obtain a dried material; S3, grinding, namely grinding the dried material obtained in the S2 into powder; S4, calcining, namely performing high-temperature calcination on the powder obtained in the S3, wherein the high-temperaturecalcination is performed according to the following steps: raising the temperature to 350-420 DEG C at a rate of 3-15 DEG C per minute, calcining for 20-240 minutes, introducing oxygen-containing gases into the calcining process, wherein the volume content of oxygen in the oxygen-containing gas is not higher than 1%, thereby obtaining the molybdenum-based catalyst According to the method disclosed by the invention, the MoO2 molybdenum-based composite catalyst containing MoS2 can be prepared, and the sulfur resistance and stability of the molybdenum-based catalyst are improved; the molybdenum-based catalyst has high-efficiency coal and biomass catalytic hydrogenation property, and high oil yield can be obtained; hydrogen does not need to be used in the preparation process, and the safety is high; the preparation temperature is relatively high, and the preparation time is short