A highly active catalyst of phosphomolybdic acid ~HPMo） was prepared and applied in the catalytic oxidative desulfurization （CODS） system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. ...A highly active catalyst of phosphomolybdic acid ~HPMo） was prepared and applied in the catalytic oxidative desulfurization （CODS） system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. The influences of rn（catalyst）/m（oil）, V（H202）fV（oil）, reaction temperature and reaction time on the fractional conversion of benzothiophene （BT） and dibenzothiophene （DBT） were investigated. GC-MS and micra-coulometric methods were employed to investigate the reaction. The catalyst has high desulfurization activity in the removal of BT and DBT under mild conditions. The recycling experiments indicated that DBT and BT removal could still reach 95.2% and 95.7% after 10 cycles.展开更多
TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic aci...TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism.展开更多
Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane prop...Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane properties and proton conductivity were investigated. The crosslinking reaction between the hydroxyl group of PVA and the aldehyde group of glutaraldehyde （GA） was characterized by IR spectroscopy. Proton conductivity of the membranes increases with an increase in concentration of the doped PMA and also with an increase in crosslinking density of the membranes. Proton conductivity results indicate that a significant amount of PMA was maintained in the membranes even after several hours of immersion in water. A maximum conductivity of 0.0101 S cm^-1 was obtained for the membrane with 33.3 wt% PMA and crosslinking density of 5.825 mol%. X-ray diffraction studies were carried out to investigate the influence of PMA doping and crosslinking density on the nature of the membranes. These properties make them very good candidates for polymer electrolyte membranes for direct methanol fuel cell application.展开更多
In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different comme...In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different commercial adsorbents were used to eliminate thiophene at ambient pressure and mild temperature, and the results showed that carbon powder had the best adsorption ability. In the extractive desulfurization process, the best desulfurization result was obtained when DMF is used. In the oxidative/adsorptive desulfurization procedure using synthesized potassium ferrate as the oxidant and phosphomolybdic acid solution as the catalyst, thiophene was oxidized and removed from hydrocarbons in combination with active carbon adsorption, and the residual sulfur content of simulated oil could be reduced to 15.3mg/L from the original level of 200mg/L, with the desulfurization rate reaching 92.3%.展开更多
A highly active sulfided NiPMo/MCM-41(NiPMo-S/M41)hydrodesulfurization(HDS)catalyst was successfully synthesized using Keggin-type phosphomolybdic acid as the phosphorus and molybdenum source and thioacetamide as the ...A highly active sulfided NiPMo/MCM-41(NiPMo-S/M41)hydrodesulfurization(HDS)catalyst was successfully synthesized using Keggin-type phosphomolybdic acid as the phosphorus and molybdenum source and thioacetamide as the sulfur source.The supported catalysts NiPMo/M41,Ni_(2)P-Mo/M41,and Ni_(2)P/M41 were also prepared to investigate the effects of Mo,S,and the Keggin structure on the HDS performance.The HDS activities of NiPMo/M41 and NiPMo-S/M41 toward dibenzothiophene were much higher than that of Ni_(2)P-Mo/M41,demonstrating that the active phases in the Keggin-structured catalysts were significantly superior to the Mo-modified Ni_(2)P phase.The HDS activities of the catalysts followed the order NiPMo-S/M41(96.7%)>NiPMo/M41(89.9%)>Ni_(2)P-Mo/M41(53.5%)>Ni_(2)P/M41(48.9%).For Ni_(2)P/M41,Ni_(2)P-Mo/M41,and NiPMo/M41,cyclohexylbenzene(CHB)was formed in low concentrations(<21.0%),indicating that direct desulfurization was the favored reaction route and that this did not change for Keggin-structured NiPMo/M41.By contrast,the CHB selectivity of NiPMo-S/M41 increased to 44.6%,much higher than that of NiPMo/M41(17.6%),demonstrating that sulfidation enhanced the hydrogenation ability,which was ascribed to a metal-acid synergistic effect.展开更多
The efficient catalytic conversion of hazardous gases(e.g.,N_(2)O and CO)into non-harmful by products is important due to the severe environmental and health burdens posed by these gases.Here,quantum chemical studies ...The efficient catalytic conversion of hazardous gases(e.g.,N_(2)O and CO)into non-harmful by products is important due to the severe environmental and health burdens posed by these gases.Here,quantum chemical studies have been carried out to investigate the catalytic reduction of N_(2)O by CO over a phosphomolybdic acid(PMA)cluster anchored with 3d transition metal atoms under mild reaction conditions.For N_(2)O reduction,all 3d-TM_(1) adatoms on the PMA cluster have been systematically screened as single-atom catalysts(SACs).TM_(1)/PMA systems possess significant adsorption energies towards N_(2)O and CO,and co-adsorption energies of N_(2)O+CO are a necessary prerequisite for the start of the catalytic cycle.The results indicate that N_(2)O is decomposed first on the TM_(1)/PMA surface,forming N_(2)and O-TM_(1)/PMA intermediate.The Ti1-(0.53 eV),V_(1)-(0.40 eV),Cr1-(0.86 eV),and Fe_(1)/PMA(0.94 eV)have low activation energy barriers that are comparable to those of the other catalysts that were chosen,making them active and selective catalysts for the N_(2)O decomposition.However,the remaining O atom on the TM_(1)/PMA was an active species for the oxidation of CO molecules.The Fe_(1)/PMA catalyst has an activation energy barrier of 0.43 eV and is a promising catalyst for the oxidation of CO.CO occupying the TM_(1) site with stronger adsorption energy than N_(2)O will restrict the reaction’s effectiveness.A lower temperature can hinder the generation of the side products N_(2)and O_(2) generated due to the disproportionation of N_(2)O molecules.A concerted reaction mechanism can also initiate the reaction by first adhering CO molecules to the TM_(1)/PMA surface.The computed activation energy barriers of the rate-limiting step are(Ti_(1)=0.52 eV,V_(1)=0.76 eV,and Fe_(1)=0.88 eV),respectively.Thus,3d TM_(1)/PMA is predicted to be an efficient catalyst for converting toxic gases N_(2)O and CO into non-hazardous N_(2)and CO_(2) under normal conditions.展开更多
Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure an...Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure and harsh conditions to trade off lignin’s structural complexity and limited solubility.Herein,we developed an oxidation system for lignin depolymerization using a single phosphomolybdic acid(H_(3)PMo_(12)O_(40))catalyst in acetic acid solvent to address the aforementioned issues.The entire catalytic system was operated under only 0.1 MPa O_(2) pressure,providing over 20 wt% of aromatic compounds containing aldehydes and carboxylic acids.Theoretical calculations combined with experimental analyses reveal structural transformations and redox behavior driven by the synergistic interaction between H_(3)PMo_(12)O_(40) and acetic acid.Mechanistic studies detected superoxide radicals,confirming the joint role of catalyst and solvent in oxygen activation,radicals stabilization,and enhanced reaction efficiency.A low-cost,commercially available catalyst with minimal oxygen demand offers a promising route to industrial-scale biomass refining.展开更多
In the pH 7.4 Na2HPO4-NaH2PO4 buffer solution, the cationic surfactant （CS） interacted with nanogold particles （NG） to form NG aggregations （NGA） that resulted in its color changing from wine red to blue-violet....In the pH 7.4 Na2HPO4-NaH2PO4 buffer solution, the cationic surfactant （CS） interacted with nanogold particles （NG） to form NG aggregations （NGA） that resulted in its color changing from wine red to blue-violet. NG has a strong catalysis on the formic acid-phosphomolybdic acid （PMo） colored reaction, but that of the NGA catalysis is weak. With the increase of CS concentration, the NGA increased and the NG decreased, the catalysis decreased and the absorption value at 700 nm decreased linearly. The concentrations of 6.25-250 nmol/L tetradecyl dimethyl benzyl ammonium chloride （TDBAC）, 0.625-250 nmol/L cetyltrimethyl ammonium bromide （CTMAB） and 12.5 -500 nmol-L 1 dodecyldimethylbenzyl ammonium chloride （DDBAC） had good linear responses to the decreased absorption value （AA70o nm）, with molar absorption coefficients of 2.2 × 106, 2.1 × 106 and 9 ×105 Lomol 1.cm 1 respectively. This method was simple, highly sensitive and low-cost.展开更多
A simpe electrochemical sensor for detection of cholic acid （CA） was designed by modifying phosphomolybdate （PMol2） doped polypyrrole （PPy） film on glassy carbon electrode （PMo12-PPy/GCE）. The electrochemical ...A simpe electrochemical sensor for detection of cholic acid （CA） was designed by modifying phosphomolybdate （PMol2） doped polypyrrole （PPy） film on glassy carbon electrode （PMo12-PPy/GCE）. The electrochemical behavior of CA on PMo12-PPy/GCE was investigated by cyclic voltammetry and 0.5 order differential voltammetry. The results indicated that CA had high inhibitory activity toward the peak currents of PMo12-PPy/GCE. The reduction peak currents were linearly related to the logarithmic value of the concentration of CA from 1.0 × 10^- 7 to 1.0 × 10^-3 mol/L with a low detection limit of 1.0 × 10^- 8 mol/L. The developed sensor exhibited excellent sensitivity, selectivity and stability for detection of CA, and it could be successfully applied to detect the level of CA in the urine samples. Moreover, the response mechanism of CA on the PMo12-PPy/GCE was discussed in detail.展开更多
The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely ac...The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.展开更多
Hydroisomerization of n-heptane is an efficient method for producing gasoline with a high octane number.The focus of this study was to find a highly efficient catalyst that could both promote the conversion of n-hepta...Hydroisomerization of n-heptane is an efficient method for producing gasoline with a high octane number.The focus of this study was to find a highly efficient catalyst that could both promote the conversion of n-heptane and inhibit the cracking side reaction.MIL-101(Cr)is a chromium-based metal-organic framework(MOF)with good hydrothermal stability,and exhibits a three-dimensional pore structure that is similar to that of zeolites.Using phosphomolybdic acid(PMA;H3PMo12O40·xH2O)can increase the number of Brønsted acid sites on MIL-101(Cr),which contributes to improving the catalytic performance during isomerization.In this study,0.4%Pt/PMA-MIL-101(Cr)catalyst was successfully crystallized at 220℃using a hydrothermal synthetic method.The results showed that the synthesized samples were mesoporousmicroporous composite materials with the typical octahedral structure,and the MIL-101(Cr)framework was not damaged following modification with PMA.It was found that 0.4%Pt30%PMA-MIL-101(Cr)exhibited the best performance for isomerization of n-heptane,with a conversion rate and selectivity at 260°C of 47.6%and 96.6%,respectively.After five hours of reaction,the conversion rate and selectivity of the catalyst remained above 38%and 80%,respectively.展开更多
NH_(2)-MIL-125 is one of the most promising metal-organic frameworks(MOFs)for use as an adsorbent to remove nitrogen-containing compounds(NCCs)from fuels.In this study,NH_(2)-MIL-125 was further modified by loading th...NH_(2)-MIL-125 is one of the most promising metal-organic frameworks(MOFs)for use as an adsorbent to remove nitrogen-containing compounds(NCCs)from fuels.In this study,NH_(2)-MIL-125 was further modified by loading the highly electronegative F and the heteropoly acid phosphomolybdic acid hydrate(PMA).Hydrogen bonds are suggested to form between F and PMA.X-ray diffraction(XRD)and scanning electron microscopy(SEM)showed that the addition of these elements altered the morphology of NH_(2)-MIL-125,resulting in the growth of sectional octahedrons and cubes.The adsorptive denitrogenation(ADN)activity of 10%PMA@M125 was 1.7 times greater than that of NH_(2)-MIL-125 without F and PMA.The synergistic effect of F and PMA on the morphology and structure of NH_(2)-MIL-125 was examined,with a focus on different PMA contents.This study provides a simple method for modifying the morphology and structure of NH_(2)-MIL-125 by adding the required elements.展开更多
The conjugated organic molecules modified hourglass-shaped Co{P_(4)Mo_(6)}_(2)-phosphomolybdate hybrid with the formula of(H_(2)L1)_(2)(H_(2)L2)[Co(H_(2)O)_(4)]{Co[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(L1=2,2'...The conjugated organic molecules modified hourglass-shaped Co{P_(4)Mo_(6)}_(2)-phosphomolybdate hybrid with the formula of(H_(2)L1)_(2)(H_(2)L2)[Co(H_(2)O)_(4)]{Co[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(L1=2,2'-dimethyl-6,6'-biquinoline,L2=4,4'-diaminobiphenyl)was synthesized via the hydrothermal method and applied in the photocatalytic reduction of hexavalent chromium Cr(Ⅵ).Experimental results indicate that this hybrid is composed of 1D chains formed by Co{P_(4)Mo_(6)}_(2)phosphomolybdate anionics connected via single-bridged[Co(H_(2)O)_(4)]^(2+)cations,which further interact with conjugated organic molecules L1 and L2 via hydrogen bonds to form the 3D supramolecular structure.This hybrid exhibits an extensive absorption of visible light,coupled with an appropriate energy band structure,which contribute to its remarkable photocatalytic performance in the reduction of Cr(Ⅵ).Within 120 min,the reduction conversion of Cr(Ⅵ)can reach 86%.Moreover,this hybrid still shows excellent catalytic performance in actual aqueous samples,revealing its strong potential for practical applications.The mechanism of photocatalytic reduction reaction was further studied.This work provides a new method for designing efficient polyoxometalate-based photocatalysts for Cr(Ⅵ)reduction.展开更多
Heteropoly acid of Keggin structure phosphotungstic（HPW） and phosphomolybdic（HPMo） were chemically anchored to the modified SBA-15 channel. The materials were used as catalyst for oxidative desulfurization of orga...Heteropoly acid of Keggin structure phosphotungstic（HPW） and phosphomolybdic（HPMo） were chemically anchored to the modified SBA-15 channel. The materials were used as catalyst for oxidative desulfurization of organic sulfur compounds including benzothiophene （BT）, dibenzothiophene （DBT） and 4,6-dimethydibenzothiophene （4,6-DMDBT）. The experimental results show that the catalysts are efficient and reusable, the catalytic activity is hardly reduced even in the 5th cycle of use.展开更多
A novel mesoporous HPMo/SiO2 composite was synthesized by the sol-gel method with triblock copolymer EO20PO70EO20 as template.The properties of the product were characterized by X-ray diffraction,transmission electron...A novel mesoporous HPMo/SiO2 composite was synthesized by the sol-gel method with triblock copolymer EO20PO70EO20 as template.The properties of the product were characterized by X-ray diffraction,transmission electron microscopy,N2 adsorption-desorption isotherms,Fourier transform infrared spectrometer and inductively-coupled plasma analysis.The experimental results show that the product has a very ordered hexagonal mesostructure,and the HPMo is immobilized into the framework of silica.The final mesoporous composite shows excellent stability in polar solvents.Results of catalytic tests indicate that the composite is an effective catalyst for oxidation of dibenzothiophen,and there are few activity losses even after the third cycle of uses.The high catalytic activity and good insolubility make it a promising catalyst in oxidative desulfurization process.展开更多
Ammonium salts, （NH4）6HPMo11MO40 （M = Ni, Co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed...Ammonium salts, （NH4）6HPMo11MO40 （M = Ni, Co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9 ℃/min. They were characterized by BET method, XRD, 31p NMR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 ℃/min.展开更多
Mixed ammonium-transition metal salts with formula of （NH4）xMyHzPMo12O40 （M = Ni^2＋, Co^2＋ or Fe ^3＋） denoted as MPMo12 have been investigated for the oxidation of propane, with molecular oxygen, at temperature...Mixed ammonium-transition metal salts with formula of （NH4）xMyHzPMo12O40 （M = Ni^2＋, Co^2＋ or Fe ^3＋） denoted as MPMo12 have been investigated for the oxidation of propane, with molecular oxygen, at temperature range between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9℃/min. They were characterized by BET method, XRD, UV-Vis and IR techniques. The catalysts were found to be active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9℃/min. FePMo12 was found to be a more active catalyst for propene （17.2% yield） with minimal over deep oxidation （0.3% yield in COx）.展开更多
Abstra ct Utilizing efficient and durable photocatalysts for the removal of carcinogen Cr(Ⅵ)in wide pH water environment is of great significance for environment remediation.Herein,three conjugated organic component-...Abstra ct Utilizing efficient and durable photocatalysts for the removal of carcinogen Cr(Ⅵ)in wide pH water environment is of great significance for environment remediation.Herein,three conjugated organic component-functionalized hourglass-type phosphomolybdate hybrids with the formulas(H_(2)DBQ)[Fe(-H_(2)O)_(3)]_(2){Fe[P_(4)Mo_(6)0_(31)H_(7)]_(2)}·7H_(2)O(1),(H_(2)DBQ)_(2)(H_(2)DBP)[Fe(H_(2)O)_(4)]{Fe[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(2),(H_(2)DBP)_(2){Fe[P_(4-)Mo_(6)O_(31)H_(9)]_(2)}·10H_(2)O(3)(DBQ=2,2'-dimehyl-6,6'-biquinoline;DBP=4,4'-diaminobiphenyl)were synthesized via hydrothermal method as photocatalysts for reducing Cr(Ⅵ)under visible light illumination.Structure analysis showed that hybrids 1-3 consist of hourglass-type[Fe(P_(4)Mo_(6)O_(31)H_(6))_(2)]^(10)-(abbr.Fe{P_(4)Mo_(6)}_(2))poly anionic clusters functionalized with different proportional of conjugated organic components(DBQ and DBP)effectively regulated their visible-light absorption capabilities and electron structures,which could be employed to reflect the structure-activity relationship of materials.When used as catalysts for reducing Cr(Ⅵ),hybrids 1-3 displayed distinct photocatalytic activities with Cr(Ⅵ)removal efficiencies of 91%,86%and 81%with only 10 W of white light being used as illumination,which are superior to that of pristine Fe{P_(4)Mo_(6)}_(2)salt(62%).Moreover,hybrid 1 also maintained high Cr(Ⅵ)removal efficiencies above~85%and high structural stabilities in solutions with wide pH ranges of2.5-10.0.Mechanism investigation showed that the higher organic component conjugation levels could promote the optic al absorption and facilitate the electron transfer between Fe{P_(4)Mo_(6)}_(2)and org anic components,thus resulting in effective Cr(Ⅵ)reduction photocatalytic efficacy.This work provides a viable way to design the photocatalysts based on polyoxometalates for removing wastewater pollutants.展开更多
Photo-assisted electrochemical technique provides a promising approach towards carcinogen chromium(Ⅵ)detection,which requires reasonable catalyst design.Herein,an unusual hexa-nuclear cadmium cluster functionalized r...Photo-assisted electrochemical technique provides a promising approach towards carcinogen chromium(Ⅵ)detection,which requires reasonable catalyst design.Herein,an unusual hexa-nuclear cadmium cluster functionalized reductive phosphomolybdate hybrid as photo-electrochemical sensor was designed and synthesized with formula of{[Cd(H_(2)O)_(2)]_(2)[Cd(btmbp)]_(2)}{Cd(P_(4)Mo_(6)O_(31)H_(7))_(2)}·20H_(2)O(1)(btmbp=4,4′-bis((^(1)H-1,2,4-triazol-1-yl)methyl)biphenyl),in which the photoactive hexa-nuclear{Cd_(6)}clusters cooperated with reductive phosphomolybdate[P_(4)Mo_(6)O_(31)]^(12)−endow the material with wide light absorption and remarkable redox activity,thus achieving efficient photo-assisted electrochemical Cr(Ⅵ)detection performance.Under visible-light assistance,the detection limit(LOD)and sensitivity of Cr(Ⅵ)is 4.17 nmol/L(0.225 ppb)and 226.32μA L/μmol,which is apparently superior to the performance without photo-assistance(6.25 nmol/L and 106.95μA L/μmol)and far satisfies the demands of world health organization(WHO)for potable water(50 ppb).Moreover,compound 1 showed prominent Cr(Ⅵ)detection performance in practical water samples together with remarkable anti-interference capacity and good electrochemical durability.This work provides an important guidance for designing efficient polyoxometalate-based crystalline sensors for Cr(Ⅵ)detection.展开更多
This article describes a fast and simple electrochemical assay for detecting cell concentration.After cell death,the membrane of cells will be broken,and DNA molecules contained in the cells will be released,but this ...This article describes a fast and simple electrochemical assay for detecting cell concentration.After cell death,the membrane of cells will be broken,and DNA molecules contained in the cells will be released,but this does not happen in living cells.Sodium molybdate can react with the phosphate backbone of the released DNA molecules to form phosphomolybdate precipitation and produces a corresponding redox current.The higher the concentration of DNA,the stronger the intensity of the current generated.Sodium molybdate solution and centrifuged cell supernatant were added onto the glassy carbon electrode to determine the cell concentration by measuring the current intensity.The cell viability,which means the ratio of living cells to the total cells,can also be determined by this method.This assay has the advantages of high sensitivity,low detection limit,and wide detection range.In addition,this method was successfully applied to the detection of cell concentration in human serum,which has potential clinical applications.展开更多
基金supported by the National Natural Science Foundation of China (21473126)~~
文摘A highly active catalyst of phosphomolybdic acid ~HPMo） was prepared and applied in the catalytic oxidative desulfurization （CODS） system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. The influences of rn（catalyst）/m（oil）, V（H202）fV（oil）, reaction temperature and reaction time on the fractional conversion of benzothiophene （BT） and dibenzothiophene （DBT） were investigated. GC-MS and micra-coulometric methods were employed to investigate the reaction. The catalyst has high desulfurization activity in the removal of BT and DBT under mild conditions. The recycling experiments indicated that DBT and BT removal could still reach 95.2% and 95.7% after 10 cycles.
基金supported by the National Natural Science Foundation of China (No.61774073)Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University (No. 2016-25)Science and Technology Development Program of Jilin province (No. 20170101086JC)
文摘TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism.
文摘Hybrid proton conducting membranes of poly（vinyl alcohol） （PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane properties and proton conductivity were investigated. The crosslinking reaction between the hydroxyl group of PVA and the aldehyde group of glutaraldehyde （GA） was characterized by IR spectroscopy. Proton conductivity of the membranes increases with an increase in concentration of the doped PMA and also with an increase in crosslinking density of the membranes. Proton conductivity results indicate that a significant amount of PMA was maintained in the membranes even after several hours of immersion in water. A maximum conductivity of 0.0101 S cm^-1 was obtained for the membrane with 33.3 wt% PMA and crosslinking density of 5.825 mol%. X-ray diffraction studies were carried out to investigate the influence of PMA doping and crosslinking density on the nature of the membranes. These properties make them very good candidates for polymer electrolyte membranes for direct methanol fuel cell application.
基金financially supported by the Science and Technology Program of the Department of Education,Heilongjiang Province(11531012)
文摘In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different commercial adsorbents were used to eliminate thiophene at ambient pressure and mild temperature, and the results showed that carbon powder had the best adsorption ability. In the extractive desulfurization process, the best desulfurization result was obtained when DMF is used. In the oxidative/adsorptive desulfurization procedure using synthesized potassium ferrate as the oxidant and phosphomolybdic acid solution as the catalyst, thiophene was oxidized and removed from hydrocarbons in combination with active carbon adsorption, and the residual sulfur content of simulated oil could be reduced to 15.3mg/L from the original level of 200mg/L, with the desulfurization rate reaching 92.3%.
基金National Natural Science Foundation of China(Grant No.52006225).
文摘A highly active sulfided NiPMo/MCM-41(NiPMo-S/M41)hydrodesulfurization(HDS)catalyst was successfully synthesized using Keggin-type phosphomolybdic acid as the phosphorus and molybdenum source and thioacetamide as the sulfur source.The supported catalysts NiPMo/M41,Ni_(2)P-Mo/M41,and Ni_(2)P/M41 were also prepared to investigate the effects of Mo,S,and the Keggin structure on the HDS performance.The HDS activities of NiPMo/M41 and NiPMo-S/M41 toward dibenzothiophene were much higher than that of Ni_(2)P-Mo/M41,demonstrating that the active phases in the Keggin-structured catalysts were significantly superior to the Mo-modified Ni_(2)P phase.The HDS activities of the catalysts followed the order NiPMo-S/M41(96.7%)>NiPMo/M41(89.9%)>Ni_(2)P-Mo/M41(53.5%)>Ni_(2)P/M41(48.9%).For Ni_(2)P/M41,Ni_(2)P-Mo/M41,and NiPMo/M41,cyclohexylbenzene(CHB)was formed in low concentrations(<21.0%),indicating that direct desulfurization was the favored reaction route and that this did not change for Keggin-structured NiPMo/M41.By contrast,the CHB selectivity of NiPMo-S/M41 increased to 44.6%,much higher than that of NiPMo/M41(17.6%),demonstrating that sulfidation enhanced the hydrogenation ability,which was ascribed to a metal-acid synergistic effect.
基金support for this work from the Center for Catalysis and Separations(CeCaS).
文摘The efficient catalytic conversion of hazardous gases(e.g.,N_(2)O and CO)into non-harmful by products is important due to the severe environmental and health burdens posed by these gases.Here,quantum chemical studies have been carried out to investigate the catalytic reduction of N_(2)O by CO over a phosphomolybdic acid(PMA)cluster anchored with 3d transition metal atoms under mild reaction conditions.For N_(2)O reduction,all 3d-TM_(1) adatoms on the PMA cluster have been systematically screened as single-atom catalysts(SACs).TM_(1)/PMA systems possess significant adsorption energies towards N_(2)O and CO,and co-adsorption energies of N_(2)O+CO are a necessary prerequisite for the start of the catalytic cycle.The results indicate that N_(2)O is decomposed first on the TM_(1)/PMA surface,forming N_(2)and O-TM_(1)/PMA intermediate.The Ti1-(0.53 eV),V_(1)-(0.40 eV),Cr1-(0.86 eV),and Fe_(1)/PMA(0.94 eV)have low activation energy barriers that are comparable to those of the other catalysts that were chosen,making them active and selective catalysts for the N_(2)O decomposition.However,the remaining O atom on the TM_(1)/PMA was an active species for the oxidation of CO molecules.The Fe_(1)/PMA catalyst has an activation energy barrier of 0.43 eV and is a promising catalyst for the oxidation of CO.CO occupying the TM_(1) site with stronger adsorption energy than N_(2)O will restrict the reaction’s effectiveness.A lower temperature can hinder the generation of the side products N_(2)and O_(2) generated due to the disproportionation of N_(2)O molecules.A concerted reaction mechanism can also initiate the reaction by first adhering CO molecules to the TM_(1)/PMA surface.The computed activation energy barriers of the rate-limiting step are(Ti_(1)=0.52 eV,V_(1)=0.76 eV,and Fe_(1)=0.88 eV),respectively.Thus,3d TM_(1)/PMA is predicted to be an efficient catalyst for converting toxic gases N_(2)O and CO into non-hazardous N_(2)and CO_(2) under normal conditions.
文摘Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure and harsh conditions to trade off lignin’s structural complexity and limited solubility.Herein,we developed an oxidation system for lignin depolymerization using a single phosphomolybdic acid(H_(3)PMo_(12)O_(40))catalyst in acetic acid solvent to address the aforementioned issues.The entire catalytic system was operated under only 0.1 MPa O_(2) pressure,providing over 20 wt% of aromatic compounds containing aldehydes and carboxylic acids.Theoretical calculations combined with experimental analyses reveal structural transformations and redox behavior driven by the synergistic interaction between H_(3)PMo_(12)O_(40) and acetic acid.Mechanistic studies detected superoxide radicals,confirming the joint role of catalyst and solvent in oxygen activation,radicals stabilization,and enhanced reaction efficiency.A low-cost,commercially available catalyst with minimal oxygen demand offers a promising route to industrial-scale biomass refining.
基金This work was supported by the National Natural Science Foundation of China （Nos. 21075023, 20965002, 20865002）, the Natural Science Foundation of Guangxi （No. 099102 l z） and the Research Funds of Guangxi Water Conservancy.
文摘In the pH 7.4 Na2HPO4-NaH2PO4 buffer solution, the cationic surfactant （CS） interacted with nanogold particles （NG） to form NG aggregations （NGA） that resulted in its color changing from wine red to blue-violet. NG has a strong catalysis on the formic acid-phosphomolybdic acid （PMo） colored reaction, but that of the NGA catalysis is weak. With the increase of CS concentration, the NGA increased and the NG decreased, the catalysis decreased and the absorption value at 700 nm decreased linearly. The concentrations of 6.25-250 nmol/L tetradecyl dimethyl benzyl ammonium chloride （TDBAC）, 0.625-250 nmol/L cetyltrimethyl ammonium bromide （CTMAB） and 12.5 -500 nmol-L 1 dodecyldimethylbenzyl ammonium chloride （DDBAC） had good linear responses to the decreased absorption value （AA70o nm）, with molar absorption coefficients of 2.2 × 106, 2.1 × 106 and 9 ×105 Lomol 1.cm 1 respectively. This method was simple, highly sensitive and low-cost.
基金This work was supported by the Natural Science Foundation of Shanxi Province, China （No. 201601D202008） and the Joint Funds of the National Natural Science Foundation of China （No. U 1510103）.
文摘A simpe electrochemical sensor for detection of cholic acid （CA） was designed by modifying phosphomolybdate （PMol2） doped polypyrrole （PPy） film on glassy carbon electrode （PMo12-PPy/GCE）. The electrochemical behavior of CA on PMo12-PPy/GCE was investigated by cyclic voltammetry and 0.5 order differential voltammetry. The results indicated that CA had high inhibitory activity toward the peak currents of PMo12-PPy/GCE. The reduction peak currents were linearly related to the logarithmic value of the concentration of CA from 1.0 × 10^- 7 to 1.0 × 10^-3 mol/L with a low detection limit of 1.0 × 10^- 8 mol/L. The developed sensor exhibited excellent sensitivity, selectivity and stability for detection of CA, and it could be successfully applied to detect the level of CA in the urine samples. Moreover, the response mechanism of CA on the PMo12-PPy/GCE was discussed in detail.
基金This work was supported by the National Key R&D Program of China(Nos.2022YFB3504100 and 2022YFB3504102)Natural National Science Foundation of China(No.22276133)+1 种基金Natural National Science Foundation of China(No.U20A20132)Natural National Science Foundation of China(No.52106180).
文摘The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.
基金National Natural Science Foundation of China(Grant No.22272129).
文摘Hydroisomerization of n-heptane is an efficient method for producing gasoline with a high octane number.The focus of this study was to find a highly efficient catalyst that could both promote the conversion of n-heptane and inhibit the cracking side reaction.MIL-101(Cr)is a chromium-based metal-organic framework(MOF)with good hydrothermal stability,and exhibits a three-dimensional pore structure that is similar to that of zeolites.Using phosphomolybdic acid(PMA;H3PMo12O40·xH2O)can increase the number of Brønsted acid sites on MIL-101(Cr),which contributes to improving the catalytic performance during isomerization.In this study,0.4%Pt/PMA-MIL-101(Cr)catalyst was successfully crystallized at 220℃using a hydrothermal synthetic method.The results showed that the synthesized samples were mesoporousmicroporous composite materials with the typical octahedral structure,and the MIL-101(Cr)framework was not damaged following modification with PMA.It was found that 0.4%Pt30%PMA-MIL-101(Cr)exhibited the best performance for isomerization of n-heptane,with a conversion rate and selectivity at 260°C of 47.6%and 96.6%,respectively.After five hours of reaction,the conversion rate and selectivity of the catalyst remained above 38%and 80%,respectively.
基金supported by the National Energy R&D Center of Petroleum Refining Technology(RIPP,SINOPEC)Tianjin Research Innovation Project for Postgraduate Students(2022SKYZ041).
文摘NH_(2)-MIL-125 is one of the most promising metal-organic frameworks(MOFs)for use as an adsorbent to remove nitrogen-containing compounds(NCCs)from fuels.In this study,NH_(2)-MIL-125 was further modified by loading the highly electronegative F and the heteropoly acid phosphomolybdic acid hydrate(PMA).Hydrogen bonds are suggested to form between F and PMA.X-ray diffraction(XRD)and scanning electron microscopy(SEM)showed that the addition of these elements altered the morphology of NH_(2)-MIL-125,resulting in the growth of sectional octahedrons and cubes.The adsorptive denitrogenation(ADN)activity of 10%PMA@M125 was 1.7 times greater than that of NH_(2)-MIL-125 without F and PMA.The synergistic effect of F and PMA on the morphology and structure of NH_(2)-MIL-125 was examined,with a focus on different PMA contents.This study provides a simple method for modifying the morphology and structure of NH_(2)-MIL-125 by adding the required elements.
基金supported by the National Natural Science Foundation of China(22471056,22301058,22371065,21901060,and 21871076)the Natural Science Foundation of Hebei Province(B2024205033,B2024205007,B2022205005,and B2020205008)+6 种基金the Science and Technology Project of Hebei Education Department(QN2023049)the China Postdoctoral Science Foundation funded project(2021TQ0095)the Project of Science and Technology Department of Hebei Province(22567622H)the Science Foundation of Hebei Normal University(L2023B51)the Graduate Innovation Ability Cultivation Funding Project of Hebei Province(CXZZBS2024093)College Student Science and Technology Innovation Project of Hebei Province(202410094022)the Chemistry Postdoctoral Research Station at Hebei Normal University
文摘The conjugated organic molecules modified hourglass-shaped Co{P_(4)Mo_(6)}_(2)-phosphomolybdate hybrid with the formula of(H_(2)L1)_(2)(H_(2)L2)[Co(H_(2)O)_(4)]{Co[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(L1=2,2'-dimethyl-6,6'-biquinoline,L2=4,4'-diaminobiphenyl)was synthesized via the hydrothermal method and applied in the photocatalytic reduction of hexavalent chromium Cr(Ⅵ).Experimental results indicate that this hybrid is composed of 1D chains formed by Co{P_(4)Mo_(6)}_(2)phosphomolybdate anionics connected via single-bridged[Co(H_(2)O)_(4)]^(2+)cations,which further interact with conjugated organic molecules L1 and L2 via hydrogen bonds to form the 3D supramolecular structure.This hybrid exhibits an extensive absorption of visible light,coupled with an appropriate energy band structure,which contribute to its remarkable photocatalytic performance in the reduction of Cr(Ⅵ).Within 120 min,the reduction conversion of Cr(Ⅵ)can reach 86%.Moreover,this hybrid still shows excellent catalytic performance in actual aqueous samples,revealing its strong potential for practical applications.The mechanism of photocatalytic reduction reaction was further studied.This work provides a new method for designing efficient polyoxometalate-based photocatalysts for Cr(Ⅵ)reduction.
基金the National Natural Science Foundation of China (No.50272048)
文摘Heteropoly acid of Keggin structure phosphotungstic（HPW） and phosphomolybdic（HPMo） were chemically anchored to the modified SBA-15 channel. The materials were used as catalyst for oxidative desulfurization of organic sulfur compounds including benzothiophene （BT）, dibenzothiophene （DBT） and 4,6-dimethydibenzothiophene （4,6-DMDBT）. The experimental results show that the catalysts are efficient and reusable, the catalytic activity is hardly reduced even in the 5th cycle of use.
基金Funded by the Hubei Provincial Department of Education Science and Technology Program for Outstanding Young Talents (Q20081209)
文摘A novel mesoporous HPMo/SiO2 composite was synthesized by the sol-gel method with triblock copolymer EO20PO70EO20 as template.The properties of the product were characterized by X-ray diffraction,transmission electron microscopy,N2 adsorption-desorption isotherms,Fourier transform infrared spectrometer and inductively-coupled plasma analysis.The experimental results show that the product has a very ordered hexagonal mesostructure,and the HPMo is immobilized into the framework of silica.The final mesoporous composite shows excellent stability in polar solvents.Results of catalytic tests indicate that the composite is an effective catalyst for oxidation of dibenzothiophen,and there are few activity losses even after the third cycle of uses.The high catalytic activity and good insolubility make it a promising catalyst in oxidative desulfurization process.
文摘Ammonium salts, （NH4）6HPMo11MO40 （M = Ni, Co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9 ℃/min. They were characterized by BET method, XRD, 31p NMR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 ℃/min.
文摘Mixed ammonium-transition metal salts with formula of （NH4）xMyHzPMo12O40 （M = Ni^2＋, Co^2＋ or Fe ^3＋） denoted as MPMo12 have been investigated for the oxidation of propane, with molecular oxygen, at temperature range between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9℃/min. They were characterized by BET method, XRD, UV-Vis and IR techniques. The catalysts were found to be active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9℃/min. FePMo12 was found to be a more active catalyst for propene （17.2% yield） with minimal over deep oxidation （0.3% yield in COx）.
基金financially supported by the National Natural Science Foundation of China(Nos.21871076 and21901060)the Natural Science Foundation of Hebei Province(Nos.B2022205005,B2020205008,B2019205074 and B2016205051)+3 种基金the Nature Science Foundation of Hebei Education Department(No.BJ2020037)the Innovation Capability Improvement Plan Project of Hebei Province(No.22567604H)China Postdoctoral Science Foundation funded project(No.2021TQ0095)the Science Foundation of Hebei Normal University(No.L2019B15)。
文摘Abstra ct Utilizing efficient and durable photocatalysts for the removal of carcinogen Cr(Ⅵ)in wide pH water environment is of great significance for environment remediation.Herein,three conjugated organic component-functionalized hourglass-type phosphomolybdate hybrids with the formulas(H_(2)DBQ)[Fe(-H_(2)O)_(3)]_(2){Fe[P_(4)Mo_(6)0_(31)H_(7)]_(2)}·7H_(2)O(1),(H_(2)DBQ)_(2)(H_(2)DBP)[Fe(H_(2)O)_(4)]{Fe[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(2),(H_(2)DBP)_(2){Fe[P_(4-)Mo_(6)O_(31)H_(9)]_(2)}·10H_(2)O(3)(DBQ=2,2'-dimehyl-6,6'-biquinoline;DBP=4,4'-diaminobiphenyl)were synthesized via hydrothermal method as photocatalysts for reducing Cr(Ⅵ)under visible light illumination.Structure analysis showed that hybrids 1-3 consist of hourglass-type[Fe(P_(4)Mo_(6)O_(31)H_(6))_(2)]^(10)-(abbr.Fe{P_(4)Mo_(6)}_(2))poly anionic clusters functionalized with different proportional of conjugated organic components(DBQ and DBP)effectively regulated their visible-light absorption capabilities and electron structures,which could be employed to reflect the structure-activity relationship of materials.When used as catalysts for reducing Cr(Ⅵ),hybrids 1-3 displayed distinct photocatalytic activities with Cr(Ⅵ)removal efficiencies of 91%,86%and 81%with only 10 W of white light being used as illumination,which are superior to that of pristine Fe{P_(4)Mo_(6)}_(2)salt(62%).Moreover,hybrid 1 also maintained high Cr(Ⅵ)removal efficiencies above~85%and high structural stabilities in solutions with wide pH ranges of2.5-10.0.Mechanism investigation showed that the higher organic component conjugation levels could promote the optic al absorption and facilitate the electron transfer between Fe{P_(4)Mo_(6)}_(2)and org anic components,thus resulting in effective Cr(Ⅵ)reduction photocatalytic efficacy.This work provides a viable way to design the photocatalysts based on polyoxometalates for removing wastewater pollutants.
基金supported by the National Natural Science Foundation of China(Nos.21871076.21901060)Natural Science Foundation of Hebei Province(Nos.B2016205051,B2020205008 and B2019205074)+2 种基金Science and Technology Project of Hebei Education Department(No.BJ2020037)Project funded by China Postdoctoral Science Foundation(No.2021TQ0095)the Science Foundation of Hebei Normal University(No.L2019B15).
文摘Photo-assisted electrochemical technique provides a promising approach towards carcinogen chromium(Ⅵ)detection,which requires reasonable catalyst design.Herein,an unusual hexa-nuclear cadmium cluster functionalized reductive phosphomolybdate hybrid as photo-electrochemical sensor was designed and synthesized with formula of{[Cd(H_(2)O)_(2)]_(2)[Cd(btmbp)]_(2)}{Cd(P_(4)Mo_(6)O_(31)H_(7))_(2)}·20H_(2)O(1)(btmbp=4,4′-bis((^(1)H-1,2,4-triazol-1-yl)methyl)biphenyl),in which the photoactive hexa-nuclear{Cd_(6)}clusters cooperated with reductive phosphomolybdate[P_(4)Mo_(6)O_(31)]^(12)−endow the material with wide light absorption and remarkable redox activity,thus achieving efficient photo-assisted electrochemical Cr(Ⅵ)detection performance.Under visible-light assistance,the detection limit(LOD)and sensitivity of Cr(Ⅵ)is 4.17 nmol/L(0.225 ppb)and 226.32μA L/μmol,which is apparently superior to the performance without photo-assistance(6.25 nmol/L and 106.95μA L/μmol)and far satisfies the demands of world health organization(WHO)for potable water(50 ppb).Moreover,compound 1 showed prominent Cr(Ⅵ)detection performance in practical water samples together with remarkable anti-interference capacity and good electrochemical durability.This work provides an important guidance for designing efficient polyoxometalate-based crystalline sensors for Cr(Ⅵ)detection.
基金supported by the National Natural Science Foundation of China(No.21575165)。
文摘This article describes a fast and simple electrochemical assay for detecting cell concentration.After cell death,the membrane of cells will be broken,and DNA molecules contained in the cells will be released,but this does not happen in living cells.Sodium molybdate can react with the phosphate backbone of the released DNA molecules to form phosphomolybdate precipitation and produces a corresponding redox current.The higher the concentration of DNA,the stronger the intensity of the current generated.Sodium molybdate solution and centrifuged cell supernatant were added onto the glassy carbon electrode to determine the cell concentration by measuring the current intensity.The cell viability,which means the ratio of living cells to the total cells,can also be determined by this method.This assay has the advantages of high sensitivity,low detection limit,and wide detection range.In addition,this method was successfully applied to the detection of cell concentration in human serum,which has potential clinical applications.
