Nuclear energy provides a competitive path for reduction of CO_(2)with water,whereas the high-efficiency utilization of radioly tic ally produced active species for oriented transformation remains challenging.Herein,w...Nuclear energy provides a competitive path for reduction of CO_(2)with water,whereas the high-efficiency utilization of radioly tic ally produced active species for oriented transformation remains challenging.Herein,we report the assembling of yttrium-decorated bimetallic MOFs via one-step hydrothermal strategy,which can act as a sensitized nanoreactor for syngas production under y-ray irradiation.The flower-shaped CuNi-MOF matrix with tunable metal centers exposed plentiful cooperative active sites for CO_(2)binding,and its nanopetals enabled the well dispersion of Y_(2)O_(3)nanoparticles on the surfaces.The introduction of high-Z element Y enhanced the secondary electron scattering and promoted the water radiolysis to produce more hydrated electrons(e_(aq)^(-)),thus accelerating the initial CO_(2)activation to CO_(2)^(·-).Moreover,the in situ formed coupling interlayer provided a fast charge transfer channel between Y_(2)O_(3)and the MOF framework,which facilitated the interfacial electron migration for intermediate generation and subsequent CO_(2)conversion.By regulating the contents of Cu and Y_(2)O_(3)within the nanocomposites,the affinity toward CO_(2)and the product compositions could be modulated.As a result,the optimal 7CN-2Y catalyst achieved a high syngas evolution rate of 311.07μmol g^(-1)with a H_(2)/CO ratio of 2.7:1 at an absorbed dose of 4 kGy.The present study offered a feasible route for the efficient transformation of CO_(2)into valuable chemicals and the design of viable catalysts for ionizing radiation.展开更多
The precipitation behavior,corrosion,and passivation performance of solutionized and severely sensitized SAF 2507 super-duplex stainless steel subjected to a temperature of 900℃for 10 h are investigated in a twofold ...The precipitation behavior,corrosion,and passivation performance of solutionized and severely sensitized SAF 2507 super-duplex stainless steel subjected to a temperature of 900℃for 10 h are investigated in a twofold concentrated seawater at 60℃.The sensitized alloy exhibits 66.1%γphases and 33.9%σphases,and the originalαphases have completely decomposed through eutectoid transformation,resulting in a microstructure characterized by coarse blockyσ/γ2 aggregates.High defect densities and an increased amount of oxyhydroxides and hydroxides are present in the passive film on the sensitized alloy,thereby enhancing n-type semiconducting character.The inferior performance of the passive film on the sensitized alloy is ascribed to the increased potential drop across the film/solution interface,the high defect densities,and the pronounced n-type character of the passive film resulting from the variations in its constituents.The precipitation ofσphase during sensitization significantly increases intergranular corrosion susceptibility and decreases critical pitting temperature,breakdown potential,and polarization resistance in hot concentrated seawater.展开更多
To achieve high power conversion efficiency(PCE),three porphyrin sensitizers have been synthesized and explored to simultaneously enhance the photocurrent(JSC)and photovoltage(VOC).On basis of the XW4,a benzothiadiazo...To achieve high power conversion efficiency(PCE),three porphyrin sensitizers have been synthesized and explored to simultaneously enhance the photocurrent(JSC)and photovoltage(VOC).On basis of the XW4,a benzothiadiazole(BTD)unit has been introduced to afford XW57 with the aim to extend the absorption wavelength and enhance the light harvesting ability.As a result,a JSC of 13.72 mA/cm^2 has been obtained for XW57,higher than that of XW4.On this basis,XW58 has been prepared by modifying the carbazole-based donor with two bulky dihexyloxyphenyl groups,and the superior anti-aggregation character raises the VOC from 781 mV(XW4)to 844 mV.When both the BTD unit and the bulky groups are introduced to the acceptor and donor units,respectively,the resulting sensitizer XW59 exhibits a highest PCE value of 7.34%with synergistically enhanced JSC of 13.19 mA/cm^2 and VOC of 793 mV.These results provide further insight into developing high performance dye-sensitized solar cells.展开更多
The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research stat...The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research status of sensitizer dyes based on metalloporphyrins applied in dye sensitized solar cells was summarized. The preparation and construction of sensitizer electrodes and dye sensitized solar cells based on metal organic frameworks (MOFs) of (metallo)porphyrin/phthalocyanine were projected.展开更多
Fresh leaves of oil bean (P. macrophylla) were used as sensitizers for fabrication of dye sensitized solar cells (DSSCs) at four dye pH values of 2.58°C at 23.7°C, 2.62°C at 22.2°C, 2.65°C at ...Fresh leaves of oil bean (P. macrophylla) were used as sensitizers for fabrication of dye sensitized solar cells (DSSCs) at four dye pH values of 2.58°C at 23.7°C, 2.62°C at 22.2°C, 2.65°C at 22.3°C and 3.61°C at 22.1 °C. The methanol extracts of P. macrophylla were extracted and used as sensitizers for the development of dye sensitized solar cells. The solar cells sensitized by P. macrophylla leaf extracts realised up to short circuit current (Jsc) 0.16 mA/cm2, open circuit voltage (Voc) 0.045 V, Pmax 0.031 mW/ cm2 and fill factor (FF) 0.50. The energy conversion efficiency (η) of the DSSCs is 0.43%. Phytochemical screening of P. macrophylla leaf extract shows the presence of flavonoids and anthraquinones. The nanostructured dye shows conversion of solar energy into electricity using low cost natural dyes as wide band-gap semiconductor sensitizers in DSSCs. This will provide economically viable substitute to silicon p-n junction photovoltaic (PV).展开更多
Dye-sensitized solar cells (DSSC) were fabricated with mango leaf dye extracts as natural dye sensitizers at pH value of 5.20 and temperature of 18.1°C. Methanol was used as dye-extracting solvent. DSSCs from dye...Dye-sensitized solar cells (DSSC) were fabricated with mango leaf dye extracts as natural dye sensitizers at pH value of 5.20 and temperature of 18.1°C. Methanol was used as dye-extracting solvent. DSSCs from dye extract of M. indica L. with KMnO4 electrolyte had the highest photocurrent density of 1.3 mA/cm2 and fill factor FF of 0.46 for the sun at its peak. Potassium permanganate (KMnO4) had a photocurrent density of 1.3 mA/cm2 and FF of 0.8 at sundown. Potassium Iodide (KI), Potassium Bromide (KBr) and Mercury Chloride (HgCl2) electrolytes had 0.2 mA/cm2, 0.08 mA/cm2 and 0.02 mA/cm2 photocurrent densities respectively. The fill factors of 0.09, 0.03 and 0.003 respectively for sun overhead while 0.08 mA/cm2, 0.01 mA/cm2 and 0.01 mA/cm2 were the values of photocurrent densities respectively at sundown. The fill factors were 0.02, 0.0006 and 0.003 respectively at sundown. The maximum power Pmax of the DSSCs were 0.5 mW/cm2, 0.10 mW/cm2, 0.01 mW/cm2 and 0.012 mW/cm2 respectively at 1300 h at 1630 h 0.9 mW/cm2, 0.14 mW/cm2, 0.005 mW/cm2 and 0.0015 mW/cm2 respectively.展开更多
Carbon dots(Cdots)with a broad light absorption range could be a potential stable sensitizer for TiO2,which is an excellent ultraviolet(UV)response photocatalyst.Herein,we systematically investigated the different col...Carbon dots(Cdots)with a broad light absorption range could be a potential stable sensitizer for TiO2,which is an excellent ultraviolet(UV)response photocatalyst.Herein,we systematically investigated the different color emissive Cdots-sensitized TiO2 for H2 production.Firstly,all kinds of Cdots enhanced the photocatalytic properties of TiO2.All the Cdots-sensitized TiO2 exhibits visible light H2 production due to their absorption in the visible light region.The photocurrent and H2 production amount display strong dependence on the light absorption range of Cdots.The blue-emissive Cdots endow the weak H2 production rate due to its weak absorption in the visible light.The enhanced photocatalytic activities are mainly contributed to the strong light absorbance and high-efficient charge separation.The light absorption of green-and red-emissive Cdots is another main factor for the high catalytic activities besides charge separation.展开更多
Non-alcoholic fatty liver disease(NAFLD) is the leading cause of liver disease in the Western world and is closely associated with metabolic syndrome,which includes hypertension,central obesity,dyslipidemia and insuli...Non-alcoholic fatty liver disease(NAFLD) is the leading cause of liver disease in the Western world and is closely associated with metabolic syndrome,which includes hypertension,central obesity,dyslipidemia and insulin resistance.NAFLD includes a wide spectrum of liver alterations,ranging from simple hepatic steatosis to variable degrees of fibrosis,cirrhosis and even hepatocellular carcinoma.Although the etiology and progression of the disorder remain poorly understood,insulin resistance is considered to play a pivotal role in the pathogenesis.Insulin sensitizers such as biguanides,thiazolidinediones(TZDs),glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase 4 inhibitors have been studied as therapeutic approaches for NAFLD in recent years.Metformin improves insulin sensitivity and serum alanine transaminase and aspartate transaminase(ALT/AST) levels in the majority of subjects; however,it has no significant effect on liver histology.TZDs improve insulin sensitivity,serum ALT/ AST levels and histology in some cases,but there are some concerns about the safety of long-term therapy.Selection of appropriate patients for avoiding side effects and the treatment of underlying disease are themain points.These drugs are the best choice for the treatment of NAFLD in patients with type 2 DM who are also candidates for treatment with an insulin sensitizer.The present review provides an overview of insulin sensitizers in the treatment of NAFLD.展开更多
BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller su...BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The photocatalytic activities of the catalysts were evaluated for the degradation of methyl orange (MO) solution under UV and visible light irradiation. The effects of catalyst amount, initial pH value, initial concentration of MO, as well as KI amount were investigated. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst was also tested. It is shown that BiOI sensitization enhances the photocatalytic activities of TiO2. With BiOI content increasing, the photocatalytic activities of BiOI/TiO2 under UV and visible light irradiation first increase, reaching a maximum around BiOI content of 1.7%, and then decrease with further increasing BiOI content. The 1.7% BiOI/TiO2 catalyst obviously exhibits much higher visible light photocatalytic activity than P25, and its UV light photocatalytic activity is slightly higher than that of P25. Under the conditions of a catalytic dose of 1.5 g.L-1, initial pH of 3.0, initial MO concentration of 20 mg.L-1, UV power of 300 W, and air flow rate of 0.8 L.min-1, complete degradatio is achieved within 60 min. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst is highly reliable.展开更多
Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadol...Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadolinium(Ⅲ) coordination complex,[Gd_(2)(DPDB)_6(DMF)_6(H_(2)O_()2)](DPDB=[(4-dimethylamino)phenyldiazenyl] benzenesulfonate),which was used as an inorganic sensitizer for boosting the visible light-harvesting and quantum efficiency of TiO_(2) supported-reduced graphene oxide(rGO) nanocomposite.Crystal structure of [Gd_(2)(DPDB)_6(DMF)_6(H_(2)O)_(2)](Gd-CMP) was determined from single-crystal X-ray diffraction data,which indicates three-dimensional(3D) supramolecular architecture through hydrogen bonding and CH…π_(ph) interactions.The prepared nanohybrid(Gd-CMP/TG) reveals significantly enhanced visible-light-induced photocatalytic activity for degradation of acetaminophen(ACT).The complete removal of 10 mg/L ACT is achieved over Gd-CMP/TG,and the corresponding rate constant of ACT degradation of nanohybrid is 40-fold higher than that of bare TiO_(2).In prepared ternary nanohybrid,metal-coordination sensitizer(Gd-CMP) acts as an electron donor,and at the same time,rGO serves as an electron acceptor,and the synergistic effect between them efficiently enhances charges separation and inhibits e/h pair recombination in the hybridized species.The radical scavenger tests indicate that the photo-induced O_(2)^(-·) radicals dominate ACT degradation.On the basis of the experimental results and calculated energy of electronic levels,a possible mechanism for the improved photocatalytic activity is discussed.展开更多
The past few years witnessed extensive emergence of short-wavelength upconversion(UC)emission stimulated photoactivation studies.However,low efficiency of multi-photon process greatly limits further applications.Here,...The past few years witnessed extensive emergence of short-wavelength upconversion(UC)emission stimulated photoactivation studies.However,low efficiency of multi-photon process greatly limits further applications.Here,ultraviolet(UV)upconversion emissions originated from multi-photon process of Tm^3+were studied with Nd^3+-sensitized NaGdF4:Yb,Tm@NaYF4:Nd,Yb core/shell nanoparticles.Crucial factors,including the contents of sensitizers Nd^3+,Yb^3+and activator Tm^3+,as well as the excitation power density were investigated based on the UV emission.Spectral results showed that high contents of Nd^3+in shell region up to 50%(molar fraction hereafter)and Yb^3+of 10%were essential to mediate the energy transfer via the core/shell interface and facilitate multi-photon UV emissions.Compared with segregated activator and sensitizer,a core/shell strategy with isolated Nd^3+in the shell was important for higher UV emission.Although the upconverting process was initiated with Nd^3+→Yb^3+,the short-wavelength emissions were intrinsically coming from four-and five-photon process.The optimized nanoparticles were found to be able to manipulate the configuration transition of azobenzene molecules,and it could be promising for near infrared(NIR)triggered optical switches applications.展开更多
Titania is one kind of important materials, which has been extensively investigated because of its unique electronic and optical properties. Research efforts have largely focused on the optimization of the dye,but rec...Titania is one kind of important materials, which has been extensively investigated because of its unique electronic and optical properties. Research efforts have largely focused on the optimization of the dye,but recently the titania nanostructures electrode itself has attracted more attention. It has been shown that particle size, shape, crystallinity, surface morphology, and chemistry of the TiO_2 material are key parameters which should be controlled for optimized performance of the solar cell. Titania can be found in different shape of nanostructures including mesoporous, nanotube, nanowire, and nanorod structures. The present article reviews the structural, synthesis, electronic, and optical properties of TiO_2 nanostructures for dye sensitized solar cells.展开更多
Upconversion phosphors are known as a material system that can convert near-infrared light into visible/ultraviolet emissions by sequentially absorbing multiple photons. The studies on upconversion materials often use...Upconversion phosphors are known as a material system that can convert near-infrared light into visible/ultraviolet emissions by sequentially absorbing multiple photons. The studies on upconversion materials often use two rare earth(RE) ions as a sensitizer-activator pair. We investigated the influences on luminescence intensity depending on Cr-doping content(x) of hexagonal NaLu_(0.98-x)Cr_xF4 Er_(0.02)(x = 0-0.9)upconversion material by substituting Lu^(3+) ions with Cr^(3+)in the absence of Gd^(3+). The change in upconversion luminescence intensity appears with saddle-like shape. We suggest that Cr^(3+) ions play the dual role as a constituent in host lattice and a sensitizer in the upconversion process. Optimal conditions for gaining the strongest upconversion emission correspond to x = 0.3-0.5, where there are effective energy transfers between Cr^(3+) and Er^(3+) ions and Cr-Er dimers. Apart from these values, the emission intensity decreases rapidly which can be ascribed to the absence of multiple-photon absorption for the case of low Cr^(3+) contents, and to the coupling between Cr^(3+) and/or Er^(3+) ions for the case of high Cr^(3+)contents. Magnetization and electron-spin-resonant measurements were performed to understand the correlation between the optical and magnetic properties.展开更多
AIM: We studied the effect of colchicine combined with radiation on the survival of human hepatocellular carcinoma (HCC) HA22T/VGH cells.METHODS: Twenty-four hours after treatment with 0-8 ng/mL colchicine, HA22T/...AIM: We studied the effect of colchicine combined with radiation on the survival of human hepatocellular carcinoma (HCC) HA22T/VGH cells.METHODS: Twenty-four hours after treatment with 0-8 ng/mL colchicine, HA22T/VGH cells were irradiated at various doses (0, 1, 2, 4, and 8 Gy). Colony assay was performed to assess the surviving cell fraction. Survival curves were fitted by using a linear-quadratic model to estimate the sensitizer enhancement ratio (SER). Flow cytometry was used for cell cycle analysis.RESULTS: Colchicine at lower concentrations (1 and 2 ng/mL) had obvious synergy with radiation to inhibit HCC cell growth, whereas higher concentrations (4 and 8 ng/mL) had only additive effect to radiation. Pretreatment with 1 and 2 ng/mL colchicine for 24-h enhanced cell killing by radiation with SERs of 1.21 and 1.53, respectively.G2/N arrest was only observed with higher colchicine doses (8 and 16 ng/mL) after 24-h treatment, this effect was neither seen with lower doses (1, 2, and 4 ng/mL)nor with any dose after only 1 h of treatment.CONCLUSION: Our results suggest that colchicine has potential as an adjunct to radiotherapy for HCC treatment.Lower doses of colchicine possess radiosensitizing effects via some mechanism other than G2/M arrest. Further study is necessary to elucidate the mechanism.展开更多
The pure TiO2 and Fe salts [Fe(C2O4)3,5H2O]-doped TiO2 electrodes were prepared by the hydrothermal method. The pure TiO2 or Fe-doped TiO2 slurry was coated onto the fluorine-doped tin oxide glass substrate by the D...The pure TiO2 and Fe salts [Fe(C2O4)3,5H2O]-doped TiO2 electrodes were prepared by the hydrothermal method. The pure TiO2 or Fe-doped TiO2 slurry was coated onto the fluorine-doped tin oxide glass substrate by the Doctor Blade method and then sintered at 450 ℃. The Mott-Schottks, plot indicates that the fiat band potential of TiO2 was shifted positively after Fe-doped TiO2. The positive shift of the fiat band potential improves the driving force of injected electrons from the LUMO of the dye to the conduction band of TiO2. This study shows that photovoltaic efficiency increased by 22.9% from 6.07% to 7.46% compared to pure TiO2, and the fill factors increased from 0.53 to 0.63.展开更多
The role of oxygen and the generation of active radicals in the photocatalitic degradation of phenol were investigated using the eosin sensitized TiO2 as photocatalyst under visible light irradiation. Diffuse reflecta...The role of oxygen and the generation of active radicals in the photocatalitic degradation of phenol were investigated using the eosin sensitized TiO2 as photocatalyst under visible light irradiation. Diffuse reflectance spectra show that the absorbancy range of eosin/TiO2 is expanded from 378 nm (TiO2 ) to about 600 nm. The photocatalitic degradation of phenol is almost stopped when the eosin/TiO2 system is saturated with N2 , which indicates the significance of O2 . The addition of NaN 3 (a quencher of single oxygen) causes about a 62% decrease in the phenol degradation. The phenol degradation ratio is dropped from 92% to 75% when the isopropanol (a quencher of hydroxyl radical) is present in the system. The experimental results show that there are singlet oxygen and hydroxyl radical generated in the eosin/TiO2 system under visible light irradiation. The changes of absorbancy indicate that the hydrogen peroxide might be produced. Through the analysis and comparison, it is found that the singlet oxygen is the predominant active radical for the degradation of phenol.展开更多
To develop efficient concerted companion(CC)dyes for fabricating high-performance DSSCs,three organic dyes XL1-XL3 have been designed by varying the position and number of theβ-hexylthiophene(HT)bridges,and these org...To develop efficient concerted companion(CC)dyes for fabricating high-performance DSSCs,three organic dyes XL1-XL3 have been designed by varying the position and number of theβ-hexylthiophene(HT)bridges,and these organic dye units are covalently linked with our previously reported porphyrin dye XW10 to construct the corresponding CC dyes XW74-XW76.Among the organic dyes,XL3 contains twoβ-hexylthiophene units at both the donor and acceptor parts and thus possesses stronger light-harvesting capability in the green light region.Because of the most complementary absorption between XL3 and XW10 as well as the excellent photovoltaic behavior of the individual XL3 dye,the corresponding CC dye XW76 affords the best PCE(10.78%)among all the CC dyes.Upon coadsorption with CDCA,XW76 affords a highest PCE of 11.35%,which outperforms the previous cosensitization system of XW10+WS-5.This work provides an approach for developing efficient DSSCs based on CC dyes composed of an organic dye unit with suitableπspacers inserted at appropriate positions.展开更多
A polymer-bound photosensitizer was synthesized by the reaction of Merrifield resin with 9-anthracenemethanol in the presence of potassium hydride. The photoisomerization of trans-vitamin D3 to cis-vitamin D3 was car...A polymer-bound photosensitizer was synthesized by the reaction of Merrifield resin with 9-anthracenemethanol in the presence of potassium hydride. The photoisomerization of trans-vitamin D3 to cis-vitamin D3 was carried out with this polymer-bound photosensitizer in ethanol and toluene solutions. The experiment results demonstrate that this solid photosensitizer is efficient for the photoismerization and easy for separation from the reaction mixtures.展开更多
Three new metal-free organic dyes (TX1, TX2 and TX3) based on truxene core structure, with triphenylamine as the electron donor, thiophene as the n spacers, and cyanoacetic acid or rhodanine-3- acetic acid as the el...Three new metal-free organic dyes (TX1, TX2 and TX3) based on truxene core structure, with triphenylamine as the electron donor, thiophene as the n spacers, and cyanoacetic acid or rhodanine-3- acetic acid as the electron acceptor are designed and synthesized. Their UV-vis absorption spectra, electrochemical and photovoltaic properties were investigated. The cyanoacrylic acid is verified to be a better acceptor unit (meanwhile the anchoring group) compared to the rhodanine-3-acetic acid. And also, two anchoring groups in TX2 could provide stronger adsorption ability on the TiO2 surface. In addition, the EIS results indicate a slower charge recombination processes for TX2. As a result, dye TX2 bearing two cyanoacetic acid outperforms the other two dyes, exhibiting the photo-conversion efficiency of 2.64%, with Jsc = 5.09 mAcm^-2, Voc = 729 mV, FF = 71.1.展开更多
To ensure the infiltration of spiro-OMeTAD into the quantum dot-sensitized photoanode and to consider the limit of the hole diffusion length in the spiro-OMeTAD layer,a rutile TiO2 nanorod array with a length of 200 n...To ensure the infiltration of spiro-OMeTAD into the quantum dot-sensitized photoanode and to consider the limit of the hole diffusion length in the spiro-OMeTAD layer,a rutile TiO2 nanorod array with a length of 200 nm,a diameter of 20 nm and an areal density of 720 ram 2 was successfully prepared using a hydrothermal method with an aqueous-grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170℃for 75 min.PbS quantum dots were deposited by a spin coating-assisted successive ionic layer adsorption and reaction(spin-SILAR),and all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells were fabricated using spiro-OMeTAD as electrolytes.The results revealed that the average crystal size of PbS quantum dots was-78 nm using Pb(NO3)2 as the lead source and remain unchanged with the increase of the number of spin-SILAR cycles.The all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells with spin-SILAR cycle numbers of 20,30 and 40 achieved the photoelectric conversion efficiencies of 3.74%,4.12%and 3.11%,respectively,under AM 1.5 G illumination(100 mW/cm2).展开更多
基金financially supported by the National Natural Science Foundation of China(No.21908092)the Natural Science Foundation of Jiangsu Province(No.BK20242043)+2 种基金the China Postdoctoral Science Foundation(No.2022M711614)Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB194)the Fundamental Research Funds for the Central Universities at NUAA(No.NZ2024038)
文摘Nuclear energy provides a competitive path for reduction of CO_(2)with water,whereas the high-efficiency utilization of radioly tic ally produced active species for oriented transformation remains challenging.Herein,we report the assembling of yttrium-decorated bimetallic MOFs via one-step hydrothermal strategy,which can act as a sensitized nanoreactor for syngas production under y-ray irradiation.The flower-shaped CuNi-MOF matrix with tunable metal centers exposed plentiful cooperative active sites for CO_(2)binding,and its nanopetals enabled the well dispersion of Y_(2)O_(3)nanoparticles on the surfaces.The introduction of high-Z element Y enhanced the secondary electron scattering and promoted the water radiolysis to produce more hydrated electrons(e_(aq)^(-)),thus accelerating the initial CO_(2)activation to CO_(2)^(·-).Moreover,the in situ formed coupling interlayer provided a fast charge transfer channel between Y_(2)O_(3)and the MOF framework,which facilitated the interfacial electron migration for intermediate generation and subsequent CO_(2)conversion.By regulating the contents of Cu and Y_(2)O_(3)within the nanocomposites,the affinity toward CO_(2)and the product compositions could be modulated.As a result,the optimal 7CN-2Y catalyst achieved a high syngas evolution rate of 311.07μmol g^(-1)with a H_(2)/CO ratio of 2.7:1 at an absorbed dose of 4 kGy.The present study offered a feasible route for the efficient transformation of CO_(2)into valuable chemicals and the design of viable catalysts for ionizing radiation.
基金the financial support of the National Natural Science Foundation of China(Nos.52375339 and 52305399)the Basic and Applied Basic Research Program of Guangdong Province(No.2021A1515110729).
文摘The precipitation behavior,corrosion,and passivation performance of solutionized and severely sensitized SAF 2507 super-duplex stainless steel subjected to a temperature of 900℃for 10 h are investigated in a twofold concentrated seawater at 60℃.The sensitized alloy exhibits 66.1%γphases and 33.9%σphases,and the originalαphases have completely decomposed through eutectoid transformation,resulting in a microstructure characterized by coarse blockyσ/γ2 aggregates.High defect densities and an increased amount of oxyhydroxides and hydroxides are present in the passive film on the sensitized alloy,thereby enhancing n-type semiconducting character.The inferior performance of the passive film on the sensitized alloy is ascribed to the increased potential drop across the film/solution interface,the high defect densities,and the pronounced n-type character of the passive film resulting from the variations in its constituents.The precipitation ofσphase during sensitization significantly increases intergranular corrosion susceptibility and decreases critical pitting temperature,breakdown potential,and polarization resistance in hot concentrated seawater.
基金Central Public-interest Scientific Institution Basal Research Fund,ECSFR,CAFS(No.2018T02)the National Natural Science Foundation of China(Nos.21772041,21811530005,21971063,U1707602)the Fundamental Research Funds for the Central Universities(Nos.WK1616004,222201717003)。
文摘To achieve high power conversion efficiency(PCE),three porphyrin sensitizers have been synthesized and explored to simultaneously enhance the photocurrent(JSC)and photovoltage(VOC).On basis of the XW4,a benzothiadiazole(BTD)unit has been introduced to afford XW57 with the aim to extend the absorption wavelength and enhance the light harvesting ability.As a result,a JSC of 13.72 mA/cm^2 has been obtained for XW57,higher than that of XW4.On this basis,XW58 has been prepared by modifying the carbazole-based donor with two bulky dihexyloxyphenyl groups,and the superior anti-aggregation character raises the VOC from 781 mV(XW4)to 844 mV.When both the BTD unit and the bulky groups are introduced to the acceptor and donor units,respectively,the resulting sensitizer XW59 exhibits a highest PCE value of 7.34%with synergistically enhanced JSC of 13.19 mA/cm^2 and VOC of 793 mV.These results provide further insight into developing high performance dye-sensitized solar cells.
文摘The research on sensitizer for dye sensitized solar cells based on (metallo)porphyrin/phthalocyanine materials were reviewed, and experimental design and assembly method were advised. Latest progress and research status of sensitizer dyes based on metalloporphyrins applied in dye sensitized solar cells was summarized. The preparation and construction of sensitizer electrodes and dye sensitized solar cells based on metal organic frameworks (MOFs) of (metallo)porphyrin/phthalocyanine were projected.
文摘Fresh leaves of oil bean (P. macrophylla) were used as sensitizers for fabrication of dye sensitized solar cells (DSSCs) at four dye pH values of 2.58°C at 23.7°C, 2.62°C at 22.2°C, 2.65°C at 22.3°C and 3.61°C at 22.1 °C. The methanol extracts of P. macrophylla were extracted and used as sensitizers for the development of dye sensitized solar cells. The solar cells sensitized by P. macrophylla leaf extracts realised up to short circuit current (Jsc) 0.16 mA/cm2, open circuit voltage (Voc) 0.045 V, Pmax 0.031 mW/ cm2 and fill factor (FF) 0.50. The energy conversion efficiency (η) of the DSSCs is 0.43%. Phytochemical screening of P. macrophylla leaf extract shows the presence of flavonoids and anthraquinones. The nanostructured dye shows conversion of solar energy into electricity using low cost natural dyes as wide band-gap semiconductor sensitizers in DSSCs. This will provide economically viable substitute to silicon p-n junction photovoltaic (PV).
文摘Dye-sensitized solar cells (DSSC) were fabricated with mango leaf dye extracts as natural dye sensitizers at pH value of 5.20 and temperature of 18.1°C. Methanol was used as dye-extracting solvent. DSSCs from dye extract of M. indica L. with KMnO4 electrolyte had the highest photocurrent density of 1.3 mA/cm2 and fill factor FF of 0.46 for the sun at its peak. Potassium permanganate (KMnO4) had a photocurrent density of 1.3 mA/cm2 and FF of 0.8 at sundown. Potassium Iodide (KI), Potassium Bromide (KBr) and Mercury Chloride (HgCl2) electrolytes had 0.2 mA/cm2, 0.08 mA/cm2 and 0.02 mA/cm2 photocurrent densities respectively. The fill factors of 0.09, 0.03 and 0.003 respectively for sun overhead while 0.08 mA/cm2, 0.01 mA/cm2 and 0.01 mA/cm2 were the values of photocurrent densities respectively at sundown. The fill factors were 0.02, 0.0006 and 0.003 respectively at sundown. The maximum power Pmax of the DSSCs were 0.5 mW/cm2, 0.10 mW/cm2, 0.01 mW/cm2 and 0.012 mW/cm2 respectively at 1300 h at 1630 h 0.9 mW/cm2, 0.14 mW/cm2, 0.005 mW/cm2 and 0.0015 mW/cm2 respectively.
基金financially supported by the Beijing Municipal High Level Innovative Team Building Program (No. IDHT20180504)the National Natural Science Foundation of China (Nos. 21805004, 21671011, 21872001 and 51801006)+3 种基金Beijing Natural Science Foundation (No. KZ201710005002 and 2192005)the Natural Science Foundation of the Beijing Municipal Education Committee, China Postdoctoral Science Foundation (No. 2018M641133)Beijing Postdoctoral Research Foundation (No. 2018-ZZ-021)Chaoyang District Postdoctoral Research Foundation (No. 2018-ZZ-026)
文摘Carbon dots(Cdots)with a broad light absorption range could be a potential stable sensitizer for TiO2,which is an excellent ultraviolet(UV)response photocatalyst.Herein,we systematically investigated the different color emissive Cdots-sensitized TiO2 for H2 production.Firstly,all kinds of Cdots enhanced the photocatalytic properties of TiO2.All the Cdots-sensitized TiO2 exhibits visible light H2 production due to their absorption in the visible light region.The photocurrent and H2 production amount display strong dependence on the light absorption range of Cdots.The blue-emissive Cdots endow the weak H2 production rate due to its weak absorption in the visible light.The enhanced photocatalytic activities are mainly contributed to the strong light absorbance and high-efficient charge separation.The light absorption of green-and red-emissive Cdots is another main factor for the high catalytic activities besides charge separation.
文摘Non-alcoholic fatty liver disease(NAFLD) is the leading cause of liver disease in the Western world and is closely associated with metabolic syndrome,which includes hypertension,central obesity,dyslipidemia and insulin resistance.NAFLD includes a wide spectrum of liver alterations,ranging from simple hepatic steatosis to variable degrees of fibrosis,cirrhosis and even hepatocellular carcinoma.Although the etiology and progression of the disorder remain poorly understood,insulin resistance is considered to play a pivotal role in the pathogenesis.Insulin sensitizers such as biguanides,thiazolidinediones(TZDs),glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase 4 inhibitors have been studied as therapeutic approaches for NAFLD in recent years.Metformin improves insulin sensitivity and serum alanine transaminase and aspartate transaminase(ALT/AST) levels in the majority of subjects; however,it has no significant effect on liver histology.TZDs improve insulin sensitivity,serum ALT/ AST levels and histology in some cases,but there are some concerns about the safety of long-term therapy.Selection of appropriate patients for avoiding side effects and the treatment of underlying disease are themain points.These drugs are the best choice for the treatment of NAFLD in patients with type 2 DM who are also candidates for treatment with an insulin sensitizer.The present review provides an overview of insulin sensitizers in the treatment of NAFLD.
基金financially supported by the National Natural Science Foundation of China(No.21171091)the Natural Science Foundation of Higher Education Institutions in Anhui Province(Nos.KJ2012A217,KJ2012B135,and KJ2012B136)
文摘BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The photocatalytic activities of the catalysts were evaluated for the degradation of methyl orange (MO) solution under UV and visible light irradiation. The effects of catalyst amount, initial pH value, initial concentration of MO, as well as KI amount were investigated. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst was also tested. It is shown that BiOI sensitization enhances the photocatalytic activities of TiO2. With BiOI content increasing, the photocatalytic activities of BiOI/TiO2 under UV and visible light irradiation first increase, reaching a maximum around BiOI content of 1.7%, and then decrease with further increasing BiOI content. The 1.7% BiOI/TiO2 catalyst obviously exhibits much higher visible light photocatalytic activity than P25, and its UV light photocatalytic activity is slightly higher than that of P25. Under the conditions of a catalytic dose of 1.5 g.L-1, initial pH of 3.0, initial MO concentration of 20 mg.L-1, UV power of 300 W, and air flow rate of 0.8 L.min-1, complete degradatio is achieved within 60 min. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst is highly reliable.
基金supported by grant No.98U587 from Abadan University of Medical Sciences。
文摘Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadolinium(Ⅲ) coordination complex,[Gd_(2)(DPDB)_6(DMF)_6(H_(2)O_()2)](DPDB=[(4-dimethylamino)phenyldiazenyl] benzenesulfonate),which was used as an inorganic sensitizer for boosting the visible light-harvesting and quantum efficiency of TiO_(2) supported-reduced graphene oxide(rGO) nanocomposite.Crystal structure of [Gd_(2)(DPDB)_6(DMF)_6(H_(2)O)_(2)](Gd-CMP) was determined from single-crystal X-ray diffraction data,which indicates three-dimensional(3D) supramolecular architecture through hydrogen bonding and CH…π_(ph) interactions.The prepared nanohybrid(Gd-CMP/TG) reveals significantly enhanced visible-light-induced photocatalytic activity for degradation of acetaminophen(ACT).The complete removal of 10 mg/L ACT is achieved over Gd-CMP/TG,and the corresponding rate constant of ACT degradation of nanohybrid is 40-fold higher than that of bare TiO_(2).In prepared ternary nanohybrid,metal-coordination sensitizer(Gd-CMP) acts as an electron donor,and at the same time,rGO serves as an electron acceptor,and the synergistic effect between them efficiently enhances charges separation and inhibits e/h pair recombination in the hybridized species.The radical scavenger tests indicate that the photo-induced O_(2)^(-·) radicals dominate ACT degradation.On the basis of the experimental results and calculated energy of electronic levels,a possible mechanism for the improved photocatalytic activity is discussed.
基金Project supported by National Natural Science Foundation of China(21425101,21331001,21371011)Ministry of Science and Technology of China(2014CB643800)
文摘The past few years witnessed extensive emergence of short-wavelength upconversion(UC)emission stimulated photoactivation studies.However,low efficiency of multi-photon process greatly limits further applications.Here,ultraviolet(UV)upconversion emissions originated from multi-photon process of Tm^3+were studied with Nd^3+-sensitized NaGdF4:Yb,Tm@NaYF4:Nd,Yb core/shell nanoparticles.Crucial factors,including the contents of sensitizers Nd^3+,Yb^3+and activator Tm^3+,as well as the excitation power density were investigated based on the UV emission.Spectral results showed that high contents of Nd^3+in shell region up to 50%(molar fraction hereafter)and Yb^3+of 10%were essential to mediate the energy transfer via the core/shell interface and facilitate multi-photon UV emissions.Compared with segregated activator and sensitizer,a core/shell strategy with isolated Nd^3+in the shell was important for higher UV emission.Although the upconverting process was initiated with Nd^3+→Yb^3+,the short-wavelength emissions were intrinsically coming from four-and five-photon process.The optimized nanoparticles were found to be able to manipulate the configuration transition of azobenzene molecules,and it could be promising for near infrared(NIR)triggered optical switches applications.
文摘Titania is one kind of important materials, which has been extensively investigated because of its unique electronic and optical properties. Research efforts have largely focused on the optimization of the dye,but recently the titania nanostructures electrode itself has attracted more attention. It has been shown that particle size, shape, crystallinity, surface morphology, and chemistry of the TiO_2 material are key parameters which should be controlled for optimized performance of the solar cell. Titania can be found in different shape of nanostructures including mesoporous, nanotube, nanowire, and nanorod structures. The present article reviews the structural, synthesis, electronic, and optical properties of TiO_2 nanostructures for dye sensitized solar cells.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2017RIA2B4006388,NRF-2017R1D1A3B03035530)
文摘Upconversion phosphors are known as a material system that can convert near-infrared light into visible/ultraviolet emissions by sequentially absorbing multiple photons. The studies on upconversion materials often use two rare earth(RE) ions as a sensitizer-activator pair. We investigated the influences on luminescence intensity depending on Cr-doping content(x) of hexagonal NaLu_(0.98-x)Cr_xF4 Er_(0.02)(x = 0-0.9)upconversion material by substituting Lu^(3+) ions with Cr^(3+)in the absence of Gd^(3+). The change in upconversion luminescence intensity appears with saddle-like shape. We suggest that Cr^(3+) ions play the dual role as a constituent in host lattice and a sensitizer in the upconversion process. Optimal conditions for gaining the strongest upconversion emission correspond to x = 0.3-0.5, where there are effective energy transfers between Cr^(3+) and Er^(3+) ions and Cr-Er dimers. Apart from these values, the emission intensity decreases rapidly which can be ascribed to the absence of multiple-photon absorption for the case of low Cr^(3+) contents, and to the coupling between Cr^(3+) and/or Er^(3+) ions for the case of high Cr^(3+)contents. Magnetization and electron-spin-resonant measurements were performed to understand the correlation between the optical and magnetic properties.
基金Supported by the MMH grant from Mackay Memorial Hospital, No. 9252
文摘AIM: We studied the effect of colchicine combined with radiation on the survival of human hepatocellular carcinoma (HCC) HA22T/VGH cells.METHODS: Twenty-four hours after treatment with 0-8 ng/mL colchicine, HA22T/VGH cells were irradiated at various doses (0, 1, 2, 4, and 8 Gy). Colony assay was performed to assess the surviving cell fraction. Survival curves were fitted by using a linear-quadratic model to estimate the sensitizer enhancement ratio (SER). Flow cytometry was used for cell cycle analysis.RESULTS: Colchicine at lower concentrations (1 and 2 ng/mL) had obvious synergy with radiation to inhibit HCC cell growth, whereas higher concentrations (4 and 8 ng/mL) had only additive effect to radiation. Pretreatment with 1 and 2 ng/mL colchicine for 24-h enhanced cell killing by radiation with SERs of 1.21 and 1.53, respectively.G2/N arrest was only observed with higher colchicine doses (8 and 16 ng/mL) after 24-h treatment, this effect was neither seen with lower doses (1, 2, and 4 ng/mL)nor with any dose after only 1 h of treatment.CONCLUSION: Our results suggest that colchicine has potential as an adjunct to radiotherapy for HCC treatment.Lower doses of colchicine possess radiosensitizing effects via some mechanism other than G2/M arrest. Further study is necessary to elucidate the mechanism.
基金supported by National Research Fund for High-Tech Research and Development of China Program(No. 2007AA05Z439)
文摘The pure TiO2 and Fe salts [Fe(C2O4)3,5H2O]-doped TiO2 electrodes were prepared by the hydrothermal method. The pure TiO2 or Fe-doped TiO2 slurry was coated onto the fluorine-doped tin oxide glass substrate by the Doctor Blade method and then sintered at 450 ℃. The Mott-Schottks, plot indicates that the fiat band potential of TiO2 was shifted positively after Fe-doped TiO2. The positive shift of the fiat band potential improves the driving force of injected electrons from the LUMO of the dye to the conduction band of TiO2. This study shows that photovoltaic efficiency increased by 22.9% from 6.07% to 7.46% compared to pure TiO2, and the fill factors increased from 0.53 to 0.63.
基金Project(8451063201001261) supported by the Guangdong Natural Science Fund Committee,ChinaProject(LYM08022) supported by the Foundation for Distinguished Young Talents in Higher Education of Guangdong,China+1 种基金Project (2007A032400001, 2008A030202010) supported by the Scientific and Technological Planning of Guangdong Province,ChinaProject(216113132) supported by the Scientific Research Cultivation and Innovation Fund, Jinan University,China
文摘The role of oxygen and the generation of active radicals in the photocatalitic degradation of phenol were investigated using the eosin sensitized TiO2 as photocatalyst under visible light irradiation. Diffuse reflectance spectra show that the absorbancy range of eosin/TiO2 is expanded from 378 nm (TiO2 ) to about 600 nm. The photocatalitic degradation of phenol is almost stopped when the eosin/TiO2 system is saturated with N2 , which indicates the significance of O2 . The addition of NaN 3 (a quencher of single oxygen) causes about a 62% decrease in the phenol degradation. The phenol degradation ratio is dropped from 92% to 75% when the isopropanol (a quencher of hydroxyl radical) is present in the system. The experimental results show that there are singlet oxygen and hydroxyl radical generated in the eosin/TiO2 system under visible light irradiation. The changes of absorbancy indicate that the hydrogen peroxide might be produced. Through the analysis and comparison, it is found that the singlet oxygen is the predominant active radical for the degradation of phenol.
基金financially supported by the National Natural Science Foundation of China (Nos. 22131005, 21772041, 21971063 and 22075077)the Program of Shanghai Academic Research Leader (No. 20XD1401400)+1 种基金the Natural Science Foundation of Shanghai (No. 20ZR1414100)the Fundamental Research Funds for the Central Universities (No. 222201717003)
文摘To develop efficient concerted companion(CC)dyes for fabricating high-performance DSSCs,three organic dyes XL1-XL3 have been designed by varying the position and number of theβ-hexylthiophene(HT)bridges,and these organic dye units are covalently linked with our previously reported porphyrin dye XW10 to construct the corresponding CC dyes XW74-XW76.Among the organic dyes,XL3 contains twoβ-hexylthiophene units at both the donor and acceptor parts and thus possesses stronger light-harvesting capability in the green light region.Because of the most complementary absorption between XL3 and XW10 as well as the excellent photovoltaic behavior of the individual XL3 dye,the corresponding CC dye XW76 affords the best PCE(10.78%)among all the CC dyes.Upon coadsorption with CDCA,XW76 affords a highest PCE of 11.35%,which outperforms the previous cosensitization system of XW10+WS-5.This work provides an approach for developing efficient DSSCs based on CC dyes composed of an organic dye unit with suitableπspacers inserted at appropriate positions.
文摘A polymer-bound photosensitizer was synthesized by the reaction of Merrifield resin with 9-anthracenemethanol in the presence of potassium hydride. The photoisomerization of trans-vitamin D3 to cis-vitamin D3 was carried out with this polymer-bound photosensitizer in ethanol and toluene solutions. The experiment results demonstrate that this solid photosensitizer is efficient for the photoismerization and easy for separation from the reaction mixtures.
基金supported by‘‘Fundamental Research Funds for the Central Universities’’(Nos.XDJK2014C145 and XDJK2014C052)the Starting Foundation of Southwest University(Nos.SWU113076 and SWU113078)the financial support from National Natural Science Foundation of China(No.51203046)
文摘Three new metal-free organic dyes (TX1, TX2 and TX3) based on truxene core structure, with triphenylamine as the electron donor, thiophene as the n spacers, and cyanoacetic acid or rhodanine-3- acetic acid as the electron acceptor are designed and synthesized. Their UV-vis absorption spectra, electrochemical and photovoltaic properties were investigated. The cyanoacrylic acid is verified to be a better acceptor unit (meanwhile the anchoring group) compared to the rhodanine-3-acetic acid. And also, two anchoring groups in TX2 could provide stronger adsorption ability on the TiO2 surface. In addition, the EIS results indicate a slower charge recombination processes for TX2. As a result, dye TX2 bearing two cyanoacetic acid outperforms the other two dyes, exhibiting the photo-conversion efficiency of 2.64%, with Jsc = 5.09 mAcm^-2, Voc = 729 mV, FF = 71.1.
基金supported by the National Natural Science Foundation of China(51272061,51472071)
文摘To ensure the infiltration of spiro-OMeTAD into the quantum dot-sensitized photoanode and to consider the limit of the hole diffusion length in the spiro-OMeTAD layer,a rutile TiO2 nanorod array with a length of 200 nm,a diameter of 20 nm and an areal density of 720 ram 2 was successfully prepared using a hydrothermal method with an aqueous-grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170℃for 75 min.PbS quantum dots were deposited by a spin coating-assisted successive ionic layer adsorption and reaction(spin-SILAR),and all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells were fabricated using spiro-OMeTAD as electrolytes.The results revealed that the average crystal size of PbS quantum dots was-78 nm using Pb(NO3)2 as the lead source and remain unchanged with the increase of the number of spin-SILAR cycles.The all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells with spin-SILAR cycle numbers of 20,30 and 40 achieved the photoelectric conversion efficiencies of 3.74%,4.12%and 3.11%,respectively,under AM 1.5 G illumination(100 mW/cm2).