To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a fle...To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a flexible chain,which exhibits panchromatic absorption and excellent anti-aggregation ability.To further improve the absorption,we herein report XW87 and XW88 by inserting an ethynyl group into the organic sub-dye unit of XW83 near the donor and acceptor,respectively.For the corresponding organic dyes Z3 and Z4,the introduced ethynyl group improves their absorption,but induces aggravated charge recombination,leading to lowered power conversion efficiencies(PCEs).Similar to the organic dyes,the introduced ethynyl group improves the absorption of DCC dyes XW87 and XW88 as well.In addition,the ethynyl group near the acceptor of the organic sub-dye unit can be well protected by the long wrapping chains from the porphyrin unit.As a result,XW88 affords the highest JSC(21.84 mA/cm^(2)),V_(OC)(782 mV)and PCE(12.2%)among the DCC dyes.These results provide an effective method for developing efficient DSSC dyes by inserting an ethynyl group at a suitable position of a DCC dye.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
Dye sensitization is a fundamental function for solar cell and silver halide (AgX) microcrystal to increase the optoelectronic conversion efficiency. In this paper, the spectral properties and self-assembled structure...Dye sensitization is a fundamental function for solar cell and silver halide (AgX) microcrystal to increase the optoelectronic conversion efficiency. In this paper, the spectral properties and self-assembled structure of three types of cyanine dyes, adsorbed both on (100) surface of 0.4 μm AgBr cubic crystal and (111) surface of 1.8 μm AgBr tabular crystal, were studied with combination of spectroscopy and atomic force microscopy (AFM) technique. Rectangular aggregation structure is formed on the crystal faces of (100) and (111) for both anionic and cationic dyes, while herringbone-stacking structure is formed by anionic-cationic dye, and a J-band spectrum is correspondingly detected. The photoelectron property of dye-sensitized samples was also investigated with microwave absorption and dielectric spectrum detection technology. After excited by a 355 nm fast-pulse laser, the photoelectron decay process of anionic-cationic dye sensitized sample is the fastest. This indicates that the affection of anionic-cationic dye aggregates to the photoelectron decay is the biggest, and the sensitization is more efficient.展开更多
A series of new metal-free organic dyes that contain donors with triphenylamine or its derivatives and tetrazole-based acceptors were synthesized and characterized by photophysical, electrochemical, and the- oretical ...A series of new metal-free organic dyes that contain donors with triphenylamine or its derivatives and tetrazole-based acceptors were synthesized and characterized by photophysical, electrochemical, and the- oretical computational methods. They were applied in nanocrystalline TiO2 solar cells （DSSCs）. It is found that the introduction of diphenylamine units as antennas in the as-synthesized dyes could improve photo- voltaic performance compared with phenothiazine and carbazole units as antennas in DSSCs. The dye with （2H-tetrazol-5-yl） acrylonitrile electron acceptor also displayed the highest solar-to-electrical energy conver- sion efficiency.展开更多
Hydrogen energy(H_(2)) has been considered as the most possible consummate candidates for replacing the traditional fossil fuels because of its higher combustion heat value and lower environmental pollution.Photocatal...Hydrogen energy(H_(2)) has been considered as the most possible consummate candidates for replacing the traditional fossil fuels because of its higher combustion heat value and lower environmental pollution.Photocatalytic hydrogen evolution(PHE) from water splitting based on semiconductors is a promising technology towards converting solar energy into sustainable H_(2)fuel evolution. Developing high-activity and abundant source semiconductor materials is particularly important to realize highly efficient hydrogen evolution as for photocatalysis technology. However, unmodified pristine photocatalysts are often unable to overcome the weakness of low performance due to their limitations. In recent years, transition metal phosphides(TMPs) were used as valid co-catalysts to replace the classic precious metal materials in the process of photocatalytic reaction owing to their lower cost and higher combustion heat value.What is more, bimetallic phosphides have been also caused widespread concern in H_(2)evolution reaction owing to its much lower overpotential, more superior conductivity, and weaker charge carriers transfer impedance in comparison to those of single metal phosphides. In this minireview, we concluded the latest developments of bimetallic phosphides for a series of photocatalytic reactions. Firstly, we briefly summarize the present loading methods of bimetallic phosphides(BMPs) anchored on the photocatalyst. After that, the H;evolution efficiency based on BMPs as cocatalyst is also studied in detail. Besides, the application of BMPs-based host photocatalyst for H_(2)evolution under dye sensitization effect has also been discussed. At last, the current development prospects and prospective challenges in many ways of BMPs are proposed. We sincerely hope this minireview has certain reference value for great developments of BMPs in the future research.展开更多
A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine deri...A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3Py+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer.展开更多
Lanthanide-doped biocompatible nanoparticles have promising applications in near-infrared second region imaging due to their high chemical stability,enhanced photostability and sharp emission bandwidth.However,the wea...Lanthanide-doped biocompatible nanoparticles have promising applications in near-infrared second region imaging due to their high chemical stability,enhanced photostability and sharp emission bandwidth.However,the weak light absorption capacity limits the application of rare-earth nanoparticles(RENPs) for bioimaging.We prepared a coumarin-derived dye sensitized NaYGdF4:Yb,Er nanoparticle probe,in which the organic dye enhances photon absorption through the sensitization process,improving the luminescence efficiency of the rare earth particles near 1000 and 1500 nm.In addition,good water solubility and stability of the probe are imparted by coating the particles with amphiphilic polymers distearoyl phosphatidylethanolamine-polyethylene glycol(DSPE-PEG) and polyacrylic acid.This composite probe with good biocompatibility and NIR Ⅱ luminescence properties can be used for vascular imaging,providing a tool for the detection of hematologic-related diseases.展开更多
Although Bi_(2)Mo O_(6)(BMO) has recently received extensive attention, its visible-light photocatalytic activity remains poor due to its limited photoresponse range and low charge separation efficiency. In this work,...Although Bi_(2)Mo O_(6)(BMO) has recently received extensive attention, its visible-light photocatalytic activity remains poor due to its limited photoresponse range and low charge separation efficiency. In this work, a series of visible-light-driven Y^(3+)-doped BMO(Y-BMO) photocatalysts were synthesized via a hydrothermal method. Degradation experiments on Rhodamine B and Congo red organic pollutants revealed that the optimal degradation rates of Y-BMO were 4.3 and 5.3 times those of pure BMO, respectively. The degradation efficiency of Y-BMO did not significantly decrease after four cycle experiments. As a result of Y^(3+)doping, the crystal structure of BMO changed from a thick layer structure to a thin flower-like structure with an increased specific surface area. X-ray photoelectron spectroscopy showed the presence of highintensity peaks for the O 1s orbital at 531.01 and 530.06 eV, confirming the formation of oxygen vacancies in Y-BMO. Photoluminescence(PL) and electrochemical impedance spectroscopy measurements revealed that the PL intensity and interface resistances of composites decreased significantly, indicating reduced electron–hole pair recombination. This work provides an effective way to prepare high-efficiency Bibased photocatalysts by doping rare earth metal ions for improved photocatalytic performance.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
Light utilization is one of the key factors for the improvement of photocatalytic perfo rmance.He rein,we design C-TiO_(2) hollow nanoshells with strong Mie resonance for enhanced photocatalytic hydrogen evolution in ...Light utilization is one of the key factors for the improvement of photocatalytic perfo rmance.He rein,we design C-TiO_(2) hollow nanoshells with strong Mie resonance for enhanced photocatalytic hydrogen evolution in a dye-sensitized system under visible light irradiation(λ≥420 nm).By tuning the inner diameters of hollow nanoshells,the Mie resonance in hollow nanoshells is adjusted for better excitation of dye molecules,which thus greatly enhances the light utilization in visible light region.This work shows the potential of Mie resonance in nanoshells can be an alternative strategy to increase the light utilization for photocatalysis.展开更多
Solution processible photovoltaics(PV)are poised to play an important role in scalable manufacturing of low-cost solar cells.Electrospray is uniquely suited for fabricating PVs due to its several desirable characteris...Solution processible photovoltaics(PV)are poised to play an important role in scalable manufacturing of low-cost solar cells.Electrospray is uniquely suited for fabricating PVs due to its several desirable characteristics of an ideal manufacturing process such as compatibility with roll-to-roll production processes,tunability and uniformity of droplet size,capability of operating at atmospheric pressure,and negligible material waste and nano structures.This review begins with an introduction of the fundamentals and unique properties of electrospray.We put emphasis on the evaporation time and residence time that jointly affect the deposition outcome.Then we review the efforts of electrospray printing polymer solar cells,perovskite solar cells,and dye sensitized solar cells.Collectively,these results demonstrate the advantages of electrospray for solution processed PV.Electrospray has also exhibited the capability of producing uniform films as well as nanostructured and even multiscale films.So far,the electrospray has been found to improve active layer morphology,and create devices with efficiencies comparable with that of spin-coating.Finally,we discuss challenges and research opportunities that enable electrospray to become a mainstream technique for industrial scale production.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
Metal oxide mesocrystals(MCs)and mesoporous single crystals(MSCs)exhibit superior carrier transport ability,high specific surface area,shortened photo-carrier diffusion lengths to interfaces and enhanced absorbance of...Metal oxide mesocrystals(MCs)and mesoporous single crystals(MSCs)exhibit superior carrier transport ability,high specific surface area,shortened photo-carrier diffusion lengths to interfaces and enhanced absorbance of the incident sunlight.These advanced features make metal oxide MCs and MSCs be a promising candidate material in photocatalysis,photoelectrocatalysis,dye sensitized solar cells(DSSCs)and perovskite solar cells(PSCs).Recently,remarkable advances of applying metal oxide MCs and MSCs in these areas have been achieved.Therefore,it is extremely important to deeply understand the influence of the unique properties of metal oxide MCs and MSCs on solar energy conversion systems.Herein,we presented a brief introduction on the synthesis and carrier transfer behavior of metal oxide MCs and MSCs.Then,the rational structure design and modification of metal oxide MCs and MSCs for photocatalysis,photoelectrocatalysis,DSSCs and PSCs are systematically discussed.Finally,the perspectives on extending the application of metal oxide MCs and MSCs are addressed.展开更多
Converting solar energy into valuable hydrogen and hydrocarbon fuels through photoelectrocatalytic water splitting and CO2 reduction is highly promising in addressing the growing demand for renewable and clean energy ...Converting solar energy into valuable hydrogen and hydrocarbon fuels through photoelectrocatalytic water splitting and CO2 reduction is highly promising in addressing the growing demand for renewable and clean energy resources. However, the solar-to-fuel conversion efficiency is still very low due to limited light absorption and rapid bulk recombination of charge carriers. In this work, we present chlorophyll （Chl） and its derivative sodium copper chlorophyllin （ChlCuNa）, as dye sensitizers, modified BiVO4 to improve the photoelectrochemical （PEC） performance. The photocurrent of BiVO4 is surprisingly decreased after a direct sensitization of Chl while the sensitization of ChlCuNa obviously enhances photocurrent of BiV04 electrodes by improved surface hydrophilicity and extended light absorption. ChlCuNa-sensitized BiVO4 achieves an improved H2 evolution rate of 5.43/~molh l cm 2 in water splitting and an enhanced HCOOH production rate 0f2.15 p^mol h 1 cm 2 in CO2 PEC reduction, which are 1.9 times and 2.4 times higher than pristine BiV04, respectively. It is suggested that the derivative ChlCuNa is a more effective sensitizer for solar-to-fuel energy conversion and CO2 utilization than Chl.展开更多
Photoelectric property of polyaniline doped with dodecyl-benzene sulphonic acid (DBSA) is studied. The result shows that the concentration of carrier increases obviously, when polyaniline doped with DBSA is irradiated...Photoelectric property of polyaniline doped with dodecyl-benzene sulphonic acid (DBSA) is studied. The result shows that the concentration of carrier increases obviously, when polyaniline doped with DBSA is irradiated with light. Mixture of sensitive material is advantageous to the absorption of polyaniline in visible light spectrum, and the conductivity is also improved. The results of dielectric measurements on polyaniline doped with DBSA in an Al-PAn-DBSA-Al configuration as function of frequency and temperature are reported. The space-charge polarization phenomenon is observed. Carrier lifetime is microsecond magnitude and mobility is (0.001～0.1) cm 2/V·s, which are obtained by calculation or experiment. The active energy is obtained from the relation between conductivity and temperature. The conducting mechanism of PAn-DBSA is analyzed.展开更多
To sensitize polyaniline with dyes by electrochemical polymerization, HClO 4 is employed as the dopant and oxidant, and the polyaniline with different sensitive properties is synthesized. The effect of sensitized emer...To sensitize polyaniline with dyes by electrochemical polymerization, HClO 4 is employed as the dopant and oxidant, and the polyaniline with different sensitive properties is synthesized. The effect of sensitized emeraldine salt on the absorption spectrum is discussed in details. The maximum conductivity of sensitized films reaches 1.22 S/cm, and investigation on dye sensitizing of the polymer reveals that C.I. Direct Blue 71, C.I. Direct Blue 84, C.I. Direct Black 19 and CuPc-(COOH) 4 may enhance the photoconductivity of polyaniline greatly.展开更多
The photoelectron property is directly related to the light-energy conversion efficiency of solar cells. In this paper, the photoelectron dynamic of semiconductor was analyzed. The diffusion of electrons has influence...The photoelectron property is directly related to the light-energy conversion efficiency of solar cells. In this paper, the photoelectron dynamic of semiconductor was analyzed. The diffusion of electrons has influence on the dielectric function of the solar cell material. And the amplitude variance of the imaginary and real part of the dielectric function is in direct proportion to the dynamic process of free and shallow-trapped electrons. Based on the untouched detection technique, the method is present to detect the amplitude change of the microwave signal which is passing through the material whose dielectric function changes after exposure. A 35 GHz oscillator was used as a microwave source. The absorption and dispersion microwave signals, which contain the dynamic information of free and shallow-trapped electron signal, are split respectively with phase-sensitive instrument. The photoelectron character of n-type Si(100) thin film was investigated by the novel equipment, and the lifetime of different kinds of electrons with the resolution of 1 ns was obtained. The equipment can be directly used in the study of the optoelectronic conversion mechanism of solar cells.展开更多
The photoinitiating system composed of 1-ethyl-3'-methylthiacyanine bro-mide (C-I), 2-chlorohexaarylbiimidazole (o-Cl-HABI) and 3-mercapto-4-methyl-4H-1, 2, 4-triazole (MTA), which act as sensitizer, initiator and...The photoinitiating system composed of 1-ethyl-3'-methylthiacyanine bro-mide (C-I), 2-chlorohexaarylbiimidazole (o-Cl-HABI) and 3-mercapto-4-methyl-4H-1, 2, 4-triazole (MTA), which act as sensitizer, initiator and hydrogen-donor respectively, can beused to initiate the polymerization of methyl methacrylate (MMA). The kinetic study wascarried out in trichloromathane solution at 30℃ by using dilatometry. The relation be-tween the polymerization rate and the concentrations of C-I, o-Cl-HABI, MTA and MMAwas studied.展开更多
The geometries, electronic structures, polarizabilities and hyperpolarizabilities, as well as the UV-Vis spectra of the two organic dye sensitizers containing bis-dimethylfluorenyl amino benzofuran were studied via de...The geometries, electronic structures, polarizabilities and hyperpolarizabilities, as well as the UV-Vis spectra of the two organic dye sensitizers containing bis-dimethylfluorenyl amino benzofuran were studied via density functional theory （DFT） and time-dependent DFT. The features of electronic absorption spectra were assigned on account of the agreement between the experiment and the calculations. The absorption bands in visible region are related to photoinduced electron transfer processes, and the dimethylfluorenyl amino benzo[b]furan groups are major chromophore that contributed to the sensitization of photo-to-current conversion. The role of vinylene group in geometry, electronic structure and spectra property is analyzed according to the comparative study of the dyes.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.22131005,22201074,22075077 and 21971063)the Fundamental Research Funds for the Central Universities,Program of Shanghai Academic Research Leader(No.20XD1401400)+1 种基金Shanghai Rising-Star Program(No.23QA1402100)Natural Science Foundation of Shanghai(Nos.23ZR1415600,22ZR1416100).
文摘To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a flexible chain,which exhibits panchromatic absorption and excellent anti-aggregation ability.To further improve the absorption,we herein report XW87 and XW88 by inserting an ethynyl group into the organic sub-dye unit of XW83 near the donor and acceptor,respectively.For the corresponding organic dyes Z3 and Z4,the introduced ethynyl group improves their absorption,but induces aggravated charge recombination,leading to lowered power conversion efficiencies(PCEs).Similar to the organic dyes,the introduced ethynyl group improves the absorption of DCC dyes XW87 and XW88 as well.In addition,the ethynyl group near the acceptor of the organic sub-dye unit can be well protected by the long wrapping chains from the porphyrin unit.As a result,XW88 affords the highest JSC(21.84 mA/cm^(2)),V_(OC)(782 mV)and PCE(12.2%)among the DCC dyes.These results provide an effective method for developing efficient DSSC dyes by inserting an ethynyl group at a suitable position of a DCC dye.
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.
基金This work was financially supported by the National Natural Science Foundation of China (No.10274017)the Natural Science Foundation of Hebei Province, China (No.103097, E2005000131).
文摘Dye sensitization is a fundamental function for solar cell and silver halide (AgX) microcrystal to increase the optoelectronic conversion efficiency. In this paper, the spectral properties and self-assembled structure of three types of cyanine dyes, adsorbed both on (100) surface of 0.4 μm AgBr cubic crystal and (111) surface of 1.8 μm AgBr tabular crystal, were studied with combination of spectroscopy and atomic force microscopy (AFM) technique. Rectangular aggregation structure is formed on the crystal faces of (100) and (111) for both anionic and cationic dyes, while herringbone-stacking structure is formed by anionic-cationic dye, and a J-band spectrum is correspondingly detected. The photoelectron property of dye-sensitized samples was also investigated with microwave absorption and dielectric spectrum detection technology. After excited by a 355 nm fast-pulse laser, the photoelectron decay process of anionic-cationic dye sensitized sample is the fastest. This indicates that the affection of anionic-cationic dye aggregates to the photoelectron decay is the biggest, and the sensitization is more efficient.
文摘A series of new metal-free organic dyes that contain donors with triphenylamine or its derivatives and tetrazole-based acceptors were synthesized and characterized by photophysical, electrochemical, and the- oretical computational methods. They were applied in nanocrystalline TiO2 solar cells （DSSCs）. It is found that the introduction of diphenylamine units as antennas in the as-synthesized dyes could improve photo- voltaic performance compared with phenothiazine and carbazole units as antennas in DSSCs. The dye with （2H-tetrazol-5-yl） acrylonitrile electron acceptor also displayed the highest solar-to-electrical energy conver- sion efficiency.
基金supported by the National Natural Science Foundation of China (No. 52072153)the NSFC-Shanxi Coal Based Low Carbon Joint Fund (No. U1810117)+2 种基金the Natural Science Foundation of Jiangsu Province (No. BK20190867)Key Scientific Research Projects of Colleges and Universities in Henan Province (No.21A430024)the Young Talent Cultivate Programme of Jiangsu University (No. 4111310017)。
文摘Hydrogen energy(H_(2)) has been considered as the most possible consummate candidates for replacing the traditional fossil fuels because of its higher combustion heat value and lower environmental pollution.Photocatalytic hydrogen evolution(PHE) from water splitting based on semiconductors is a promising technology towards converting solar energy into sustainable H_(2)fuel evolution. Developing high-activity and abundant source semiconductor materials is particularly important to realize highly efficient hydrogen evolution as for photocatalysis technology. However, unmodified pristine photocatalysts are often unable to overcome the weakness of low performance due to their limitations. In recent years, transition metal phosphides(TMPs) were used as valid co-catalysts to replace the classic precious metal materials in the process of photocatalytic reaction owing to their lower cost and higher combustion heat value.What is more, bimetallic phosphides have been also caused widespread concern in H_(2)evolution reaction owing to its much lower overpotential, more superior conductivity, and weaker charge carriers transfer impedance in comparison to those of single metal phosphides. In this minireview, we concluded the latest developments of bimetallic phosphides for a series of photocatalytic reactions. Firstly, we briefly summarize the present loading methods of bimetallic phosphides(BMPs) anchored on the photocatalyst. After that, the H;evolution efficiency based on BMPs as cocatalyst is also studied in detail. Besides, the application of BMPs-based host photocatalyst for H_(2)evolution under dye sensitization effect has also been discussed. At last, the current development prospects and prospective challenges in many ways of BMPs are proposed. We sincerely hope this minireview has certain reference value for great developments of BMPs in the future research.
文摘A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3Py+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer.
基金Project supported by the National Natural Science Foundation of China (81801744)National Key R&D Program of China(2017YFA0205202,2017YFC1309100,2018YFC0910602)。
文摘Lanthanide-doped biocompatible nanoparticles have promising applications in near-infrared second region imaging due to their high chemical stability,enhanced photostability and sharp emission bandwidth.However,the weak light absorption capacity limits the application of rare-earth nanoparticles(RENPs) for bioimaging.We prepared a coumarin-derived dye sensitized NaYGdF4:Yb,Er nanoparticle probe,in which the organic dye enhances photon absorption through the sensitization process,improving the luminescence efficiency of the rare earth particles near 1000 and 1500 nm.In addition,good water solubility and stability of the probe are imparted by coating the particles with amphiphilic polymers distearoyl phosphatidylethanolamine-polyethylene glycol(DSPE-PEG) and polyacrylic acid.This composite probe with good biocompatibility and NIR Ⅱ luminescence properties can be used for vascular imaging,providing a tool for the detection of hematologic-related diseases.
基金financially supported by the National Natural Science Foundation of China (No.21271022)。
文摘Although Bi_(2)Mo O_(6)(BMO) has recently received extensive attention, its visible-light photocatalytic activity remains poor due to its limited photoresponse range and low charge separation efficiency. In this work, a series of visible-light-driven Y^(3+)-doped BMO(Y-BMO) photocatalysts were synthesized via a hydrothermal method. Degradation experiments on Rhodamine B and Congo red organic pollutants revealed that the optimal degradation rates of Y-BMO were 4.3 and 5.3 times those of pure BMO, respectively. The degradation efficiency of Y-BMO did not significantly decrease after four cycle experiments. As a result of Y^(3+)doping, the crystal structure of BMO changed from a thick layer structure to a thin flower-like structure with an increased specific surface area. X-ray photoelectron spectroscopy showed the presence of highintensity peaks for the O 1s orbital at 531.01 and 530.06 eV, confirming the formation of oxygen vacancies in Y-BMO. Photoluminescence(PL) and electrochemical impedance spectroscopy measurements revealed that the PL intensity and interface resistances of composites decreased significantly, indicating reduced electron–hole pair recombination. This work provides an effective way to prepare high-efficiency Bibased photocatalysts by doping rare earth metal ions for improved photocatalytic performance.
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Financial support for this project was provided by the National Natural Science Foundation of China (Nos.51702023,51702022)Natural Science Research of Jiangsu Higher Education Institutions of China (No.17KJB430001)。
文摘Light utilization is one of the key factors for the improvement of photocatalytic perfo rmance.He rein,we design C-TiO_(2) hollow nanoshells with strong Mie resonance for enhanced photocatalytic hydrogen evolution in a dye-sensitized system under visible light irradiation(λ≥420 nm).By tuning the inner diameters of hollow nanoshells,the Mie resonance in hollow nanoshells is adjusted for better excitation of dye molecules,which thus greatly enhances the light utilization in visible light region.This work shows the potential of Mie resonance in nanoshells can be an alternative strategy to increase the light utilization for photocatalysis.
基金X.Z.acknowledges the funding support from National Science Foundation of China(NSFC)(No.61975073 and No.61605076)W.D.thanks the financial support from NSFC(No.11872199 and No.11932009).
文摘Solution processible photovoltaics(PV)are poised to play an important role in scalable manufacturing of low-cost solar cells.Electrospray is uniquely suited for fabricating PVs due to its several desirable characteristics of an ideal manufacturing process such as compatibility with roll-to-roll production processes,tunability and uniformity of droplet size,capability of operating at atmospheric pressure,and negligible material waste and nano structures.This review begins with an introduction of the fundamentals and unique properties of electrospray.We put emphasis on the evaporation time and residence time that jointly affect the deposition outcome.Then we review the efforts of electrospray printing polymer solar cells,perovskite solar cells,and dye sensitized solar cells.Collectively,these results demonstrate the advantages of electrospray for solution processed PV.Electrospray has also exhibited the capability of producing uniform films as well as nanostructured and even multiscale films.So far,the electrospray has been found to improve active layer morphology,and create devices with efficiencies comparable with that of spin-coating.Finally,we discuss challenges and research opportunities that enable electrospray to become a mainstream technique for industrial scale production.
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supported by Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2020192)。
文摘Metal oxide mesocrystals(MCs)and mesoporous single crystals(MSCs)exhibit superior carrier transport ability,high specific surface area,shortened photo-carrier diffusion lengths to interfaces and enhanced absorbance of the incident sunlight.These advanced features make metal oxide MCs and MSCs be a promising candidate material in photocatalysis,photoelectrocatalysis,dye sensitized solar cells(DSSCs)and perovskite solar cells(PSCs).Recently,remarkable advances of applying metal oxide MCs and MSCs in these areas have been achieved.Therefore,it is extremely important to deeply understand the influence of the unique properties of metal oxide MCs and MSCs on solar energy conversion systems.Herein,we presented a brief introduction on the synthesis and carrier transfer behavior of metal oxide MCs and MSCs.Then,the rational structure design and modification of metal oxide MCs and MSCs for photocatalysis,photoelectrocatalysis,DSSCs and PSCs are systematically discussed.Finally,the perspectives on extending the application of metal oxide MCs and MSCs are addressed.
基金financial support from Ministry of Science and Technology of the People’s Republic of China(No.2016YFE0112200)the National Natural Science Foundation of China(Nos.21507011,21677037,21607027)
文摘Converting solar energy into valuable hydrogen and hydrocarbon fuels through photoelectrocatalytic water splitting and CO2 reduction is highly promising in addressing the growing demand for renewable and clean energy resources. However, the solar-to-fuel conversion efficiency is still very low due to limited light absorption and rapid bulk recombination of charge carriers. In this work, we present chlorophyll （Chl） and its derivative sodium copper chlorophyllin （ChlCuNa）, as dye sensitizers, modified BiVO4 to improve the photoelectrochemical （PEC） performance. The photocurrent of BiVO4 is surprisingly decreased after a direct sensitization of Chl while the sensitization of ChlCuNa obviously enhances photocurrent of BiV04 electrodes by improved surface hydrophilicity and extended light absorption. ChlCuNa-sensitized BiVO4 achieves an improved H2 evolution rate of 5.43/~molh l cm 2 in water splitting and an enhanced HCOOH production rate 0f2.15 p^mol h 1 cm 2 in CO2 PEC reduction, which are 1.9 times and 2.4 times higher than pristine BiV04, respectively. It is suggested that the derivative ChlCuNa is a more effective sensitizer for solar-to-fuel energy conversion and CO2 utilization than Chl.
文摘Photoelectric property of polyaniline doped with dodecyl-benzene sulphonic acid (DBSA) is studied. The result shows that the concentration of carrier increases obviously, when polyaniline doped with DBSA is irradiated with light. Mixture of sensitive material is advantageous to the absorption of polyaniline in visible light spectrum, and the conductivity is also improved. The results of dielectric measurements on polyaniline doped with DBSA in an Al-PAn-DBSA-Al configuration as function of frequency and temperature are reported. The space-charge polarization phenomenon is observed. Carrier lifetime is microsecond magnitude and mobility is (0.001～0.1) cm 2/V·s, which are obtained by calculation or experiment. The active energy is obtained from the relation between conductivity and temperature. The conducting mechanism of PAn-DBSA is analyzed.
文摘To sensitize polyaniline with dyes by electrochemical polymerization, HClO 4 is employed as the dopant and oxidant, and the polyaniline with different sensitive properties is synthesized. The effect of sensitized emeraldine salt on the absorption spectrum is discussed in details. The maximum conductivity of sensitized films reaches 1.22 S/cm, and investigation on dye sensitizing of the polymer reveals that C.I. Direct Blue 71, C.I. Direct Blue 84, C.I. Direct Black 19 and CuPc-(COOH) 4 may enhance the photoconductivity of polyaniline greatly.
基金This work was financially supported by the National Natural Science Foundation of China (No.10274017)the Natural Science Foundation of Hebei Province, China (No.103097, E2005000131)
文摘The photoelectron property is directly related to the light-energy conversion efficiency of solar cells. In this paper, the photoelectron dynamic of semiconductor was analyzed. The diffusion of electrons has influence on the dielectric function of the solar cell material. And the amplitude variance of the imaginary and real part of the dielectric function is in direct proportion to the dynamic process of free and shallow-trapped electrons. Based on the untouched detection technique, the method is present to detect the amplitude change of the microwave signal which is passing through the material whose dielectric function changes after exposure. A 35 GHz oscillator was used as a microwave source. The absorption and dispersion microwave signals, which contain the dynamic information of free and shallow-trapped electron signal, are split respectively with phase-sensitive instrument. The photoelectron character of n-type Si(100) thin film was investigated by the novel equipment, and the lifetime of different kinds of electrons with the resolution of 1 ns was obtained. The equipment can be directly used in the study of the optoelectronic conversion mechanism of solar cells.
基金Project 59573009 is supported by the National Natural Science Foundation of China.
文摘The photoinitiating system composed of 1-ethyl-3'-methylthiacyanine bro-mide (C-I), 2-chlorohexaarylbiimidazole (o-Cl-HABI) and 3-mercapto-4-methyl-4H-1, 2, 4-triazole (MTA), which act as sensitizer, initiator and hydrogen-donor respectively, can beused to initiate the polymerization of methyl methacrylate (MMA). The kinetic study wascarried out in trichloromathane solution at 30℃ by using dilatometry. The relation be-tween the polymerization rate and the concentrations of C-I, o-Cl-HABI, MTA and MMAwas studied.
基金This work supported by the National Natural Science Foundation of China （No.10647006）, the Promineat Youth Foundation （No.Q200704）, and the Scientific Developmental Foundation of Lanzhou University of Technology. Zi-jiang Liu would like to appreciate the Key Project of Chinese Minsitry of Education （No.209127）. Cai-rong Zhang would like to thank professor Wan-zhen Liang （USTC）, and the Gansu Supercomputer Center is also appreciated.
文摘The geometries, electronic structures, polarizabilities and hyperpolarizabilities, as well as the UV-Vis spectra of the two organic dye sensitizers containing bis-dimethylfluorenyl amino benzofuran were studied via density functional theory （DFT） and time-dependent DFT. The features of electronic absorption spectra were assigned on account of the agreement between the experiment and the calculations. The absorption bands in visible region are related to photoinduced electron transfer processes, and the dimethylfluorenyl amino benzo[b]furan groups are major chromophore that contributed to the sensitization of photo-to-current conversion. The role of vinylene group in geometry, electronic structure and spectra property is analyzed according to the comparative study of the dyes.
