Three methods for synthesis of benzotellurazole crown ether(6)are described.The cyanine dye(8)can be easily obtained by treating(6) with CH_3I and CH(OEt)_3.
Photoinduced spectral change can be utilized for various optical devices. The photoinduced spectral change due to an organic dye was demonstrated for the organic-inorganic hybrid film without the aid of photochromism ...Photoinduced spectral change can be utilized for various optical devices. The photoinduced spectral change due to an organic dye was demonstrated for the organic-inorganic hybrid film without the aid of photochromism with a simple preparation method for the first time. By the hybridization of a cyanine dye of 2-[5-(1,3-dihydro-3,3-dimethyl-1-octadecyl-2H-indol-2-ylidene)-1,3-pentadienyl]-3,3-dimethyl-1-octadecyl-3H-indolium perchlorate (NK3175) with an inorganic layered material of cation-exchangeable clay, smectite (SWN), a spectral change attributed to NK3175 was generated upon the irradiation of UV light. This result might serve as useful information on the methodology to produce optically controlled function for photoresponsive systems. Furthermore, the hybrid film of SWN and NK3175 was characterized by the use of XRD and FT-IR measurements. NK3175 molecules adsorbed onto external surfaces of SWN were confined by oriented SWN. It was suggested that the enhanced intermolecular interaction between NK3175 molecules caused by the hybridization with SWN resulted in the change of the aggregation state of NK3175 upon the UV light irradiation, which accounts for the spectral change of NK3175.展开更多
A low cost cyanine dye, 1,1-dimethyl-3-ethyl-2-[3-(1,3-dihydro-3,3-dimethyl-1-ethyl- 5-carboxyl-2H-indol-2-ylidene)-1-propenyl]-1H-benz[e] indolium iodide (1) was synthesized and applied to sensitize mesoporous TiO2 e...A low cost cyanine dye, 1,1-dimethyl-3-ethyl-2-[3-(1,3-dihydro-3,3-dimethyl-1-ethyl- 5-carboxyl-2H-indol-2-ylidene)-1-propenyl]-1H-benz[e] indolium iodide (1) was synthesized and applied to sensitize mesoporous TiO2 electrode. Photoresponse of the electrode was extended to the visible and remarkably high incident photon-to-current conversion efficiency (IPCE) over 70% was achieved from 500 nm to 600 nm.展开更多
Various methods for synthesis of 2-methyl-5,6-(1,4, 7,10,13-pentaoxatridecamethylene)benzotellurazole (8) are described. Under different conditions, alkylation of compound 8 with methyl iodide gave telluronium salt 1,...Various methods for synthesis of 2-methyl-5,6-(1,4, 7,10,13-pentaoxatridecamethylene)benzotellurazole (8) are described. Under different conditions, alkylation of compound 8 with methyl iodide gave telluronium salt 1,2-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzotellurazolium iodide (15) or quaternary ammonium salt 2,3-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzotellurazolium iodide (14) in high yields, repectively. The cyanine dye 3,3'-dimethyl-5,6,5',6'-bis(1,4,7,10,13-pentaoxatridecamethylene)telluracarbocyanine iodide (16) is obtained by condensation of 14 with ethyl orthoformate in acetic anhydride, The visible absorption of the cyanine dye is also discussed.展开更多
Two infrared dyes, 1,3,3,1′, 3′, 3′ hexamethylindotricarbocyanine iodide (A) and 1,3,3,1′,3′,3′ hexamethyl 11 chloro 10,12 propylenetricarbocyanine iodide (B), were synthesized and characterized by melting...Two infrared dyes, 1,3,3,1′, 3′, 3′ hexamethylindotricarbocyanine iodide (A) and 1,3,3,1′,3′,3′ hexamethyl 11 chloro 10,12 propylenetricarbocyanine iodide (B), were synthesized and characterized by melting point, elemental analysis, IR, and 1 H NMR. Their electron absorption spectra, laser absorption characteristics and solubility were investigated. The results showed that A and B have maximum absorption peaks at around 748nm and 774nm, respectivey, which match well with the wavelength output of the near infrared laser diode. The dyes were found to have photoinduced fading during irradiation with the infrared laser, especially in the presence of oxygen. However, this procession can be greatly slowed by using a layer of poly(vinyl alcohol) to barricade the dyes from oxygen. The experiments also showed that the dyes were thermally stable but decayed under strong sunlight. Furthermore, they are easily dissolved in some common solvents.展开更多
Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcinat...Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcination of titanyl hydroxide. These TiO2 nano powders were used to fabricate photoelectrodes for the dye-sensitized solar cell （DSSC） and their performance was compared to that of the DSSC fabricated with Degussa P25 TiO2. The results showed that the SCS TiO2 could work well as photoelectrode for DSSC. The SCS TiO2 contained impurities of C and/or S, thus exhibiting visible light absorption and reduced band gap. The open circuit voltage and the fill factor both varied little among the various TiO2 and thus both had little effect on the photoelectrical conversion efficiency （η）. However, the variation of r/was seen to be in quite a good agreement with that of the short circuit current （Isc）, suggesting that r/was dominated by Isc. lsc was found to be enhanced by light scattering effect due to the presence of large particles but reduced by high impurity content due to an increase in electron transfer resistance. In addition, the specific surface area of the powders was found to be an important factor affecting the Isc and thus the η.展开更多
Long and well-aligned ZnO nanowires were hydrothermally synthesized on FTO glass based on a ZnO seed layer which was prepared by spin-coating and annealing techniques.The effect of the growth solution refreshment on t...Long and well-aligned ZnO nanowires were hydrothermally synthesized on FTO glass based on a ZnO seed layer which was prepared by spin-coating and annealing techniques.The effect of the growth solution refreshment on the morphology of ZnO nanowires was investigated and the possible mechanism was discussed.After refreshing the growth solution for 5 cycles,ZnO nanowires of ~ 120 nm in diameter and ~ 20 /μm in length were obtained.The prepared ZnO nanowires were used as photoelectrodes in dye-sensitized solar cells（DSSCs）,showing excellent photovoltaic performance.With the increase of growth cycles of ZnO nanowires,the photocurrent of DSSCs increased obviously due to the increased dye loading on the surface of ZnO nanowires.The results indicated that the lone and well-aligned ZnO nanowires are promising for DSSCs application.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
文摘Three methods for synthesis of benzotellurazole crown ether(6)are described.The cyanine dye(8)can be easily obtained by treating(6) with CH_3I and CH(OEt)_3.
文摘Photoinduced spectral change can be utilized for various optical devices. The photoinduced spectral change due to an organic dye was demonstrated for the organic-inorganic hybrid film without the aid of photochromism with a simple preparation method for the first time. By the hybridization of a cyanine dye of 2-[5-(1,3-dihydro-3,3-dimethyl-1-octadecyl-2H-indol-2-ylidene)-1,3-pentadienyl]-3,3-dimethyl-1-octadecyl-3H-indolium perchlorate (NK3175) with an inorganic layered material of cation-exchangeable clay, smectite (SWN), a spectral change attributed to NK3175 was generated upon the irradiation of UV light. This result might serve as useful information on the methodology to produce optically controlled function for photoresponsive systems. Furthermore, the hybrid film of SWN and NK3175 was characterized by the use of XRD and FT-IR measurements. NK3175 molecules adsorbed onto external surfaces of SWN were confined by oriented SWN. It was suggested that the enhanced intermolecular interaction between NK3175 molecules caused by the hybridization with SWN resulted in the change of the aggregation state of NK3175 upon the UV light irradiation, which accounts for the spectral change of NK3175.
文摘A low cost cyanine dye, 1,1-dimethyl-3-ethyl-2-[3-(1,3-dihydro-3,3-dimethyl-1-ethyl- 5-carboxyl-2H-indol-2-ylidene)-1-propenyl]-1H-benz[e] indolium iodide (1) was synthesized and applied to sensitize mesoporous TiO2 electrode. Photoresponse of the electrode was extended to the visible and remarkably high incident photon-to-current conversion efficiency (IPCE) over 70% was achieved from 500 nm to 600 nm.
基金Project supported by a doctoral special grant from the State of Education Commission and the National Natural Science Foundation of China.
文摘Various methods for synthesis of 2-methyl-5,6-(1,4, 7,10,13-pentaoxatridecamethylene)benzotellurazole (8) are described. Under different conditions, alkylation of compound 8 with methyl iodide gave telluronium salt 1,2-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzotellurazolium iodide (15) or quaternary ammonium salt 2,3-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzotellurazolium iodide (14) in high yields, repectively. The cyanine dye 3,3'-dimethyl-5,6,5',6'-bis(1,4,7,10,13-pentaoxatridecamethylene)telluracarbocyanine iodide (16) is obtained by condensation of 14 with ethyl orthoformate in acetic anhydride, The visible absorption of the cyanine dye is also discussed.
文摘Two infrared dyes, 1,3,3,1′, 3′, 3′ hexamethylindotricarbocyanine iodide (A) and 1,3,3,1′,3′,3′ hexamethyl 11 chloro 10,12 propylenetricarbocyanine iodide (B), were synthesized and characterized by melting point, elemental analysis, IR, and 1 H NMR. Their electron absorption spectra, laser absorption characteristics and solubility were investigated. The results showed that A and B have maximum absorption peaks at around 748nm and 774nm, respectivey, which match well with the wavelength output of the near infrared laser diode. The dyes were found to have photoinduced fading during irradiation with the infrared laser, especially in the presence of oxygen. However, this procession can be greatly slowed by using a layer of poly(vinyl alcohol) to barricade the dyes from oxygen. The experiments also showed that the dyes were thermally stable but decayed under strong sunlight. Furthermore, they are easily dissolved in some common solvents.
基金Support of this research by the National Science Council of Taiwan under Grant No. NSC 100-2221-E-006-214partial support under Contract No. 101-D0204-6 by the Bureau of Energy, Ministry of Economic Affairs of Taiwanthe LED Lighting Research Center, NCKU
文摘Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcination of titanyl hydroxide. These TiO2 nano powders were used to fabricate photoelectrodes for the dye-sensitized solar cell （DSSC） and their performance was compared to that of the DSSC fabricated with Degussa P25 TiO2. The results showed that the SCS TiO2 could work well as photoelectrode for DSSC. The SCS TiO2 contained impurities of C and/or S, thus exhibiting visible light absorption and reduced band gap. The open circuit voltage and the fill factor both varied little among the various TiO2 and thus both had little effect on the photoelectrical conversion efficiency （η）. However, the variation of r/was seen to be in quite a good agreement with that of the short circuit current （Isc）, suggesting that r/was dominated by Isc. lsc was found to be enhanced by light scattering effect due to the presence of large particles but reduced by high impurity content due to an increase in electron transfer resistance. In addition, the specific surface area of the powders was found to be an important factor affecting the Isc and thus the η.
基金Project supported by the State Key Development Program for Basic Research of China(Nos.2011CB302101,2011CB302105)
文摘Long and well-aligned ZnO nanowires were hydrothermally synthesized on FTO glass based on a ZnO seed layer which was prepared by spin-coating and annealing techniques.The effect of the growth solution refreshment on the morphology of ZnO nanowires was investigated and the possible mechanism was discussed.After refreshing the growth solution for 5 cycles,ZnO nanowires of ~ 120 nm in diameter and ~ 20 /μm in length were obtained.The prepared ZnO nanowires were used as photoelectrodes in dye-sensitized solar cells（DSSCs）,showing excellent photovoltaic performance.With the increase of growth cycles of ZnO nanowires,the photocurrent of DSSCs increased obviously due to the increased dye loading on the surface of ZnO nanowires.The results indicated that the lone and well-aligned ZnO nanowires are promising for DSSCs application.
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.
