Optofluidics is the integration of optics and microfluidics(so-called lab on the chip). Wherein the actuation of liquid is a key technic. In a variety of methods for controlling microscale liquid, the light actuation ...Optofluidics is the integration of optics and microfluidics(so-called lab on the chip). Wherein the actuation of liquid is a key technic. In a variety of methods for controlling microscale liquid, the light actuation is particularly interesting. The light actuation offers a novel way to control the flow of fluids for biomedical and biotechnological applications, etc.. The complexity and cost of devices sometimes may be greatly reduced by using complete optical control and may be more flexible in operation than other methods. However the light actuation of liquid is a burgeoning field as well as optofluidics. There is lots of work to do. Here we systematically describe four mechanisms for the light actuation of liquid based on the following points: optoelectrowetting, photothermal effect, radiation pressure, photosensitive substance.展开更多
White organic light-emitting diodes were fabricated by using a novel phosphorescence bis(1,2-diphenyl-1H-benzoimidazole)iridium(acetylacetonate)[(pbi)2Ir(acac)] as sensitizer and a fluorescent dye of 4- (dicy...White organic light-emitting diodes were fabricated by using a novel phosphorescence bis(1,2-diphenyl-1H-benzoimidazole)iridium(acetylacetonate)[(pbi)2Ir(acac)] as sensitizer and a fluorescent dye of 4- (dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) codoped into a carbazole polymer of poly(N-vinylcarbazole) (PVK). Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of (pbi)2Ir(acac) and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of (pbi)2Ir(acac) and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the guests enabled a strong yellow emission from (pbi)2Ir(acac) and DCJTB, where (pbi)2Ir(acac) plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N'-diphenyl-N,N'-bis(1- naphthyl)(1,1'-biphenyl)-4,4'-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1'Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.展开更多
基金Fund of Nanjing University of Posts & Telecommunications(NY206076)
文摘Optofluidics is the integration of optics and microfluidics(so-called lab on the chip). Wherein the actuation of liquid is a key technic. In a variety of methods for controlling microscale liquid, the light actuation is particularly interesting. The light actuation offers a novel way to control the flow of fluids for biomedical and biotechnological applications, etc.. The complexity and cost of devices sometimes may be greatly reduced by using complete optical control and may be more flexible in operation than other methods. However the light actuation of liquid is a burgeoning field as well as optofluidics. There is lots of work to do. Here we systematically describe four mechanisms for the light actuation of liquid based on the following points: optoelectrowetting, photothermal effect, radiation pressure, photosensitive substance.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.60425101), the Program for the New Century Excellent Talents in University of Ministry of Education of China (No.NCET-06-0812), and the Young Talent Project of University of Electronic Science and Technology of China (No.060206).
文摘White organic light-emitting diodes were fabricated by using a novel phosphorescence bis(1,2-diphenyl-1H-benzoimidazole)iridium(acetylacetonate)[(pbi)2Ir(acac)] as sensitizer and a fluorescent dye of 4- (dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) codoped into a carbazole polymer of poly(N-vinylcarbazole) (PVK). Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of (pbi)2Ir(acac) and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of (pbi)2Ir(acac) and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the guests enabled a strong yellow emission from (pbi)2Ir(acac) and DCJTB, where (pbi)2Ir(acac) plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N'-diphenyl-N,N'-bis(1- naphthyl)(1,1'-biphenyl)-4,4'-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1'Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.