An electron transporting material of TFTTP （4-（5-hexylthiophene-2-yl）-2,6-bis（5-trifluoromethyl）thiophen-2-yl）pyridine） was investigated as a cathode buffer layer to enhance the power efficiency of organic sola...An electron transporting material of TFTTP （4-（5-hexylthiophene-2-yl）-2,6-bis（5-trifluoromethyl）thiophen-2-yl）pyridine） was investigated as a cathode buffer layer to enhance the power efficiency of organic solar cells （OSCs） based on subphthalocyanine and C60. The overall power conversion efficiency was increased by a factor of 1.31 by inserting the TFTTP interfacial layer between the active layer and metallic cathode. The inner mechanism responsible for the performance enhancement of OSCs was systematically studied with the simulation of dark diode behavior and optical field distribution inside the devices as well as the characterization of device photocurrent. The results showed that the TFTTP layer could significantly increase the built-in potential in the devices, leading to the enhanced dissociation of charge transfer excitons. In addition, by using TFTTP as the buffer layer, a better Ohmic contact at C60/metal interface was formed, facilitating more efficient free charge carrier collection.展开更多
Organic solar cells with inverted planar heterojunction structure based on subphthalocya- nine and C60 were fabricated using several kinds of materials as cathode buffer layer （CBL）, including tris-8-hydroxy-quinoli...Organic solar cells with inverted planar heterojunction structure based on subphthalocya- nine and C60 were fabricated using several kinds of materials as cathode buffer layer （CBL）, including tris-8-hydroxy-quinolinato aluminum （Alq3）, bathophenanthroline （Bphen）, bathocuproine, 2,3,8,9,14,15-hexakis-dodecyl-sulfanyl-5,6,11,12,17,18-hexaazatrinaphthylene （HATNA）, and an inorganic compound of Cs2CO3. The influence of the lowest unoccupied molecular orbital level and the electron mobility of organic CBL on the solar cells perfor- mance was compared. The results showed that Alq3, Bphen, and HATNA could significantly improve the device performance. The highest efficiency was obtained from device with an- nealed HATNA as CBL and increased for more than 7 times compared with device without CBL. Furthermore~ the simulation results with space charge-limited current theory indicated that the Schottky barrier at the organic/electrode interface in inverted OSC structure was reduced for 27% by inserting HATNA CBL.展开更多
文摘An electron transporting material of TFTTP （4-（5-hexylthiophene-2-yl）-2,6-bis（5-trifluoromethyl）thiophen-2-yl）pyridine） was investigated as a cathode buffer layer to enhance the power efficiency of organic solar cells （OSCs） based on subphthalocyanine and C60. The overall power conversion efficiency was increased by a factor of 1.31 by inserting the TFTTP interfacial layer between the active layer and metallic cathode. The inner mechanism responsible for the performance enhancement of OSCs was systematically studied with the simulation of dark diode behavior and optical field distribution inside the devices as well as the characterization of device photocurrent. The results showed that the TFTTP layer could significantly increase the built-in potential in the devices, leading to the enhanced dissociation of charge transfer excitons. In addition, by using TFTTP as the buffer layer, a better Ohmic contact at C60/metal interface was formed, facilitating more efficient free charge carrier collection.
文摘Organic solar cells with inverted planar heterojunction structure based on subphthalocya- nine and C60 were fabricated using several kinds of materials as cathode buffer layer （CBL）, including tris-8-hydroxy-quinolinato aluminum （Alq3）, bathophenanthroline （Bphen）, bathocuproine, 2,3,8,9,14,15-hexakis-dodecyl-sulfanyl-5,6,11,12,17,18-hexaazatrinaphthylene （HATNA）, and an inorganic compound of Cs2CO3. The influence of the lowest unoccupied molecular orbital level and the electron mobility of organic CBL on the solar cells perfor- mance was compared. The results showed that Alq3, Bphen, and HATNA could significantly improve the device performance. The highest efficiency was obtained from device with an- nealed HATNA as CBL and increased for more than 7 times compared with device without CBL. Furthermore~ the simulation results with space charge-limited current theory indicated that the Schottky barrier at the organic/electrode interface in inverted OSC structure was reduced for 27% by inserting HATNA CBL.
