In this paper,bottom contact organic thin-film transistor(OTFT)gas sensors were prepared.Silicon dioxide(SiO2)and titanium/aurum(Ti/Au)were used as the insulating layer and the electrode for the device,respectively.Th...In this paper,bottom contact organic thin-film transistor(OTFT)gas sensors were prepared.Silicon dioxide(SiO2)and titanium/aurum(Ti/Au)were used as the insulating layer and the electrode for the device,respectively.The multi-walled carbon nanotubes(MWCNTs)/α-sexithiophene(α-6T)bilayer films were used as the active layer,andα-6T single layer sensitive film was also prepared for comparison purpose.The electrical and trace NO2-sening properties of these two OTFT gas sensors were tested and analyzed.The results showed that,the OTFT device based on MWCNTs/α-6T bilayer had obviously better electrical properties,better stabilities and higher NO2-sening response values than the device withα-6T single layer,in which both the carrier mobility(μ)and on/off current ratio enhanced two order of magnitude.The improved performance of bilayer OTFT can be explained that MWCNTs acted as highly conducting bridges connecting the crystalline terraces in theα-6T film.Threshold voltage(VT),carrier mobility,on/off current ratio and grid current which showed extremely similar variation trend as source-drain current,were optional parameters to reveal the gas-sensing characteristic of OTFT gas sensors.Morphology analysis showed that the special feature of MWCNTs had certain influence on the gas-sensing properties.展开更多
Organic thin film transistors(OTFTs) based on poly(3-hexylthiophene)(P3HT)/Zinc oxide(ZnO) nanorods composite films as the active layers were prepared by spray-coating process. The OTFTs with P3HT/ZnO-nanorods composi...Organic thin film transistors(OTFTs) based on poly(3-hexylthiophene)(P3HT)/Zinc oxide(ZnO) nanorods composite films as the active layers were prepared by spray-coating process. The OTFTs with P3HT/ZnO-nanorods composite films owned higher carriers mobility than the OTFT based on pure P3 HT. It can be found that the mobility of OTFTs increased by 135% due to ZnO-nanorods doping. This was attributed to the improvement of the P3 HT crystallinity and the optimization of polymer chains orientation. Meanwhile, because of the distinction of work function between P3 HT and ZnO, the majority carriers would accumulate on either side of the P3HT-ZnO interface which benefited carrier transfer. The influence on the mobility of composite film was studied. In addition, the threshold voltage of devices changed positively with the increase of ZnO-nanorods due to the decrease of electrostatic potential for P3HT/ZnO-nanorods composite films. The effect could be explained by the energy level theory of semiconductor.展开更多
基金supported by the Natural Natural Science Foundation of China(Grant Nos.61176066,61101031)
文摘In this paper,bottom contact organic thin-film transistor(OTFT)gas sensors were prepared.Silicon dioxide(SiO2)and titanium/aurum(Ti/Au)were used as the insulating layer and the electrode for the device,respectively.The multi-walled carbon nanotubes(MWCNTs)/α-sexithiophene(α-6T)bilayer films were used as the active layer,andα-6T single layer sensitive film was also prepared for comparison purpose.The electrical and trace NO2-sening properties of these two OTFT gas sensors were tested and analyzed.The results showed that,the OTFT device based on MWCNTs/α-6T bilayer had obviously better electrical properties,better stabilities and higher NO2-sening response values than the device withα-6T single layer,in which both the carrier mobility(μ)and on/off current ratio enhanced two order of magnitude.The improved performance of bilayer OTFT can be explained that MWCNTs acted as highly conducting bridges connecting the crystalline terraces in theα-6T film.Threshold voltage(VT),carrier mobility,on/off current ratio and grid current which showed extremely similar variation trend as source-drain current,were optional parameters to reveal the gas-sensing characteristic of OTFT gas sensors.Morphology analysis showed that the special feature of MWCNTs had certain influence on the gas-sensing properties.
基金supported by the National Natural Science Foundation of China (61471126)a grant from Science and Technology Commission of Shanghai Municipality (16JC1400603)
基金supported by the foundation for Innovation Research Groups of the National Natural Science Foundation of China(NSFC)(Grant No.61421002)the National Natural Science Foundation of China(Grant Nos.61571097)
文摘Organic thin film transistors(OTFTs) based on poly(3-hexylthiophene)(P3HT)/Zinc oxide(ZnO) nanorods composite films as the active layers were prepared by spray-coating process. The OTFTs with P3HT/ZnO-nanorods composite films owned higher carriers mobility than the OTFT based on pure P3 HT. It can be found that the mobility of OTFTs increased by 135% due to ZnO-nanorods doping. This was attributed to the improvement of the P3 HT crystallinity and the optimization of polymer chains orientation. Meanwhile, because of the distinction of work function between P3 HT and ZnO, the majority carriers would accumulate on either side of the P3HT-ZnO interface which benefited carrier transfer. The influence on the mobility of composite film was studied. In addition, the threshold voltage of devices changed positively with the increase of ZnO-nanorods due to the decrease of electrostatic potential for P3HT/ZnO-nanorods composite films. The effect could be explained by the energy level theory of semiconductor.
