The trapped carriers lead to the rise of the internal electrical field at the Ag2S/PVK interface, which can change the conductivity of the device. All the results of the theoretical fitting are consistent with the charge trapping mechanism. Conclusions In summary, organic bistable FK228 order devices based on Ag2S-PVK composites
were fabricated by a simple spin-coating method. Obvious electrical bistability and NDR effects have been observed in the devices due to the existence of the Ag2S nanospheres. The NDR effects can be controlled by varying the charging voltages and charging time. The maximum ON/OFF current ratio can reach up to 104. The carrier transport can be described in terms of the organic electronic models, and the carrier transport mechanism alters from the thermionic
emission to the ohmic model during the transition from OFF state to ON state, which is closely associated with Thiazovivin in vivo the charge trapping/detrapping process in the Ag2S-PVK composites. Acknowledgements This work was partly supported by the National Science Foundation for Distinguished Young Scholars of China BAY 80-6946 ic50 (No. 61125505), the National Natural Science Foundation of China (Grant No. 61108063), and the author (A. W) is also grateful to the financial support from Beijing JiaoTong University (2012RC046). References 1. Yang Y, Ouyang J, Ma L, Tseng RJH, Chu CW: Electrical switching and bistability in organic/polymeric Tyrosine-protein kinase BLK thin films and memory devices. Adv Funct Mater 2006, 16:1001.CrossRef 2. Mukherjee B, Mukherjee M: Nonvolatile
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