Organic Electrical Bistable Devices Based On Tris(2-phenylpyridine)iridium(?)

Organic electrical bistable devices have currently emerged as promising candidates for next-generation memory devices due to their unique advantages such as light weight,low power consumption,simple-fabrication process and potential applications in flexible and large-area devices.In this work,the commercialized tris(2-phenylpyridine)iridium(?)(Ir(ppy)3),which acts as the trapping center,is first used in the organic bistable devices based on poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene](MEH-PPV)or polymethyl methacrylate(PMMA)via a simple spin-coating method.In the first part,the electrical bistable devices based on MEH-PPV/Ir(ppy)3 were studied.The MEH-PPV concentration effect on the device performance has been investigated.When the concentration of MEH-PPV is 4 mg/mL,the device yields the optimal electrical ON/OFF ratio up to 1×103.The operating mechanism of devices was analyzed by fitted I-V curves.Then the current-repeatable times(I-times)measurements were taken to investigate the performance of the devices.The results show that the current transition process is attributed to the formation and deformation of the interface dipole layer under different voltage biases.In the second part,Ir(ppy)3 was used to fabricate organic electrical bistable devices based on PMMA conductive layer via a simple spin-coating method.The obtained devices exhibit the typical electrical bistable property,and the optimal ON/OFF ratio is up to 103.Then the current-repeatable times(I-times)measurements were taken to investigate the performance of the devices.The write-read-erase-read parameter measurements were taken to investigate the devices have the stable performance under operating condition.The charge trapping-detrapping theory is used to explain the operating mechanism of bilayer device on the basis of fitted I-V curves.