The Study Of Iridium Complexes With C^N Ligand Functionalization In Memory Devices

With the rapid development of the information industry, there is a growing demand for exploiting new-generation data-storage technologies. Conventional Si/Ge-based technologies, which are common in the information storage field, are facing the theoretical and physical limits of downscaling. Due to the advantages of good scalability, flexibility, low cost, ease of processing, 3D-stacking capability, and large capacity for data storage, organic bistable memory has attracted significant scientific interest as a new and promising research field. At the same time, although transition metal iridium complexes are widely studied and applied in organic light-emitting diodes, solar cell, cell imaging etc. Due to their excellent optoelectronic properties, the reports about their application in memory devices are very few. However, their use in the storage is full of infinite possibilities with their own excellent charge transport and redox properties.In this thesis, we designed and synthesized a series of iridium complexes containing different main group elements. By adjusting the substituent, memory properties with Flash and WORM effect have been realized. Through ultraviolet-visible absorption spectra(UV-Vis), emission was studied. Memory devices with ITO/small molecule/Al sandwiched structure were prepared by storage devices, and then the I-V curve, retention time and cycling endurance were tested to determine the memory performance and effect. Later we calculated by theoretical calculation(DFT) distribution of HOMO and LUMO orbit and molecular electrostatic potential(ESP). Then, the morphology of active layer of thin film has been observed by atomic force microscopy(AFM), through the analyses of data, the storage mechanism is studied and discussed.Due to the redox and charge transfer characteristics of ferrocene, the photophysical and electrochemical properties of the device can be enriched through grafting it onto the iridium complexes, thus the Flash storage feature has been realized. Memory devices with ITO/small molecule/Al sandwiched structure were prepared by storage devices, and then the I-V curve and retention time and cycling endurance were tested to determine the storage performance and effect. Finally, calculated by the theory of the HOMO and LUMO energy levels and observed atomic force microscope images, data have been compared and the effect and mechanism of memory devices have been investigated.In the research work of this thesis, a series of iridium complexes are applied in electrical storage devices, and show the better performance of devices, such as low threshold voltage, large ON/OFF current ratio, long retention time and good stabilization and so on. It not only expand the storage materials based on iridium complexes in the application of electronic storage devices, also provides a new train of thought for the future design and synthesis of new organic small molecular materials for electronic storage device.