Synthesis of Semicenductor Quantum Dots Phosphors and Their Application for the Elecnoluminescence Devices

1.量子点的合成成功地合成了尺寸为~5 nm的CuInS_2量子点。CuInS_2量子点的晶体结构，无论是黄铜矿类型的还是纤锌矿类型的，都与胺的用量和胺加入后的存放时间有关。得到的黄铜矿型和纤锌矿型CuInS_2量子点的光吸收边为~710 nm。对于黄铜矿型CuInS_2，在930 nm处观察到光致发光，而对于纤锌矿型CuInS_2，没有观察到光致发光带。黄铜矿型量子点的光致发光带归因于通过缺陷狂欢的电子-空穴复合。通过对起始溶液的进一步研究，通过控制反应时间，成功地合成了尺寸为1.5~3 nm的黄铜矿型CuInS_2量子点。对于CuInSe_2量子点，在2 0 0~30 0℃的油胺溶液中退火后，发光强度增加，发光波长蓝移。荧光性质的变化与QDS结晶度的增加有关。通过在CuInS_2量子点表面涂覆一层硫化锌薄层，使其在光吸收边附近出现了新的发光带。该发光带可能归因于激子复合。在本实验中，所使用的量子点的大小为~5 nm。当在尺寸为2~3 nm的量子点表面覆盖硫化锌时，可以实现蓝色发光。量子点薄膜及电致发光器件的制备以ZnS-CuInS_2合金化的量子点碰撞溶液为起始溶液，采用电喷射法在玻璃衬底上成功地制备了具有显著发光特性的量子点薄膜。我们还制备了玻璃/ITO/Al_2O_3/量子点薄膜/Al_2O_3/Al等多层EL器件结构。然而，我们没有观察到来自该设备的任何电致发光。

1. Synthesis of quantum dots (QDs)CuInS_2 quantum dots with 〜5nm in size were successfully synthesized. The crystal structure of the CuInS_2 QDs, the chalcopyrite-type or the wurtzite-type, was dependent on the amount of the amines and the storage time after addition of amines. The optical absorption edges of the chalcopyrite- and wurtzite-types CuInS_2 QDs obtained were 〜710nm in wavelength. For the chalcopyrite-type CuInS_2, photoluminescence (PL) band at 930nm was observed, and no PL band was observed for the wurtzite-type CuInS_2. The PL band observed for the chalcopyrite-type QDs was attributed to the electron-hole recombination via defect revels. As a result of the further study of the starting solution, we successfully synthesized chalcopyrite-type CuInS_2 QDs with 1.5〜3nm sizes by controlling of the reaction time. For the CuInSe_2 QDs, the increase in PL intensity and the blue shift of the PL wavelength were observed by annealing in oleylamine at 200〜300℃. The changes in the PL properties were related to the increase in the crystallinity of the QDs.2. Improving the PL propertiesThe PL band near optical absorption edge was newly appeared by overcoating of the CuInS_2 QDs by ZnS thin layer. The PL band may be attributable to the exciton recombination. In this experiment, the QDs used was 〜5nm in size. When the QDs with 2〜3nm in size are overcoated by ZnS, the blue PL may be realized.3. Fabrication of the QDs thin films and electroluminescence devicesBy using the ZnS-CuInS_2 alloyed QDs collidal solution as a starting solution, the QDs thin film on the glass substrate, which showed significant PL, was successfully fabricated by electro-spraying. We also fabricated the multilayered EL-device structure, such as glass/ITO/Al_2O_3/QDs-film/Al_2O_3/Al. However, we could not observe any electroluminescence from the device.