以溶液法合成 FeS2 奈米晶體並應用於近紅外光偵測器
Abstract
本實驗係以二硫化鐵奈米晶體 (FeS2 NCs) 作為近紅外光偵測器的主動層，並以氧化锌 (ZnO) 作為元件 blocking layer 之研究。二硫化鐵為非直接能隙半導體，擁有較窄的半導體能隙 (0.95 eV) ，且對光有很強的吸收，吸收範圍可以到近紅外光波段，之所以使用二硫化鐵奈米晶體的原因是因為材料合成容易、價錢低廉且是由對環境無害的元素組成。本實驗的二硫化鐵奈米晶體是利用溶液法合成，並可以進一步地藉由調控表面活性劑和溶劑比例來控制二硫化鐵奈米晶體的形狀以及在溶液中的分散性，接著藉由 XRD 和 TEM 可以分析其晶格和構型。而經由元件所量測的 J-V characteristics 及 temporal photocurrent response 得知，以二硫化鐵奈米晶體作為光偵測器之元件，確實在可見光及近紅外光波段 (波長 > 715 nm) 皆有光電流產生。
In this thesis, the near infrared photodetectors based on FeS2 nanocrystals were studied. We used FeS2 nanocrystals as the active layer and ZnO as blocking layer for the devices. FeS2 is a indirect band gap semiconductor which has a narrow band gap of 0.95 eV with high absorption to the light even near-infrared range, and the advantage in using the FeS2 nanocrystals is because they are low-cost, abundant and non-toxic materials. The well dispersed FeS2 nanocrystals were synthesis by Solution –phase methods, furthermore, we could control the shapes of FeS2 nanocrystals by adjust the ratio of surfactant to solvent, then the crystal morphology and structure were identified by TEM and XRD. In conclusion, the photodetectors based on FeS2 nanocrystals response in both the visible and infrared ( λ > 715 nm) have been demonstrated by Current density–voltage characteristics and temporal photocurrent response of the devices.
In this thesis, the near infrared photodetectors based on FeS2 nanocrystals were studied. We used FeS2 nanocrystals as the active layer and ZnO as blocking layer for the devices. FeS2 is a indirect band gap semiconductor which has a narrow band gap of 0.95 eV with high absorption to the light even near-infrared range, and the advantage in using the FeS2 nanocrystals is because they are low-cost, abundant and non-toxic materials. The well dispersed FeS2 nanocrystals were synthesis by Solution –phase methods, furthermore, we could control the shapes of FeS2 nanocrystals by adjust the ratio of surfactant to solvent, then the crystal morphology and structure were identified by TEM and XRD. In conclusion, the photodetectors based on FeS2 nanocrystals response in both the visible and infrared ( λ > 715 nm) have been demonstrated by Current density–voltage characteristics and temporal photocurrent response of the devices.
Description
Keywords
紅外光偵測器