噴射式大氣電漿處理之二氧化鈦於鈣鈦礦太陽能電池之應用

Abstract

本論文研究以噴射式大氣電漿製程處理二氧化鈦薄膜之性質並應用於鈣鈦礦太陽能電池中。二氧化鈦以異丙醇鈦(titanium isopropoxide)為前驅物，以溶膠凝膠法製備；並採旋轉塗佈方式沉積30 nm薄膜，再以氮氣大氣電漿處理之。在1分鐘內，氮氣大氣電漿可快速地去除溶劑並轉換膠體粒子形成非晶二氧化鈦，得到平整且緻密二氧化鈦薄膜；分析電漿放射光譜，可知是藉電漿中N2 1st與2nd positive幫助快速反應所致。透過XRD分析，我們發現經電漿處理所得二氧化鈦屬非晶結構，與高溫退火之銳鈦礦晶相不同。將以氮氣為33 slm，處理時間為40秒之二氧化鈦做電子傳輸層，以一步驟溶液方式旋塗MAPbI3鈣鈦礦(lead methylammonium tri-iodide perovskite)，所製作之太陽能電池具有最佳光電轉換效率14.3%；可以與高溫退火30分鐘二氧化鈦所製作之元件，轉換效率為13.2%相比擬。我們成功採用構造簡單且製程時間快速之大氣電漿裝置製作有效之鈣鈦礦太陽能電池，具應用潛力。

In this thesis, we study the characteristics of atmospheric plasma jet (APPJ) treated titanium dioxide thin film and its applications in perovskite solar cells. Titanium dioxide is prepared by sol-gel method, with titanium isopropoxide as precursor. A 30-nm-thick titanium dioxide (TiO2) precursor thin film is spin coated on a fluorine doped tin oxide substrate, followed by APPJ treatment. In less than one minute, the nitrogen APPJ efficiently removes solvents and convert the gels into amorphous titanium dioxide, and the acquired film is flat and compact, the rapid conversion can be attributed to the highly reactive 1st and 2nd positive of N2 in the plasma. The X-ray diffraction (XRD) pattern implies that the plasma treated TiO2 is amorphous phase, while the furnace annealed one is anatase phase. We further apply the plasma treated TiO2 to MAPbI3 perovskite solar cell as the electron transport layer. By one step solution method, we obtain perovskite solar cell with best energy transfer efficiency of 14.3%, which is similar to solar cells with 30 min annealed titanium dioxide, at 13.2%. The result suggests that ultra-short APPJ-treated TiO2 is promising for perovskite solar cell applications.