本研究成功利用微波輔助合成法取代傳統水熱合成法製備氧化鎳奈米顆粒，達到縮短製程時間並減少能源損耗之效益，透過調變微波功率、微波溫度、微波時間及燒結溫度等參數，改變氧化鎳產物之形貌及顆粒大小，成功取代商用氧化鎳顆粒。選出合適參數進行鋰或銅摻雜實驗，增進氧化鎳導電率，經摻雜後，順利提升氧化鎳導電率，將其應用至鈣鈦礦元件系統中，降低整體元件的串聯電阻，改善其填充因子，減少輸出電流的損耗，進而使元件轉換效率增加。
採用未摻雜之微波合成氧化鎳顆粒所製備之元件，其元件表現為開路電壓1.04 V、短路電流密度16.8 mA/cm2、填充因子0.53、轉換效率9.4%；經鋰1 at%摻雜條件處理後，元件表現為開路電壓1.00 V、短路電流密度18.7 mA/cm2、填充因子0.65、轉換效率12.3%，成功提升電流密度與填充因子，進而改善元件效率。

In this study, we prepared nickel oxide (NiO) nanoparticles (NiOnp), Li-doped NiOnp, and Cu-doped NiOnp via microwave-assisted hydrothermal method and applied these NiOnp as hole transport materials (HTMs) for mesoscopic inverted (p-i-n heterojunction) organometallic lead halide perovskite solar cells (PSCs). Their electrical properties were studied when these NiOnp were spin-coated on the glass substrate to form mesoporous layers. The room temperature conductivity of undoped NiOnp mesoporous layer, derived from Hall effect measurements, was 4.6×10-4 S·cm-1. The conductivity of Li 7 at% and Cu 7 at% doped NiOnp films was estimated to be 6.2×10-3 S·cm-1 and 5.7×10-3 S·cm-1, respectively, which is 12~13 times better than that of the undoped reference. The series resistance (Rs) of the PSCs utilizing Li-doped NiOnp or Cu-doped NiOnp decreased with respect to that using undoped NiOnp, leading to a superior fill factor (FF) with a value exceeding 0.72. Accordingly, the fabricated PSC based on Li-doped and Cu-doped NiOnp exhibited an increased power conversion efficiency up to 12.3% and 11.1%, respectively, compared to the undoped NiOnp counterpart with an efficiency of 9.4%.

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