利用銀奈米粒子層提升高分子太陽能電池之效率

EFFICIENCY ENHANCEMENT OF POLYMER SOLAR CELLS USING A LAYER OF SILVER NANODISKS

歐珍方(Cheng-Fang Ou)

《技術學刊》 31卷2期 (2016/06) Pp. 85-92

摘要

銀奈米材料具有良好的化學和物理穩定性，銀奈米粒子(silver nanoparticles, Ag NPs)能夠引起局部表面電漿共振效應(localized surface plasmon resonance, LSPR)來提升太陽能電池的光電流。我們將粒徑約為50至80 nm的圓盤形銀奈米粒子(silver nanodisk)添加於ITO (indium tin oxide)層上來提高高分子太陽能電池的性能。本研究之電池結構為ITO/Ag NPs/PEDOT：PSS/P3HT:PC_(61)BM(1:1)/Ca/Al，改變銀奈米粒子在ITO層自組吸附時間分別為20、40、60和80分鐘，因此可得到不同的銀奈米粒子密度分佈。我們利用紫外光-可見光吸收光譜儀(UV-Vis)、掃描探針顯微鏡(SPM)、場發射電子顯微鏡(FE-SEM)和太陽光模擬光源系統來測量吸收度、粗糙度、表面形態和光電性質。由結果知，四種不同銀奈米粒子覆蓋密度之高分子太陽能電池之短路電流密度 (short-circuit current density, J_(sc))、填充因子(fill factor, FF)與光電轉換效率(power conversion efficiency, PCE)皆比未添加之電池高，顯示添加四種不同數量或覆蓋密度銀奈米粒子於ITO層皆能有效提高電池之光電性能。試樣中以反應60分鐘之電池的提升效果最佳，此電池具有最高的J_(sc)與PCE，分別為8.97 mA/cm^2與3.57%，與未添加之電池比較分別提升了26%與60%，而FF也從0.49增加到0.63，提升了29%。此提升結果可能是由於圓 盤形銀奈米粒子產生之局部表面電漿共振效應增加了光電流所致。

關鍵字

高分子太陽能電池 ； 銀奈米粒子 ； 局部表面電漿共振 ； 光電轉換效率

並列摘要

Silver nanoparticles (Ag NPs) exhibit stable chemical and physical properties. We report on the efficiency enhancement of polymer solar cells by incorporating a silver nanoparticles self-assembled layer, grown on the indium tin oxide (ITO) surface by the electrostatic interaction between the silver particles and modified ITO. The structure of polymer solar cells was ITO/Ag NPs/PEDOT:PSS/P3HT:PC_(61)BM(1:1)/Ca/Al. The coverage density of the silver nanodisks on the ITO substrates was controlled by varying the reaction time of 20, 40, 60 and 80 min. We employed UV-Vis, SPM, FE-SEM and solar simulator to measure the absorbance, roughness, surface morphology, and power conversion efficiency (PCE), respectively. From these results, we found that the short circuit density (J_(sc)), fill factor (FF) and PCE of the cells with Ag NPs are always higher than those cells without Ag NPs. The polymer solar cells with Ag NPs by 60 min electrostatic interaction exhibited the highest J_(sc) of 8.97 mA/cm2 and PCE of 3.57%. The increases of J_(sc) and PCE were 26% and 60% when compared to cells without Ag NPs, respectively. The PCE increased mainly from the improved photocurrent density as a result of excited localized surface plasmon resonance (LSPR) induced by silver nanoparticles.

並列關鍵字

polymer solar cell ； silver nanoparticles ； localized surface plasmon resonance ； power conversion efficiency