異質接面太陽能電池材料-NMFP衍生物之理論計算探討

Theoretical Studies on the Electronic Structures and Photophysical Properties of the N-methyle-3, 4-fulleropyrrolidine Derivatives for the Bulk Heterojunction Solar Cell Material

謝韋毅(Wei Yi, Hsieh)

指導教授 ： 王伯昌

淡江大學/理學院/化學學系碩士班/碩士(2010年)

https://doi.org/10.6846/TKU.2010.00591

摘要

以不同的連結基及不同的推電子基修飾NMFP，設計出不同的電子受體分子，接著利用理論計算的方法分析他們的相關性質，如能隙、光譜…等，研究連結基與推電子基對分子造成的影響，試圖找出具有高LUMO值或低能隙的電子受體，以提升BHJ太陽能電池的光電轉換效率。
結果發現，連結基有助分子形成電荷分離狀態，長度愈長時，HOMO愈高，能隙愈低，但LUMO也下降；S0→S1的躍遷主要發生在HOMO、LUMO間，最大吸收波長有紅位移的現象，且吸收波長範圍分布廣泛。
預期NMFP-L1和NMFP-L3具有比較好的發展潛力，所以選擇此二系列結合不同的推電子基，做進一步分析；NMFP-L1和NMFP-L3與推電子基的結合後，最大吸收波長有紅位移的現象；八個分子中，N-L3-D1的平面性最好；LUMO值最高的是N-L3-D2，能隙值最小的是N-L1-D4，整體數值都不錯的是N-L1-D2。

關鍵字

太陽能電池材料 ； 光電轉換效率 ； 連結基

並列摘要

In this study, NMFP has been modified by different linkers and electron-donating groups to design a series of electron acceptor for BHJ (Bulk Heterojunction) solar cell fabrication. The optoelectronic properties of these designed electron acceptor, like band gap and UV-Vis spectra et al, have been characterized according to theoretically calculation. The effects from linkers and electron-donating groups to electron acceptor have been studied to design the electron acceptor of high LUMO (Lowest Unoccupied Molecular Orbital) or low band gap for enhancement of the efficiency of BHJ solar cell.
The results have demonstrated the linker with higher chain length has higher HOMO and the lower LUMO. Thus the Eg energy level has been also decreased. Due to the decreasing of Eg energy level, the major molecular orbital contribution of S0 to S1 was concentrated on the HOMO to LUMO transition. Compare to the compounds without linker modification, red shift and broadening of absorbance have been observed in the spectra of those electron acceptor modified by the designed linkers.
NMFP-L1 and NMFP-L3 are expected that they are suitable for developing so they were picked to be analyzed more. After combining with electron donors, the largest absorbed wavelengths of NMFP-L1 and NMFP-L3 had red shifts. Among these eight compounds, the surface of N-L3-D1 was the most planar, N-L3-D2 had the highest LUMO, N-L1-D4 had the lowest Eg, and N-L1-D2 was fine generally.

並列關鍵字

NMFP ； BHJ Solar Cell ； LUMO ； SIESTA ； DFT ； B3LYP

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