石墨烯於有機太陽能電池電極及電洞傳輸層之應用

本研究為石墨烯於有機太陽能電池中電極及電洞傳輸層之應用。主要分為三部分。第一部分延續實驗室─石墨烯透明電極於雙面入光倒置結構太陽能電池之應用。製程加入溶劑蒸氣退火處理，以提升兩面的光電轉換效率。第二部分透過化學摻雜，藉摻雜物與石墨烯之間表面電荷轉移，改變石墨烯功函數和主要傳輸載子。使用了PEI、TiOx、BCP、TPBi做為N-摻雜物， F4-TCNQ為P-摻雜物，並將摻雜之石墨烯作為負極與正極。由實驗結果，知N-摻雜石墨烯作為P3HT系統之有機太陽能電池負極目前仍是個挑戰，而PEI摻雜之石墨烯是效果最佳之負極。最後一部分，利用石墨烯作為倒置結構之電洞傳輸層。其乾式轉印製程與有機太陽能電池現有溶液製程具有高的相容性。本研究結果顯示，石墨烯除了可作為一般倒置結構之電洞傳輸層；在使用低功函數鋁作為電極時，可將鋁的費米能階固定在石墨烯費米能階附近，克服了鋁電極功函數與光吸收層材料P3HT的HOMO能階不匹配導致效率不彰之狀況。這是需水溶性製程、且強酸性的PEDOT:PSS電洞傳輸層所無法克服的。而使用鋁電極/石墨烯電洞傳輸層元件具優良的光電轉換效率，達2.9%。因此，可用成本較低的鋁電極取代原本成本較高的銀電極。

關鍵字

石墨烯；電洞傳輸層；電極；摻雜

並列摘要

In this thesis, the graphene was applied as transparent electrodes and the hole transport layer in organic solar cells (OPVs). The first part was the graphene transparent electrode as the top anode of bifacial semitransparent inverted OPVs. Solvent vapor annealing process could enhance power conversion efficiency of both sides. In the second part, by chemical doping of graphene, the surface charge transfer between the dopant and the graphene changed the graphene work function and the majority carrier. The N-dopants PEI, TiOx, BCP, TPBi and P-dopant the F4-TCNQ were used. Furthermore, N-doped and P-doped graphene were applied as cathode and anode respectively. From the experimental results, the N-doped graphene as a cathode of OPVs based on P3HT:PCBM was still a challenge, and PEI-doped graphene was a more effective cathode. The final part was graphene hole transport layer of inverted OPVs. There was high compatibility of dry transfer process of graphene and solution process of OPVs. The results shown that graphene as a hole transport layer of inverted OPVs, not only worked under the general high work function electrode as anode but also worked under low work function aluminum electrode as anode. The aluminum Fermi level was pinned near the graphene Fermi level, which overcame the mismatch of the aluminum electrode work function and light absorption layer material P3HT HOMO energy level that caused low power generation efficiency. And it exhibited a high power conversion efficiency of 2.9%. Therefore, the lower-cost aluminum electrode was available to replace the original high cost of silver electrode.

並列關鍵字

graphene ； hole transport layer ； electrode ； dope

參考文獻

1. Solar cell efﬁciency tables (version 39)

2. National Renewable Energy Laboratory

3. M. Pope, C. E. Swenberg, Electronic Processes in organic crystals and polymers, 2nd ed., Oxford University Press, New York 1999

4. S. Barth, H Bassler, Phys. Rev. Lett. 1997 79 4445

5. P. G. Dacosta, E.M. Conwell, phys. Rev. B 1993, 48.

國際替代計量

石墨烯於有機太陽能電池電極及電洞傳輸層之應用

主題瀏覽