In situ Impedance Spectroscopic Study of Built-in Potentials in the Vicinity of the Donor/Acceptor Interface of Organic Solar Cells under Photo-irradiation
インピーダンス分光法を用いた有機薄膜太陽電池動作中でのドナー・アクセプター界面近傍における内蔵電位のin situ評価

Sou RYUZAKI, Jun ONOE
2012 Hyomen Kagaku  
Open-circuit voltage (VOC) plays a key role of determining the power conversion efficiency for solar cells, as well as short-circuit current. However, the origins of VOC have still remained unsolved for organic solar cells. Although VOC has been reported to depend on the electronic states at the Donor/Acceptor (D/A) interface such as the energy difference (DEHL) between HOMO (the highest occupied molecular orbital) of donor and LUMO (the lowest unoccupied molecular orbital) of acceptor, some
more » ... anic solar cells did not exhibit such the dependence. This is because previous discussion has been based on the D/A interfacial electronic states under "dark condition". Recently, we have performed in situ impedance spectroscopy to examine the correlation between VOC and the electronic states (built-in potential : Vbi) in the vicinity of the D/A interface upon photo-irradiation, and found an excellent agreement between VOC and the sum of Vbi estimated from capacitance-voltage (C-V) characteristics.
doi:10.1380/jsssj.33.93 fatcat:dnpx5ie3r5edxh3ifpnex66lsa