TY - JOUR
T1 - Semi-transparent tandem organic solar cells with 90% internal quantum efficiency.
AU - Tang, Zheng
AU - George, Zandra
AU - Ma, Zaifei
AU - Bergqvist, Jonas
AU - Tvingstedt, Kristofer
AU - Vandewal, Koen
AU - Wang, Ergang
AU - Andersson, Lars
AU - Andersson, Mats R.
AU - Zhang, Fengling
AU - Inganas, Olle
PY - 2012/12
Y1 - 2012/12
N2 - Semi-transparent (ST) organic solar cells with potential application as power generating windows are studied. The main challenge is to find proper transparent electrodes with desired electrical and optical properties. In this work, this is addressed by employing an amphiphilic conjugated polymer PFPA-1 modified ITO coated glass substrate as the ohmic electron-collecting cathode and PEDOT: PSS PH1000 as the hole-collecting anode. For active layers based on different donor polymers, considerably lower reflection and parasitic absorption are found in the ST solar cells as compared to solar cells in the standard geometry with an ITO/PEDOT: PSS anode and a LiF/Al cathode. The ST solar cells have remarkably high internal quantum efficiency at short circuit condition (∼90%) and high transmittance (∼50%). Hence, efficient ST tandem solar cells with enhanced power conversion efficiency (PCE) compared to a single ST solar cell can be constructed by connecting the stacked two ST sub-cells in parallel. The total loss of photons by reflection, parasitic absorption and transmission in the ST tandem solar cell can be smaller than the loss in a standard solar cell based on the same active materials. We demonstrate this by stacking five separately prepared ST cells on top of each other, to obtain a higher photocurrent than in an optimized standard solar cell.
AB - Semi-transparent (ST) organic solar cells with potential application as power generating windows are studied. The main challenge is to find proper transparent electrodes with desired electrical and optical properties. In this work, this is addressed by employing an amphiphilic conjugated polymer PFPA-1 modified ITO coated glass substrate as the ohmic electron-collecting cathode and PEDOT: PSS PH1000 as the hole-collecting anode. For active layers based on different donor polymers, considerably lower reflection and parasitic absorption are found in the ST solar cells as compared to solar cells in the standard geometry with an ITO/PEDOT: PSS anode and a LiF/Al cathode. The ST solar cells have remarkably high internal quantum efficiency at short circuit condition (∼90%) and high transmittance (∼50%). Hence, efficient ST tandem solar cells with enhanced power conversion efficiency (PCE) compared to a single ST solar cell can be constructed by connecting the stacked two ST sub-cells in parallel. The total loss of photons by reflection, parasitic absorption and transmission in the ST tandem solar cell can be smaller than the loss in a standard solar cell based on the same active materials. We demonstrate this by stacking five separately prepared ST cells on top of each other, to obtain a higher photocurrent than in an optimized standard solar cell.
UR - http://www.scopus.com/inward/record.url?scp=84867766375&partnerID=8YFLogxK
U2 - 10.1002/aenm.201200204
DO - 10.1002/aenm.201200204
M3 - Article
VL - 2
SP - 1467
EP - 1476
JO - Advanced Energy Materials
JF - Advanced Energy Materials
SN - 1614-6832
IS - 12
ER -