Publication Date:
2016-07-13
Description:
In this work, we report enhanced power conversion efficiency (PCE) of bulk heterojunction polymer solar cells by Förster resonance energy transfer (FRET) from samarium-doped luminescent gadolinium orthovanadate (GdVO 4 :Sm 3+ ) quantum dots (QDs) to polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) polymer. The photoluminescence emission spectrum of GdVO 4 :Sm 3+ QDs overlaps with the absorption spectrum of PTB7, leading to FRET from GdVO 4 :Sm 3+ to PTB7, and significant enhancements in the charge-carrier density of excited and polaronic states of PTB7 are observed. This was confirmed by means of femtosecond transient absorption spectroscopy. The FRET from GdVO 4 :Sm 3+ QDs to PTB7 led to a remarkable increase in the power conversion efficiency (PCE) of PTB7:GdVO 4 :Sm 3+ :PC 71 BM ([6,6]-phenyl-C 71 -butyric acid methyl ester) polymer solar cells. The PCE in optimized ternary blend PTB7:GdVO 4 :Sm 3+ :PC 71 BM (1:0.1:1.5) is increased to 8.8% from 7.2% in PTB7:PC 71 BM. This work demonstrates the potential of rare-earth based luminescent QDs in enhancing the PCE of polymer solar cells.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
Permalink