Abstract
We report here an original approach to dope the semiconducting polymer-metal interface in an inverted bulk-heterojunction (BHJ) organic solar cell. Solution-processed 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), is deposited on top of a P3HT:PC61BM layer before deposition of the top electrode. Doping of P3HT by F4-TCNQ occurs after thermally induced diffusion at 100 °C of the latter into the BHJ. Diffusion and doping are evidenced by XPS and UV-vis-NIR absorption. XPS highlights the decrease in Fluorine concentration on top of the BHJ after annealing. In the same time, a charge transfer band attributed to doping is observed in the UV-vis-NIR absorption spectrum. Inverted polymer solar cells using solution-processed F4-TCNQ exhibit power conversion efficiency of nearly 3.5% after annealing. This simple and efficient approach, together with the low annealing temperature required to allow diffusion and doping, leads to standard efficiency P3HT:PC61BM polymer solar cells, which are suitable for printing on plastic flexible substrate.
Original language | English (US) |
---|---|
Pages (from-to) | 9262-9267 |
Number of pages | 6 |
Journal | ACS Applied Materials and Interfaces |
Volume | 8 |
Issue number | 14 |
DOIs | |
State | Published - Apr 27 2016 |
All Science Journal Classification (ASJC) codes
- Materials Science(all)
Keywords
- F-TCNQ
- doping
- hole transport layer
- polymer solar cells
- solution-processing