A porphyrin-based donor material P1 is used to fabricate bulk-heterojunction solar cells harvesting room light. P1 consists of a porphyrin ring linked by two ethylrhodanine end caps via phenylene ethynylene bridges. Organic photovoltaic (OPV) cells using P1 as the donor exhibit significantly improved performances under indoor illumination compared to 1 sun conditions. For P1:PC71BM cells, an optimized-PCE of 19.2% was achieved under a 300 lux illumination of a 3000 K LED tube. Besides high PCEs, the porphyrin-based devices also exhibit enhanced OPV performances in thick film regions (∼200 nm) compared to a control BHJ cell using PCDTBT:PC71BM. The thick-film P1-based device shows an overall PCE of 18.2%. The origins of the thickness independent OPV performances were examined, and they can be attributed to the low electronic disorders of these materials when compared to their polymer counterparts.
Scopus Subject Areas
- Materials Chemistry