Polymer PCE11 was targeted by reacting 4,7-bis(5-bromo-4-(2-octyldodecyl)thiophen-2-yl)-5,6-difluorobenzo[c][1,2,5]-thiadiazole with 2,5-bis(trimethylstannyl)thieno[3,2-b]thiophene engaging Stille Coupling reaction.

General Information

Chemical Structure

Device Structure(s)

The structure of the high-performance (10 - 11%) devices was:

ITO / ZnO / PffBT4T-2OD:PC70BM (200 – 300 nm) / MoO3 or V2O5 (20 nm) / Al (100 nm)

PffBT4T-2OD:PC70BM solution details:

• Blend ratio: 1:1.2,

• Polymer concentration: 9 mg/ml,

• Solvent: 1:1 blend of chlorobenzene and dichlorobenzene,

• Additive: 3% diiodooctane,

• Heating: 85°C for dissolution,

It is important to note that this solution (and the substrate being deposited onto) must be heated for spin casting, with the ideal temperature being 60 – 80°C. It is reported that a solution and substrate pre-heating temperature of 110°C should be used to allow for cooling that will occur before deposition.