Thermoelectric properties of doped small molecule organic semiconductor films

Doped films of organic small molecules are investigated with respect to their thermoelectric properties. A variety of hosts and dopants, for both n and p-doping, are compared. C$_{60}$ n-doped by Cr$_2$(hpp)$_4$ or o-MeO-DMBI-I are found to be the most promising material systems with a maximum of ZT$_\text{M}$ = 0.069 at T$_\text{M}$ = 40{\deg}C, assuming a doping-independent thermal conductivity due to phonon-based heat transport. This value is 16% of the current record reported for optimized devices employing the doped polymer PEDOT:PSS.