High electron mobility in bathophenanthroline

We have measured electron mobility in vacuum-deposited films of 4,7-diphenyl-1,10phenanthroline (bathophenanthroline, or BPhen) using a time-of-flight technique. Electron transport was highly dispersive for BPhen with a dispersion parameter of a value 0.30. The electron mobility in excess of 10−4 cm2/V s has been observed at electric fields of the order of 105 V/cm with weakly dependent on the electric field. The characteristic energy of the distribution is obtained a value 0.09 eV. It is directly confirmed that the BPhen has superior electron-transport capability.