Photovoltage study of charge injection from dye moleculesinto transparent hole and electron conductors

Transient and spectral photovoltage $(PV)$ have been investigated for charge injection from a dye $[Ru(dcbpyH2)2(NCS)2]$ into transparent hole (⁠$CuSCN$⁠, $CuI$⁠, $CuAlO2$⁠) and electron (⁠$TiO2$⁠, $SnO2:F$⁠) conductors. The $PV$ signal rises to a maximum within $10ns$ to $10μs$⁠, depending on the transparent hole or electron conductor and on the mechanism of charge separation. The efficiency of hole and electron injection is of the same order while the effective lifetimes of injected charge vary between several $μs$ and $1ms$ for the samples used. The thresholds for charge injection from the dye range between 1.6 and $1.8eV$ depending on the material on which the dye is adsorbed.