Application of two Cu(II)-azido based 1D coordination polymers in optoelectronic device: Structural characterization and experimental studies

Two new azido bridged 1D polymeric Cu(II) chains, [Cu(L-1)(mu(1,3)-N-3)](infinity) (1) and [Cu-2(L-2)2(mu(1,1)-N-3)(mu(1,3)-N-3)](infinity) (2) have been synthesized by using two different N2O donor tridentate reduced Schiff base ligands, HL1 = 2-[(2dimethylamino-ethylamino)-methyl]-4-nitrophenol, HL2 = 2-[(2-diethylamino-ethylamino)-methyl]-4-nitrophenol and both are structurally characterized. Cu(II) ions in both complexes occupy distorted pentacoordinated square pyramidal geometry. Both structures form polymeric chains, in 1, via mu(1,3)-N-3(-) while in 2 via both mu(1,1)-N-3(-) and mu(1,3)-N-3(-) bridges. The band gaps of the complexes (2.91 eV for 1 and 2.89 eV for 2) suggest that both polymeric chains are semiconducting and thus possess the potential for uses in devices. A detail I-V analysis was performed to measure device related parameters i.e. effective carrier mobility, transit time, carrier concentration, diffusion length and ideality factor. The results show that both polymeric chains behave as Schottky barrier diodes (SBD) and could be used in opto-electronic device. Between the two complexes, 2 performs better than 1 in terms of applicability as indicated by the calculated parameters.