Luminescence quenching behavior of [Ru(bpy)2(dppz)]~(2+)-DNA/CdS/ITO electrode controlled synchronically by copper(II) ion and external electric field

摘要

A [Ru(bpy)2(dppz)]~(2+)-intercalated DNA film (bpy = 2,2'-bipyridine and dppz = dipyrido[3,2-a:2',3'-c]phenazine) is successfully assembled on an indium-tin oxide (1TO) electrode modified with CdS nanoparticles, designated as Ru(II)-DNA/CdS/ITO electrode. In the present protocol, [Ru(bpy)2(dppz)]~(2+) intercalated in the DNA film has contributed characteristic photoluminescence properties to the Ru(ll)-DNA/CdS/lTO electrode, in which CdS nanoparticles can bestow the tunable photovoltaic response. The as-prepared electrode shows a very consistent luminescence quenching by both applied anodic potentials and Cu(II) ions, which can extract the electrons from Ru(Il)-based excited states (λ_(EX) = 450nm). The photo-sensitive Ru(II)-DNA/CdS/lTO electrode is able to gain a maximum negative shift of ca. 0.467 V (open-circuit photovoltage vs. Ag/AgCl, 0.05 M NaCl) upon irradiation with UV-vis light between 350 and 700 nm. Additionally, the photovoltaic response including open-circuit photovoltage and short-circuit photocurrent for Ru(II)-DNA/CdS/ITO electrode (vs. Ag/AgCl) is also weakened by Cu(II) ions, indicating a synergistic effect with photoluminescence quenching. The preliminary results show a new approach to synchronically control the photoluminescence and photovoltaic response of DNA-metallointercalators and nanoconductor particles through the introduction of chemical agents, as well as open the way for optoelectronic switches.