Synthesis and characterization of TiO2 on ZnO-nanorod layer for high-efficiency electrochemiluminescence cell application

Abstract

In this research paper, we present the fabrication of an electrochemiluminescence (ECL) cell with TiO2 on ZnO-nanorod electrodes via the dip-coating technique. The TiO2 nanoparticles coated on ZnO nanorods (TiO2-ZNRs) were grown on transparent conductive oxide (TCO) glass by the dip-coating technique. The electrode of TiO2-ZNRs for ECL cells has the structure F-doped SnO2 (FTO) glass/Ru(II) complex [Ru(bpy)32+]/TiO2-ZNRs/FTO glass. The TiO2-ZNRs were coated on FTO glass by spin-coating and dip-coating methods. The X-ray diffraction system, scanning electron microscope, and spectral brightness analyzer were used to confirm the successful formation of the structure and the morphological properties. The threshold voltage at the start of light emission was 2.25 V for TiO2-ZNRs and was lower than 3.25 V for bare FTO. The threshold voltage was l2.5 V for ZNRs. The electrical and optical properties of the TiO2-ZNRs ECL cell were 30.76 cd/m2 light intensity, 0.067 mA output current, 0.268 cd/A (at 9.67 mA/cm2) current efficiency, and 0.068 lm/W ECL efficiency at 5 V and 60 Hz. The peak intensity of the TiO2-ZNRs-based ECL cell at a wavelength of 621 nm exhibited a dark orange color and was independent of the type of electrode used. The use of TiO2-ZNRs could improve the ECL efficiency and long-lifetime stability.