Enhanced Electrochemiluminescence by Use of Nanoporous TiO2 Electrodes: Electrochemiluminescence Devices Operated with Alternating Current

It was found that electrochemiluminescence is enhanced by the use of nanoporous TiO2 electrodes. The nanoporous TiO2 electrodes were fabricated by cumulating nano-TiO2 crystals on the transparent conductive layers (SnO2/F). The device was composed of the porous TiO2 electrodes (10 µm) and SnO2/F electrodes as counterelectrodes. The gap was filled with electrolytes containing Ru(bpy)3(PF6)2 (bpy: bi-pyridyl) in various solvents. The electrochemiluminescence was much larger than that from the cell composed of two flat SnO2/F electrodes. It is likely that the increase in elecrochemiluminescence is associated with the nanopores as well as with the large surfaces of porous semiconductive oxide electrodes.