MODIFICATION OF TIO2 ELECTRODE WITH A SERIES OF ALKALINE-EARTH CARBONATES: PERFORMANCE IMPROVEMENT OF QUASI-SOLID-STATE DYE-SENSITIZED SOLAR CELLS

摘要

In this paper, alkaline-earth carbonates (CaCO3, SrCO3 and BaCO3) modified TiO2 electrodes are synthesized by dipping TiO2 electrode into alkaline-earth hydroxide or alkaline-earth acetate aqueous solutions. When applied to quasi-solid-state DSSC, hydroxide-treated TiO2 electrodes have increased open-circuit photovoltages (Voc). Among the three alkaline-earth hydroxides, Ba(OH)2 treatment improved the DSSC performance best. The Voc improves from 0.66 V to 0.71 V and the overall conversion efficiency (η) improves by 15% under100 mW/cm2.As to acetates, not only the Voc is increased (from 0.68V to 0.74V), but also short-circuit photocurrent(Isc) is improved by Sr(OAc)2、Ba(OAc)2 The overall conversion efficiency improves by 22%. Dark current measurement indicate that in the presence of alkaline-earth carbonates, the TiO2 conduction band shifts to the negative direction, leading to the increase in Voc.