Title: Effects of solvents on the band energetics of nanostructured BaTiO3 electrodes for dye sensitised solar cells
Authors: Hongjun Wang; Qi Zhang; Wenbo Zhang; Shuming Yang
Addresses: College of Chemistry and Chemical Engineering, Xinyang Normal University, Henan, 464000, China ' Laboratory of Mesoscopic Functional Matetials and Devices, Huazhong University of Science and Technology, Hubei, 430000, China ' College of Chemistry and Chemical Engineering, Xinyang Normal University, Henan, 464000, China ' College of Chemistry and Chemical Engineering, Xinyang Normal University, Henan, 464000, China
Abstract: The flat band edges (Efb) of nanostructured BaTiO3 electrodes were determined in acetonitrile (ACN), acetylacetone (Acac) and ACN/Acac with spectroelectrochemistry measurements. Efb of −1.1, −1.01 and −0.82 V and the total trap state densities of 1.32 × 1016, 3.63 × 1015 and 1.72 × 1015 cm−2 were measured in ACN, Acac and ACN/Acac (all containing 0.2 mol • L−1 TBAP) with trap distribution maximum located at −0.9, −0.8 and −0.3 V. The nanostructured BaTiO3 electrodes were sensitised with dye N719 and its photovoltage-photocurrent curves were characterised in three electrolytes with ACN, Acac and ACN/Acac as solvent respectively. The N719 sensitised BaTiO3 showed the highest open-circuit voltage and short-circuit current density in ACN/Acac. The results demonstrated solvents had an important effect on Efb and the trap state densities of nanostructured BaTiO3 electrodes. Efb shifted positive as the coordination ability of solvents became strong, and the corresponding Ntrap decreased.
Keywords: dye-sensitised solar cells; DSSC; nanostructured BaTiO3; BaTiO3 electrodes; barium titanate; spectroelectrochemistry; band energetics; trap state; solvents; nanotechnology.
International Journal of Nanomanufacturing, 2016 Vol.12 No.3/4, pp.216 - 224
Received: 19 Jun 2015
Accepted: 04 Jan 2016
Published online: 23 Sep 2016 *