The Role of Antireflective Coating CYTOP, Immersion Oil, and Sensitizer Selection in Fabricating a 2.3 V, 10% Power Conversion Efficiency SSM-DSC Device

摘要

Sequential series multijunction dye-sensitized solar cells (SSM-DSCs) can power solar-to-fuel processes with a single illuminated area device. Dye selection and strategies limiting photon losses are critical in SSM-DSC devices for higher performance systems. Herein, an efficient and readily applicable spin coating protocol on glass surfaces with an antireflective fluoropolymer (CYTOP) is applied to an SSM-DSC architecture. Combining CYTOP with the use of an immersion oil between glass spacers in a three subcell SSM-DSC with judiciously selected TiO2 photoanode sensitizers and thicknesses, an overall power conversion efficiency (PCE) of 10.1% is obtained with an output of 2.3 V. Without external bias, this SSM-DSC configuration shows an impressive overall solar-to-fuel conversion efficiency of 6% when powering IrO2 and Au2O3 electrocatalysts for CO2 and H2O to CO and H-2 conversion in aqueous solution. The role of CYTOP, immersion oil, sensitizer selection, and film thickness on SSM-DSC devices is discussed along with the stability of this system.