Investigation of triphenylamine-based sensitizer characteristics and adsorption behavior onto ZnTiO3 perovskite (1 0 1) surfaces for dye-sensitized solar cells using first-principle calculation

Abstract

Four different Triphenylamine-based dyes, named as TPA-1, TPA-2, TPA-3 and TPA-4 as shown below, with substituents containing different linkages, earlier described inTiO2dye-sensitized solar cells (DSSCs), are described. The dyes are examined as potential dyes for perovskite ZnTiO3 based dye sensitized solar cells (DSSCs). The simulated characteristics include: Electronic absorption spectra, light harvesting efficiency, energy of dye adsorption to the semiconductor ZnTiO3 electrode, energy level alignment and spontaneity of charge transfer across the dye interfaces with ZnTiO3 and with solution redox couple. The characteristics have been comparatively investigated for all dyes. The absorption spectra for each dye, in its free and adsorbed forms, are discussed. Energy levels and electrochemical parameters are investigated to assess electron transfer efficiency between the excited dyes and the ZnTiO3 particles. Among the series, the dye TPA-3 shows superior behaviors, in terms of spontaneity of charge transfer with ZnTiO3 conduction band. The dye exhibits bidentate mode bonding with the semiconductor surface (1 0 1) as evidenced from its high adsorption energy. Such bonding enables stronger adherence between the dye and the semiconductor and enables more efficient charge transfer. The results encourage more theoretical and experimental study on TPA-3@ZnTiO3 DSSCs, with promising conversion efficiency and stability.