Prediction of Power Conversion Efficiencies of Diphenylthienylamine-Based Dyes Adsorbed on the Titanium Dioxide Nanotube

[Image: see text] The power conversion efficiency (η) is the most important key to determine the efficiency of dye-sensitized solar cell (DSSC) devices. However, the calculation of η theoretically is a challenging issue since it depends on a large number of experimental and theoretical parameters with extensive related data. In this work, η was successfully predicted using the improved normal model with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for eight diphenylthienylamine-based (DP-based) dyes with various π-bridge adsorbed on titanium dioxide. The titanium dioxide is represented by a nanotube surface (TiO(2)NT); this surface is rarely investigated in the literature. The π-linker consists of five (DP1)- or six (DP2)-membered rings and contains none to three nitrogen atoms (D0–D3). The reliability of the estimated values was confirmed by the excellent agreement with those available for the two experimentally tested ones (DP2-D0 and DP2-D2). The deviations between the experimental and estimated values were in the ranges of 0.03 to 0.06 mA cm(–2), 0.05 to 0.3 mV, and 0.37 to 0.18% for short-circuits current density (J(sc)), open-circuit voltage (V(oc)), power conversion efficiency (%η), respectively. More importantly, the results revealed that using pyridine (DP2-D1), pyrimidine (DP2-D2), and 1,2,4-triazine (DP2-D3) improves the power conversion efficiencies in the range of 6.03 to 6.90%. However, the cyclopenta-1,3-diene (DP1-D0) shows superior performance with a predicted η value that reaches 9.55%.