1：Experimental Design and Method Selection:

The geometry optimization for each Triphenylamine-based dye (TPA), in free and adsorbed forms, was fully performed by density functional theory (DFT), by using the hybrid B3LYP-DNP functional. The DNP (including polarization d-function), which is similar to the Gaussian09 6-31G (d, p) basis set, and has higher accuracy than other available basis sets, was selected as a basis set here. For the electronic structure, single-point calculations were performed using the hybrid B3LYP functional, with the same basis set. The dye electronic absorption spectra were calculated using time-dependent density functional theory (TD-DFT). For the geometry optimization and optical properties, the convergence tolerance of energy was

2：0 ×10?6 Ha, and the maximum force was considered as 0004 Ha/? with maximum displacement 0005 ?. Sample Selection and Data Sources:

To determine the relative stability of dye molecule adsorption onto the (101) surface of a given (ZnTiO3)8 perovskite cluster (involving 8 Zn atoms, 8 Ti atoms and 24 O atoms), full geometry optimization was conducted using the DMol3 code. The DFT-D approach was applied to treat the weak (Van der Waals, vdW) interactions between TPA dye carboxylic groups (COOH) and ZnTiO3 surfaces. To check the geometrical parameters and adsorption energy of (TPA@ZnTiO3) complex systems the periodic DFT geometry optimizations have been performed within the generalized gradient approximation (GGA) using the PBE exchange–correlation functional.

3：List of Experimental Equipment and Materials:

All calculations were performed with the BIOVIA MATERIALS STUDIO package.

4：Experimental Procedures and Operational Workflow:

The methodology involved the use of DFT, TD-DFT, and hybrid B3LYP-DNP functional for the simulation of 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.

5：Data Analysis Methods:

The results were analyzed to assess electron transfer efficiency between the excited dyes and the ZnTiO3 particles, and to compare the characteristics of the four TPA dyes.