Sol-gel synthesis was used to develop a new hybrid photoanode material, a spherical zinc stannate/tin oxide nanorod named ZSTP. The subsequent step involves doping ZSTP with silver using a precursor called silver nitrate. The undoped sample was labelled as ZSTP, whereas silver-doped composites containing 1, 2, and 3 wt% silver were labelled as ZSTP-Ag1, ZSTP-Ag2 and ZSTP-Ag3 respectively. The pattern of powder X-ray diffraction (PXRD) with 2θ values of 26.52 and 33.84 confirms the orthorhombic structure of ZSTP and silver-doped samples. In the FT-IR spectra of the ZSTP and their silver-doped samples, the stretching frequency for Zn–O–Sn is observed at 1100 and 1464 cm−1. In addition, the surface-adsorbed Ag peaks at 1384 cm−1. The XPS spectra of ZSTP-Ag3 confirms the existence and structure of SnO and Ag. Examining the morphology with a scanning electron microscope (SEM) and transmission electron microscope (TEM) reveals a porous structure with adsorbed Ag on the surface. Doped silver appears as tiny spherical particles on the surfaces, whereas SnO nanorod zinc stannate appears as spherical particles in the TEM image. In-depth optical experiments were conducted to evaluate the characteristics of hybrid composites for DSSC applications. It was explored how the dye aggregates on the surface of silver-doped ZSTP. On the basis of the energy levels of their conductance bands, the electron transfer kinetics and energy transfer mechanism were predicted. Under a conventional one-sun illumination condition, the output photocurrent and photovoltage of these DSSC materials are evaluated. ZSTP-Ag3 offered the highest PCE at 1.38%. Due to the role of Ag2O in electron transfer, silver doped samples based devices offer a high FF (0.7) and steady photovoltage. Using the photovoltage decay curve, the recombination time (τrec) and rate (krec) were calculated to confirm a slower rate of recombination. Using simulated results, the overall performance of the DSSC is compared and validated.
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