Abstract
The present research has focused on the electron diffusion simulation in titanium oxide (TiO2) after ultrafast electron injection from attaching gold (Au) nanoparticles measured by femtosecond spectroscopy using Monte Carlo random walk. While the recombination phenomenon is anticipated to be significantly influenced by the external structure of TiO2, this effect has not been thoroughly researched. In this study, the simulation experiments were conducted with the electron diffusion originating from the center of the circle. The diffusing electron encounters in-boundary reflectance within the range of 15°-345°, and experiences out-of-boundary absorption between 0°-15° and 345°-360°. The program allows for boundary and radius step-size adjustments to bring the simulated surface closer to the actual surface of the TiO2 nanostructure. The histograms corresponding to the occurrence frequency of the out-of-boundary absorption are obtained. Furthermore, the boundary and radius step-size are adjustable, we gave scatter plot of their different particle positions and their density plot. The charge recombination process is influenced by the carrier diffusion length with variable step size radius; by variable boundary, nanoparticles and lifetime conform to the experimental quadratic relationship were verified.