Modeling disorder in two-dimensional colloidal crystals based on electron microscope measurements.

Abstract

Self-assembled two-dimensional colloidal crystals (CCs) are critical components in many optical and optoelectronic devices. Such structures usually exhibit various types of disorder, which sometimes can be beneficial for the desired applications. However, disorder poses challenges to the modeling of two-dimensional structures. In this work, two-dimensional CCs employed in optoelectronic devices, especially dye-sensitized solar cells, are investigated. scanning electron microscope (SEM) images were used to quantify the disorder in the studied structures. As a basis for simulations, disordered model patterns were generated with properties extracted from the SEM images of prepared samples. Optical modeling was performed with a finite-difference time-domain simulator. The simulated transmission data are consistent with the experimentally measured spectra.