Figure illustrates the endpoint of a simulation, showing the distribution of four different types of ECL compounds in a two-dimensional geometry with dimensions of 40 µm in length and 100 nm in height. The simulation begins with a particles undergoing a random walk. In the segment spanning from 10 µm to 30 µm, electrochemical reactions (1) and ( ) occur at the bottom of the geometry, while reactions ( ) and ( ) take place at the top. The annihilation reaction (3) and subsequent decay and luminescence (4) proceed throughout the entire geometry. The Python script for this simulation is provided in the Appendix and available at: .