Current-time measurements were conducted using B2901A (Keysight Technologies). The desired voltage was applied, and the current was recorded against time. We set a light emitting diode (with wavelengths of 680 nm, 490 nm, or 405 nm) above the mat and turned the light on and off at specified intervals. The irradiation power was controlled by the power controller and determined using a power meter. Gold finger electrodes distanced at 1 mm or 8 mm were used for the current-time measurements.