2. Materials and methods
2.1. Electrical setup for voltage excitation
Voltage excitation of the reaction system was executed using the in-house built custom electrical setup presented in Fig. 1 (a). Design of the setup is based on the OPA547 operational amplifier and a sound card digital-to-analog converter (SC DAC). Waveform shape, amplitude and frequency at the SC DAC output were adjusted manually in LabVIEW based software (Soundcard Scope, version 1.41). The excitation voltage signal was amplified using the non-inverting operational amplifier configuration with the gain of 11 and the output current was limited by the trimmer potentiometer. The constructed excitation device can provide accurate and stable sinusoidal AC voltage excitation within the amplitude range of (0.1–10) V and frequency range of (0.01–10) kHz having a continuous current output amplitude of up to 0.5 A. Low cost, modularity, reliability and simplicity of the setup make it very attractive and suitable for versatile research applications in materials science. Design details and specific considerations are discussed in the supplementary section “Electronic device design”.