Opening the Potentiostat “Black Box”: A Low-Cost and Highly Integrated Instrumentation Demonstration for Undergraduates

Potentiostats are central to electrochemical measurements, yet their operating principles are rarely taught in undergraduate chemistry education. Consequently, students often treat the instrument as a “black box” that converts input parameters into electrochemical curves without understanding the underlying hardware logic and feedback principles. Herein, we report a visually intuitive and accessible instructional demonstration that opens this black box by combining low-cost potentiostat assembly with cyclic voltammetry (CV) measurements using screen-printed electrodes (SPEs). This activity provides a complete learning workflow encompassing two- and three-electrode systems, operational-amplifier feedback circuits, electronic-component assembly, graphical software operation, instrument verification, and CV measurements. A Lego-like modular kit further allows each student group to independently build a functional potentiostat. The use of highly integrated, inexpensive SPEs in place of conventional electrochemical cells and individual electrodes further simplifies the experimental setup and reduces material costs. Evaluated through activity completion and postdemonstration exercises, this demonstration integrates electrochemistry, instrumentation, electronic circuit, and data analysis into one interdisciplinary activity, at a cost low enough for wide classroom adoption.