PassStat, a simple but fast, precise and versatile open source potentiostat

Area of Science:

• Electrochemistry
• Instrumentation
• Open-source hardware

Background:

• Accurate electrochemical measurements are crucial in various scientific fields.
• Existing potentiostat solutions can be prohibitively expensive, limiting accessibility.
• There is a need for low-cost, reproducible instrumentation for research and education.

Purpose of the Study:

• To develop and present four open-source potentiostat solutions.
• To enable accurate cyclic voltammetry (CV) and square wave voltammetry (SWV) measurements at a low cost.
• To provide accessible instrumentation for diverse settings, including education and resource-limited regions.

Main Methods:

• Designed a simple, reproducible analogic board (approx. €10).
• Integrated the board with a Teensy microcontroller (Arduino/Python software, €39) or an Analog Discovery 2 (Digilent, <€300).
• Developed a smartphone Bluetooth Android interface to eliminate the need for a computer.

Main Results:

• Demonstrated suitability for classical electrochemical conditions and ultramicroelectrode experiments.
• Achieved a noise resolution of less than 1 picoampere (pA).
• Reached scan rates of 8000 V/s with ohmic drop compensation.

Conclusions:

• The developed open-source potentiostats offer accurate electrochemical measurements at a significantly reduced cost.
• The solutions are versatile, suitable for teaching, citizen science, and researchers in financially constrained areas.
• The system provides high performance, including low noise and high scan rates, comparable to more expensive commercial instruments.