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

This work presents 4 open source potentiostat solutions for performing accurate measurements in cyclic voltammetry and square wave voltammetry at a low price. A very simple and easy to reproduce analogic board (c.a. 10 €) was driven either by a Teensy card from the company PJRC under an Arduino/Python software solution (39 €) or by an Analog Discovery 2 device from Digilent (less than 300 €). A smartphone Bluetooth Android interface was also created to circumvent the use of a computer. We demonstrated that our scheme is suitable for measurements in classical electrochemical conditions but also to carry out experiments with ultramicroelectrodes. We could thus reach a noise resolution of less than 1 pA. Scan rates of 8000 Vs^-1 with ohmic drop compensation were also achieved. The device is suitable for teaching purposes but also for experiments in a participative science context on the ground, or countries with lower financial possibilities.