Digital Circuit for Fast Scan Voltammetry Based on Dual-Frequency Method.

In this work, a digital circuit for fast scan voltammetry (FSV) was developed based on dual-frequency method. It consists of six main modules including the microcontroller unit, signal generator module, solution resistance measurement module, ohmic drop automatic compensation module, keying module and display module. By online measuring the solution resistance without any interference from capacitive impedance first, the ohmic drop compensation could be precisely carried out, bringing reliable FSV detection. RC dummy cell, dummy cell with pseudo-Faradaic impedance and actual electrochemical cell were used to verify the performance of automatic ohmic drop compensation. Results show that, FSV could be performed using a conventional electrode with the scan rate up to 2400 V/s. And, a handheld device was manufactured with a weight of 100 g and a size of 9 × 6 × 3 cm, costing only $35. It provides a simple, reliable and stable FSV plateau for electrochemical detection. [ABSTRACT FROM AUTHOR]