A Versatile System for Arbitrary Function Large‐Amplitude Fourier Transformed Voltammetry

Abstract

AbstractA novel low‐cost instrument for arbitrary function large‐amplitude Fourier transformed voltammetry was developed. Description of both hardware and software was given in detail in this paper. A micro‐control‐unit (MCU) in combination with a field programmable gate array (FPGA) was designed to act as the controller of the instrument. Profiting from the built‐in USB2.0 standard interface of the MCU, vast amount of data to/from the high resolution digital‐to‐analog converter (DAC)/analog‐to‐digital converter (ADC) then could be exchanged with computer in real‐time, instead of being temporarily stored at the capacity limited memory of the instrument which always restricted the length of sampling time and the size of the collected data set. In the [Fe(CN)6]4+/3+ system, by superimposing a sinusoidal waveform with an amplitude of 120 mV onto a triangular potential and then applying to a macro electrode through the instrument, voltammograms up to the eighth harmonic could be well resolved by FT‐IFT method. Excellent agreement was attained with Bond's similar experiment [Anal. Chem. 76 (2004) 3619] in respect of the shape and relative peak height of each harmonic. With the simply structured instrument, stable performance, flexible and versatile function was achieved. Arbitrary forms of AC perturbation which may not necessarily be sinusoidal or square‐wave or other regular formed periodic signal could be synthesized and superimposed onto a DC potential as the excitation signal with this instrument. Some more useful electrode process information was expected to unveil by utilizing the FT‐IFT algorithm to dissect the response signal.