Experimental methods in chemical engineering: Cyclic voltammetry— CV

Abstract

Cyclic voltammetry (CV) is a foundational electroanalytical technique for investigating redox behaviour and evaluating material performance across fields such as molecular electrochemistry, electrocatalysis, sensing, and energy storage. Despite its widespread use, a gap remains between formal electrochemical theory and the practical data analysis required for chemical engineering applications. This review addresses that gap by treating the voltammogram as a multidimensional source of mechanistic and quantitative information rather than as a purely qualitative profile. A theoretical framework is presented for CV, including the governing principles of interfacial electron‐transfer kinetics, mass‐transport regimes, and the distinction between capacitive currents and faradaic processes. To support reliable and reproducible measurements, practical guidance is provided for controlling key experimental variables, including uncompensated resistance, supporting electrolyte effects, scan rate, and potential window selection. Beyond basic peak identification, methods for extracting and interpreting quantitative descriptors are also discussed, including formal and onset potentials, apparent rate constants, electrochemically active surface area, transport regimes, apparent Michaelis–Menten parameters, and capacitance‐ or capacity‐based metrics. Particular attention is given to major sources of uncertainty, including non‐ideal mass transport, film heterogeneity, and fouling, which can distort mechanistic interpretation in complex engineering systems. Recent integration of CV with operando mass spectrometry, spectroscopy, and nanoscale imaging further illustrates how the technique has evolved into a coordinated platform for mechanistic and process‐level analysis in electrochemical engineering. In doing so, the review highlights how CV can support the rational design of robust and scalable electrochemical technologies.