Differential Square-Wave Voltammetry

A new voltammetric technique designed as a hybrid between differential pulse and square-wave voltammetry is proposed for the purpose of unifying the advantages of both techniques, i.e., the ability to provide mechanistic information, studying electrode kinetics of both sluggish and very fast electrode reactions, and the ability to suppress effectively residual background current. Voltammetric modulation of the hybrid technique consists of a staircase potential combined with square-wave potential modulation superimposed at the end of each potential step. By measuring the current at the end of each potential step and pulse, differential forward and backward voltammetric components can be composed, which is a unique ability of the hybrid technique. In addition, by analogy to square-wave voltammetry, a net differential component can be contracted with improved analytical performances compared to square-wave voltammetry. The proposed technique opens a new avenue for an advanced analysis of electrochemical processes and analytical application.