Nuances of the voltammetry of homogeneous multi-electron molecular catalysts: An analytical theory for two-electron catalysis

•New theory is provided for the voltammetric study of two-electron molecular catalysts.•Any catalytic kinetics and cooperativity between electron transfers are covered.•Criteria are discussed to identify the active species and pathways of the catalysis.•Guidelines are presented to assess the catalytic performance.•Pure kinetic conditions can be very difficult to achieve in multi-electron catalysis.