Electrochemical flow cells for laboratory electrocatalysis: Hydrodynamics, operando analysis, and automation

Reliable assessment of electrocatalytic activity, selectivity, and stability relies on controlling the local reaction environment, which is in turn modulated by mass transport at the electrode. Electrochemical flow cells are emerging as a versatile alternative to the rotating disk electrode, reconciling well-defined hydrodynamics with operando access, automation, and – when coupled to gas-diffusion electrodes – industrially relevant current densities. Here, we discuss the principal flow-cell configurations by hydrodynamic regime, namely channel, impinging-jet (wall-tube and wall-jet), and mixed scanning flow cells, and analyze some representative practical examples in terms of the established mass-transport conditions and the operando and online techniques they enable.