Lattice Boltzmann simulations of electrolysis reactions: Microfluidic voltammetry

A lattice Boltzmann model was used to simulate electrolysis reactions occurring within reactors where fluid is pumped through the device under microfluidic control. This article describes the application of two- and three-dimensional procedures for the simulation of the fluid velocities and mass transport characteristics within reactors of an arbitrary geometry. The lattice Boltzmann method is used to simulate the mass transport limited reduction of a species at a large planar electrode, embedded within one wall of a rectangular duct, under either steady-state or potential step conditions. The results of the simulations are compared to both those predicted analytically and via Finite Difference methods for this geometry and used to assess the accuracy of the approach. Good agreement is found between the lattice Boltzmann models and the well-established analytical theory, highlighting the potential of this approach for electrochemical applications within microfluidic environments. A major benefit of the lattice Boltzmann approach is the simple extension of the method to more complex cell and electrode geometries; the potential benefits of this are also noted.