Theory in Practice: Testing the Limits of the Randles–Ševčík Equation

The Randles–Ševčík equation remains one of the most used equations in electrochemistry, and when used within its boundary conditions, it is an analytical solution for a 1-dimension diffusion problem. Despite being derived under strict and very clear boundary conditions, experiments rarely observe them or work within these limits. One of the more elusive boundary conditions is that diffusion must be one-dimensional, which in theory would require an infinitely large, “edgeless”, electrode. Here, we systematically test the limits of the Randles–Ševčík equation across a wide experimental parameter space by combining cyclic voltammetry and numerical simulations. We use an electrically conductive thermoplastic…

• FD
  Fundação de Amparo à Pesquisa do Estado de São Paulo

  Awards: 2021/00800-3, 2024/14586-1, 2025/00970-7
• CD
  Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

  Award: 33002010191P0