A total of 15 ionic, reactant and product species are modelled in this work. To reduce computational cost and mitigate the risk of encountering convergence problems, in addition to six species from the side bicarbonate reactions in the catholyte (CO2, H + , 𝑂𝐻 -, K + , 𝐶𝑂 3 2-, 𝐻𝐶𝑂 3 -), we explore only on 9 CO2RR products with substantial current densities, as shown in Table . The catholyte and its concentration is 0.1 M KHCO3. Physical parameters of the GDE and physical properties of the participating species enumerated in Table are given in Tables and in the Supporting Information.