Dr. Mikhail Koralev, working with other members of the eCO2EP project team in the CREATE labs in Singapore, has discovered that flooding of gas diffusion electrodes (GDEs) used in electrochemical conversion of CO₂ to ethylene is caused by polymerization of minor products. The polymer so created reduces the hydrophobicity of the GDE, leading initially to a reduction in the ethylene yield and finally to complete failure. The work has been published as an Express Letter in ACS Energy Letters.