The electrochemical synthesis of chemicals from carbon dioxide, which is an easily available and renewable carbon resource, is of great importance. However, to achieve high product selectivity for desirable C 2 products like ethylene is a big challenge.Here we design Cu nanosheets with nanoscaled defects (2−14 nm) for the electrochemical production of ethylene from carbon dioxide. A high ethylene Faradaic efficiency of 83.2% is achieved. It is proved that the nanoscaled defects can enrich the reaction intermediates and hydroxyl ions on the electrocatalyst, thus promoting C−C coupling for ethylene formation.

The activity of CoO for the electrocatalytic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid could be significantly enhanced by introducing oxygen vacancies via Se doping.