Image (IMAGE) Science China Press Caption (a) Cyclic voltammetry curves for CO2 reduction on carbon film electrode and metal-free carbon nanofibres (CNFs) electrode. (b) Absolute current density for CO2 reduction at different electrodes in pure [Emim]BF4 electrolyte. (c) Current density for CNFs catalyst with respect to H2O mole fraction (%) in [Emim]BF4. (d) Chronoamperogram for CNFs catalyst in pure [Emim]BF4. (e) Proposed schematic diagram for CO2 reduction mechanism. Credit �Science China Press Usage Restrictions Use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.