Melchionna, MicheleCriado, AlejandroBonchio, MarcellaFornasiero, PaoloPaolucci, FrancescoPrato, Maurizio2024-08-072024-08-072020-08-19ACS Appl. Energy Mater. 2020, 3, 9, 8509–85182574-0962 (eISSN)http://hdl.handle.net/2183/38440[Abstract]: The combination of multiwalled carbon nanotubes (MWCNTs) with undoped CeO2 na-noparticles (NPs) is effective for the direct electrocatalytic reduction of CO2 to formic acid (FA) at acidic pH (0.1 M HNO3), at overpotential as low as η = −0.02 V (vs RHE) with Faradic efficiency (FE) up to 65%. Exsitu and operando evidence identifies nons-toichiometric Ce4+/3+O2–x reduced sites as essential for the selective CO2 reduction reac-tion (CO2RR). The MWCNT-mediated electrochemical reduction of the CeO2 NPs of-fers a definite advantage with respect to the generally adopted thermochemical cycles (800–1500 °C) or deep hydrogenation pretreatments, thus presenting an interesting perspective for the engineering of CeO2 electrocatalysts.engCopyright © 2020 American Chemical Society. This is an open access article published under an ACS AuthorChoice License (https://pubs.acs.org/page/policy/authorchoice_termsofuse.html), which permits copying and redistribution of the article or any adaptations for non-commercial purposes.Carbon nanotubesCerium oxideCarbon dioxide reductionElectrocatalytic hydrogenationMetal oxide electrocatalystsjournal articleopen access10.1021/acsaem.0c01145