Composition-Controlled Cu/Cu3N Nanoparticles via Cylindrical Magnetron Sputtering for Multicarbon CO2 Electroreduction
Year: 2026
Type: article
Abstract: Electrochemical CO2 reduction (eCO2R) represents an important strategy to mitigate CO2 emissions while yielding value-added multicarbon (C2+) products, such as ethylene and ethanol. Copper nitride (Cu3N) nanoparticles (NPs) have emerged as attractive catalysts for eCO2R; however, their synthesis remains challenging and is typically limited to multistep liquid phase methods. This work demonstrates an efficient gas-phase approach for the compositional and structural tuning of Cu3N-based NPs by using cylindrical magnetron reactive sputtering with controlled N2/Ar gas mixtures. By varying nitrogen incorporation, the NPs exhibit a controlled transition from metallic Cu to biphasic Cu/Cu3N and ultimately to stoichiometric Cu3N, while maintaining a nearly constant NP size (20–27 nm). Structural characterization combining HR-TEM, Doppler broadening variable-energy positron annihilation spectroscopy (DB-VEPAS), and variable-energy positron annihilation lifetime spectroscopy (VEPALS) reveals a progressive increase in structural defects with nitrogen incorporation, including vacancy clusters, subnanometer voids, mesopores, and nanometer-sized internal voids. The defect-rich Cu3N NPs exhibit the highest concentration of vacancy-type defects and the most pronounced internal porosities. Electrochemical measurements demonstrate that these NPs are active eCO2R catalysts for C2+ product formation, with Cu3N outperforming both metallic Cu and biphasic Cu/Cu3N in terms of the Faradaic efficiency (FE), achieving 50% for C2H4 and 20% for C2H5OH. Cu3N NPs also yield a narrower C2+ product distribution with an overall FE of 79%. These results establish reactively sputtered Cu3N-based NPs as a tunable catalyst platform in which composition, structure, and morphology govern eCO2R selectivity and efficiency.
Source: ACS Applied Nano Materials
Authors: Ronaldo Katuta, Veronika Červenková, Daniil Nikitin, Jan Hanuš, Iqra Wahid, Suren Ali-Ogly, Kateřina Škorvánková, Pavel Mareš, Jiří Vyskočil, Miroslav Cieslar, Lucia Bajtošová, Milan Dopita, Tereza Košutová, Eric Hirschmann, Maciej Oskar Liedke, Andreas Wagner, Mathias van der Veer, Nick Daems, Tom Breugelmans, Caroline Adam, Holger Kersten, Andrei Choukourov, Hynek Biederman
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
OpenAlex ID: W7204777788