Operando studies reveal active Cu nanograins for CO₂ electroreduction

Journal Article · Wed Feb 08 00:00:00 UTC 2023 · Nature (London)

DOI:https://doi.org/10.1038/s41586-022-05540-0· OSTI ID:2293522

Yang, Yao ^[1]; Louisia, Sheena ^[1]; Yu, Sunmoon ^[2]; Jin, Jianbo ^[3]; Roh, Inwhan ^[1]; Chen, Chubai ^[1]; Fonseca Guzman, Maria V. ^[1]; Feijóo, Julian ^[1]; Chen, Peng-Cheng ^[4]; Wang, Hongsen ^[5]; Pollock, Christopher J. ^[6]; Huang, Xin ^[6]; Shao, Yu-Tsun ^[5]; Wang, Cheng ^[7]; Muller, David A. ^[5]; Abruña, Héctor D. ^[5]; Yang, Peidong ^[8]

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1. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
2. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
3. Univ. of California, Berkeley, CA (United States)
4. Univ. of California, Berkeley, CA (United States); Kavli Energy NanoScience Institute, Berkeley, CA (United States)
5. Cornell Univ., Ithaca, NY (United States)
6. Cornell Univ., Ithaca, NY (United States). Cornell High Energy Synchrotron Source (CHESS)
7. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
8. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Kavli Energy NanoScience Institute, Berkeley, CA (United States)

Carbon dioxide electroreduction facilitates the sustainable synthesis of fuels and chemicals. Although Cu enables CO₂-to-multicarbon product (C₂₊) conversion, the nature of the active sites under operating conditions remains elusive. Importantly, identifying active sites of high-performance Cu nanocatalysts necessitates nanoscale, time-resolved operando techniques. Here, we present a comprehensive investigation of the structural dynamics during the life cycle of Cu nanocatalysts. A 7 nm Cu nanoparticle ensemble evolves into metallic Cu nanograins during electrolysis before complete oxidation to single-crystal Cu₂O nanocubes following post-electrolysis air exposure. Operando analytical and four-dimensional electrochemical liquid-cell scanning transmission electron microscopy shows the presence of metallic Cu nanograins under CO₂ reduction conditions. Correlated high-energy-resolution time-resolved X-ray spectroscopy suggests that metallic Cu, rich in nanograin boundaries, supports undercoordinated active sites for C–C coupling. Quantitative structure–activity correlation shows that a higher fraction of metallic Cu nanograins leads to higher C₂₊ selectivity. A 7 nm Cu nanoparticle ensemble, with a unity fraction of active Cu nanograins, exhibits sixfold higher C₂₊ selectivity than the 18 nm counterpart with one-third of active Cu nanograins. Importantly, the correlation of multimodal operando techniques serves as a powerful platform to advance our fundamental understanding of the complex structural evolution of nanocatalysts under electrochemical conditions.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
• Grant/Contract Number: AC02-05CH11231; SC0019445
• OSTI ID: 2293522
• Journal Information: Nature (London), Journal Name: Nature (London) Vol. 614; ISSN 0028-0836
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
electrochemistry
energy