How do Bi nanoparticles restructure under CO2 reduction reaction conditions?
Beatriz Ávila-Bolívar, See Wee Chee, Beatriz Roldan Cuenya, and their colleagues at the University of Alicante and Fritz-Haber-Institut der Max-Planck-Gesellschaft published work using the Hummingbird Scientific Gen V In-situ Bulk Liquid-electrochemistry TEM sample holder to study the restructuring of Bi2O3 nanoparticles under electrochemical CO2 reduction conditions and reveal that pre-catalyst restructuring can occur due to the electrolyte environment and in the absence of applied potential.
a) Illustration of nanoparticle restructuring process. b) Time-lapse LC-TEM images collected with samples in contact with 0.1 M KHCO3 solution at open-circuit potential showing nanoparticle restructuring into nanosheets. c) Bismuth EDS map of nanosheets formed in (b). i) t=0 and ii) t=1 hr LC-TEM images and current density plots of the electrocatalysts after constant applied potentials of d) −0.3, e) −0.4, and f) −0.5 VRHE in CO2-saturated 1 M KHCO3 solution. Red arrows indicate nanosheet dissolution. Copyright © 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.
Time-lapse TEM images show that the nanoparticles transform into nanosheets when the electrolyte is changed from water to 0.1 M KHCO3 at open circuit conditions. The nanosheet agglomerates are stable at -0.3 VRHE but start dissolving at -0.4 and -0.5 VRHE. The restructuring was attributed to the solubility of Bi in the electrolyte, and indicates that nanoparticle-to-nanosheet conversion is intrinsic to CO2 reduction reaction conditions. Additional complementary experiments with operando Raman spectroscopy confirmed that oxide particles are reduced to metallic bismuth under applied potential, confirming that the metal particles are acting as the active phase for electrocatalytic formate production. The new insights into morphological changes to electrocatalysts due to applied potential will inform future catalyst design, synthesis, and pretreatment.
Reference:
Beatriz Ávila-Bolívar, Mauricio Lopez Luna, Fengli Yang, Aram Yoon, Vicente Montiel, José Solla-Gullón, See Wee Chee, and Beatriz Roldan Cuenya, ACS Appl. Mater. Interfaces 16 (9) 11552-11560 (2024) DOI: 10.1021/acsami.3c18285
Full paper Copyright © 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.
View All News