cs8b00726_si_001.pdf (1.65 MB)
Why Could the Nature of Surface Facets Lead to Differences in the Activity and Stability of Cu2O‑Based Electrocatalytic Sensors?
journal contribution
posted on 2018-06-04, 00:00 authored by Fabián A. C. Pastrián, Anderson G. M. da Silva, André H.
B. Dourado, Ana P. de Lima Batista, Antonio G. S. de Oliveira-Filho, Jhon Quiroz, Daniela C. de Oliveira, Pedro H. C. Camargo, Susana I. Córdoba de TorresiBy a combination of theoretical and
experimental design, we unraveled the effect of {111} and {100} surface
facets on the electrocatalytic sensing activities and stabilities
of metal oxides by employing Cu2O crystals as a model substrate
and glucose as the analyte. We started by theoretically investigating
the potential energy curves for the glucose interaction with the Cu2O {111} and {100} surface facets. We found that the glucose
interaction energy was significantly higher for the {100} facets than
for the {111} facets. Then, we experimentally observed that their
electrocatalytic sensing performance displayed shape-dependent behavior.
While the catalytic activities followed the order cubes > cuboctahedrons
> octahedrons, their stabilities showed the opposite trend. The
higher catalytic activity enabled by the {100} facets is explained
by their stronger interaction with glucose. On the other hand, the
higher stability allowed by the {111} facets is justified by their
lower concentration of oxygen vacancies and weaker interaction with
O2 relative to those of the {100} surface.