Electrochemical Fabrication and Reactivation of NanoporousGold with Abundant Surface Steps for CO 2 Reduction
2020
Distinct
from bulk materials, dealloyed nanoporous metals possess
a large electrochemical surface area and abundant surface steps that
are active for electrochemical reactions. Herein we fabricate a nanoporous
gold electrocatalyst by electrochemical dealloying of potential cycling,
which enables reducing carbon dioxide to carbon monoxide with a Faradaic
efficiency of up to 98% at an overpotential of 390 mV. Pb-upd measurements
verify that the high activity stems from the high density of step/kink
sites with geometrically needed high-index facets on the curved internal
surface. Moreover, a combination of X-ray photoelectron spectroscopy
and in situ stripping voltammograms reveals that
catalysis decay during long-term stability test results from the reduction
of surface step/kink sites and the deposition of metal impurities
(Zn, Pb, and Cu). The catalytic performance of the deactivated electrode
can be recovered by applying potential cycling, which can restore
the fractions of step/kink sites and remove surface metal impurities
simultaneously.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
78
References
10
Citations
NaN
KQI