jp7b09758_si_001.pdf (1.21 MB)
Deciphering the Electrocatalytic Activity of Nitrogen-Doped Carbon Embedded with Cobalt Nanoparticles and the Reaction Mechanism of Triiodide Reduction in Dye-Sensitized Solar Cells
journal contribution
posted on 2017-11-27, 00:00 authored by Sung Hee Ahn, Chi Ho Lee, Min Soo Kim, Seul Ah Kim, Byungwuk Kang, Hee-eun Kim, Sang Uck Lee, Jin Ho BangThe
electrocatalytic activity of carbon materials for triiodide
(I3–) reduction has spurred the development
of low-cost electrocatalysts as an alternative to platinum in dye-sensitized
solar cells. While many catalytic aspects of nitrogen-doped carbons
have been unveiled in recent years, not all underlying factors that
dictate their electrocatalytic activity have been fully considered;
the current understanding of the electrocatalytic activity of nitrogen-doped
carbons is limited. In addition, the synergistic effect of metal nanoparticles
embedded in nitrogen-doped carbon, which was recently demonstrated
as a facile way to boost the electrocatalytic activity of carbon,
remains elusive. This work sheds light on these unknown aspects of
carbon’s electrocatalytic activity by carrying out a systematic
investigation of nitrogen-doped carbon with incorporated cobalt nanoparticles.
Furthermore, the generally accepted mechanism of the I3– reduction reaction (IRR) is re-evaluated in this
work with the aid of density functional theory calculations and in-depth
electrochemical analysis. A new insight into this mechanism, which
suggests that there is another possible reaction pathway available
for the IRR on carbon, is provided.