ChemSusChem
10.1002/cssc.201801612
COMMUNICATION
electro-reduction. In
measurements of all catalysts were investigated at 298K (Figure
b). For AgNWs/NC700, the CO adsorption capacity at 298 K
our
research,
CO
2
adsorption
The financial support of the National Natural Science Foundation
(NNSF) of China (21574084 and 21571131), the Natural
Science Foundation of Guangdong Province (2015A030313554
and 2017A040405066), and Shenzhen Government’s Plan of
5
2
3
-1
3
-1
and 1 atm is 59.1 cm g STP, lager than 50.6 cm g STP for
3
-1
AgNWs/NC800 and 43.1 cm g STP for AgNWs/NC600. Pure
Science
and
Technology
(JCYJ20160308104704791,
3
-1
2
AgNWs almost have no ability to adsorb CO (0.61 cm g STP),
JCYJ20170817095041212 and JCYJ20170818091657056) are
gratefully acknowledged.
compared to AgNWs/NC. Moreover, the specific surface areas
and total pore volume of AgNWs/NC600, 700 and 800 are very
close (Figure S12 and Table S4). Therefore, the differences in
Keywords: Core-shell structure • CO
2
fixation • Electrochemical
adsorption
2
CO adsorption capacity might be related to the chemical
catalysis • multifunctional catalyst • CO
2
composition of different catalysts, such as the nitrogen amount
and atomic configuration. To investigate these effects, density
functional theory (DFT) studies were performed using DMol3
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code (details in SI). The adsorption energies (ΔEads) of CO
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2
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to the surface of silver core, which is the
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1
AgNWs/NC700 could be attributed to relatively higher CO
concentration around AgNWs created by N-doped carbon shell.
In conclusion, we have firstly demonstrated the core-shell
structured AgNWs/NC700 composite as a multifunctional and
2
2
2
highly efficient electro-catalyst for CO
coating of N-doped carbon shell could increase CO
capacity, creating a CO -rich environment around AgNWs core
inset of Figure 5c), and then significantly enhance the catalytic
activity for electrochemical CO fixation in aqueous and organic
system. This work might offer positive inspirations for designing
2
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