metal) systems have different electronic and crystalline
structure around the active sites or centers, which could
modulate the relative binding energy of different reaction
intermediates in the electrocatalytic surface and the local
atomic arrangement at the active sites. Moreover, the
change of the edge atoms in the bimetallic catalytic
systems may favor to improve CO2 adsorption on the
active sites and suppress the competitive the hydrogen
evolution reaction (HER). In the C-Sn-Zn catalytic system,
the synergic effect between Sn and Zn catalyst is
beneficial to improving the electrocatalytic reduction of
CO2 to selectively form CH3OH. Compared with C-Sn-Zn
catalyst, C-Py-Sn-Zn displays a higher FE of CH3OH
formation under the same electrolytic conditions (59.9%,
entry 4 and Fig. 4c). These results indicate that the
synergic effect between bimetallic Sn-Zn and 4-
aminopyridine (Py) could further enhance CO2
electroreduction to form CH3OH. In addition, the gaseous
products (CO and H2) could also be detected by using GC.
The presence of 4-aminopyridine may inhibit the
hydrogen evolution reaction (HER) because of 4-
aminopyridine containing alkaline groups.
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4. Conclusions
In summary, we have developed
a
novel
electrocatalyst C-Py-Sn-Zn by modifying carbon paper
electrode with bimetallic Sn-Zn and 4-aminopyridine.
This bifunctional heterogeneous catalyst could overcome
the inherent drawbacks of homogeneous catalysis. More
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Acknowledgments
This work was supported by the National Natural
Science Foundation of China (21572070) and the National
Key Research and Development Program of China
(2016YFA0602900).