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Title: Electrocatalytic CO 2 Reduction at Pyridine Functionalized Au Nanoparticles Supported by NanoCOT Electrode
CO 2 reduction reaction (CO 2 RR) is a promising technique for mitigating global warming and storing renewable energy if it can be obtained with a highly selective, efficient, and durable electrocatalyst. Here, we report CO 2 RR catalyzed by Au nanoparticles (NPs) stabilized by pyridines and pyrimidines (e.g., 2-mercaptopyridine (2Mpy), 4-mercaptopyridine (4Mpy), and 2-mercaptopyrimidine (2Mpym)) on a nanostructured carbon-doped TiO 2 nanowire (NanoCOT) electrode, which has been previously reported by our team for electrocatalytic water oxidation. An online gas chromatography (GC) set-up with improved gaseous product sensitivity with real-time pressure monitoring is used to quantify CO and hydrogen products from the Au NP-modified NanoCOT electrode. High CO selectivity is observed at Au-2Mpy coated NanoCOT electrode. CO 2 reduction products are not observed at bare NanoCOT suggesting CO 2 is reduced at the Au nanoparticle sites of the electrode. Moreover, CH 3 OH is not detected at the Au-Mpy/Mpym NPs during rotating ring disk electrode (RRDE) analysis which implies pyridine attached to the Au NPs has no catalytic effects on CO 2 RR as claimed by others in the literature. A durable complete H-cell using a NanoCOT anode and Au NP-NanoCOT cathode electrodes is assembled for complete water splitting, CO 2 RR, and stability test.  more » « less
Award ID(s):
2113505
PAR ID:
10397193
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
169
Issue:
11
ISSN:
0013-4651
Page Range / eLocation ID:
116510
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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