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Title: Low-temperature fabrication of morphology-controllable Cu2O for electrochemical CO2 reduction
Abstract

Cu2O has been successfully synthesized in different morphologies/sizes (nanoparticles and octahedrons) via a low-temperature chemical reduction method. Trapping metal ions in an ice cube and letting them slowly melt in a reducing agent solution is the simplest way to control the nanostructure. Enhancement of charge transfer and transportation of ions by Cu2O nanoparticles was shown by cyclic voltammetry and electrochemical impedance spectroscopy measurements. In addition, nanoparticles exhibited higher current densities, the lowest onset potential, and the Tafel slope than others. The Cu2O electrocatalyst (nanoparticles) demonstrated the Faraday efficiencies (FEs) of CO, CH4, and C2H6up to 11.90, 76.61, and 1.87%, respectively, at −0.30 V versus reference hydrogen electrode, which was relatively higher FEs than other morphologies/sizes. It is mainly attributed to nano-sized, more active sites and oxygen vacancy. In addition, it demonstrated stability over 11 h without any decay of current density. The mechanism related to morphology tuning and electrochemical CO2reduction reaction was explained. This work provides a possible way to fabricate the different morphologies/sizes of Cu2O at low-temperature chemical reduction methods for obtaining the CO, CH4,and C2H6products from CO2

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Award ID(s):
2100710
PAR ID:
10527002
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer Science + Business Media
Date Published:
Journal Name:
Journal of Materials Science
Volume:
59
Issue:
30
ISSN:
0022-2461
Format(s):
Medium: X Size: p. 13896-13907
Size(s):
p. 13896-13907
Sponsoring Org:
National Science Foundation
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