TY - JOUR
T1 - Electrochemical fabrication of carbon fiber-based nickel hydroxide/carbon nanotube composite electrodes for improved electro-oxidation of the urea present in alkaline solutions
AU - Liu, Yi Hung
AU - Hung, Chi Han
AU - Hsu, Cheng Liang
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/3/1
Y1 - 2021/3/1
N2 - A Ni(OH)2/carbon nanotube (CNT)/carbon fiber (CF) composite electrode was developed, and its electrode kinetics was investigated to improve its urea oxidation reaction (UOR) performance. The fabrication of the electrode was done using electrophoretic co-deposition combined with hydrothermal reaction. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy were used to examine the electrode properties, while cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) were used to study the electrode kinetics. The prepared catalyst that had a flake-like structure was an α phase Ni(OH)2 catalyst, which mixed well with the CNTs to form a composite layer on the CF substrate. The α-Ni(OH)2/CNT/CF electrode displayed satisfactory UOR performance because it had a higher oxidation current and a lower overpotential than those of either the α-Ni(OH)2/CF electrode or CF electrode. These improved properties of the α-Ni(OH)2/CNT/CF electrode can be because of the active and reversible Ni2+/Ni3+ redox reaction, which has high rate constant and anodic transfer coefficient, of the α-Ni(OH)2/CNT composite. Moreover, compared with α-Ni(OH)2/CF or CF electrodes, the α-Ni(OH)2/CNT/CF electrode has a low charge transfer resistance because of the increase in the reaction surface area and electrical conductivity caused by the CNTs. Overall, the composite electrode combines the advantages of the α-Ni(OH)2 catalyst, CNT conductive network, and CF current collector for improved UOR performance, which will be beneficial for urea pollution mitigation and H2 production.
AB - A Ni(OH)2/carbon nanotube (CNT)/carbon fiber (CF) composite electrode was developed, and its electrode kinetics was investigated to improve its urea oxidation reaction (UOR) performance. The fabrication of the electrode was done using electrophoretic co-deposition combined with hydrothermal reaction. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy were used to examine the electrode properties, while cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) were used to study the electrode kinetics. The prepared catalyst that had a flake-like structure was an α phase Ni(OH)2 catalyst, which mixed well with the CNTs to form a composite layer on the CF substrate. The α-Ni(OH)2/CNT/CF electrode displayed satisfactory UOR performance because it had a higher oxidation current and a lower overpotential than those of either the α-Ni(OH)2/CF electrode or CF electrode. These improved properties of the α-Ni(OH)2/CNT/CF electrode can be because of the active and reversible Ni2+/Ni3+ redox reaction, which has high rate constant and anodic transfer coefficient, of the α-Ni(OH)2/CNT composite. Moreover, compared with α-Ni(OH)2/CF or CF electrodes, the α-Ni(OH)2/CNT/CF electrode has a low charge transfer resistance because of the increase in the reaction surface area and electrical conductivity caused by the CNTs. Overall, the composite electrode combines the advantages of the α-Ni(OH)2 catalyst, CNT conductive network, and CF current collector for improved UOR performance, which will be beneficial for urea pollution mitigation and H2 production.
KW - Carbon fiber
KW - Carbon nanotube
KW - Composite
KW - Nickel hydroxide
KW - Urea oxidation reaction
UR - http://www.scopus.com/inward/record.url?scp=85096223114&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2020.118002
DO - 10.1016/j.seppur.2020.118002
M3 - 期刊論文
AN - SCOPUS:85096223114
SN - 1383-5866
VL - 258
JO - Separation and Purification Technology
JF - Separation and Purification Technology
M1 - 118002
ER -