An Approach to Optimize the Composition of Supercapacitor Electrodes Consisting of Manganese-Molybdenum Mixed Oxide and Carbon Nanotubes

Abstract

We have fabricated composite electrode materials consisting of manganese-molybdenum mixed oxide and carbon nanotubes (CNTs) for supercapacitor application. The process involves electrophoretic deposition (EPD) of multi-walled CNTs onto an ITO electrode, followed by anodic deposition of Mn-Mo oxide from an aqueous Mn(II) solution containing MoO4 2− anions. Electrochemical properties of the composite electrodes with various combinations of Mn-Mo oxide and CNTs were evaluated systematically with the aim of maximizing the electrochemical utilization of the oxide. Optimization led to a high specific capacitance of 408 F g−1 at a scan rate of 2 mV s−1, with an area-normalized capacitance of 31 mF cm−2 (or a volume-normalized capacitance of 76 F cm−3).

Electrophoretic deposition of carbon nanotubes: recent progress and remaining challenges

“…Specific (pseudo)capacitance (F g −1 ) for different CNT-based composites deposited by EPD. Data obtained from Refs [60,92,97,98,110,139,141,144,188,196,[210][211][212]215].…”

Carbon fabric-aligned carbon nanotube/MnO2/conducting polymers ternary composite electrodes with high utilization and mass loading of MnO2 for super-capacitors

“…To overcome the limitation of each potential material, the design of specific composites prepared by the complementary combination of highly pseudocapacitive MnO 2 , conductive CNTs or flexible conducting polymers is regarded as a powerful candidate for outstanding electrode materials [17,18]. Based on this structure, many binary composites, such as MnO 2 /CNT [19e23] and MnO 2 / conducting polymers [24,25], have been studied for high electrochemical performances.…”

A Review on Nano-/Microstructured Materials Constructed by Electrochemical Technologies for Supercapacitors

“…These composites are typically electrodeposited through a one-step co-electrodeposition. The reported electrodeposited composites are classified according to their constituent species, including composites having the same group of materials, such as oxide/oxide (manganese oxide/molybdenum oxide [ 273 , 274 ], nickel manganese oxide [ 275 ], molybdenum oxide/tungsten oxide [ 276 ]), and composites with different types of materials, including oxide/conducting polymer (polypyrrole/manganese oxide [ 277 , 278 ], manganese oxide/polyaniline [ 279 , 280 ], manganese oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) [ 281 , 282 ], polyaniline/vanadium oxide [ 27 ], polypyrrole/vanadium oxide [ 283 , 284 ], polypyrrole/molybdenum oxide [ 285 ], polyaniline/tungsten oxide [ 286 ]) and oxide/hydroxide (NiAl-layered double hydroxide/manganese oxide [ 287 ] and manganese oxide/nickel hydroxide [ 288 ]). Their capacitance and corresponding synthesis methods are summarized in Table 2 .…”