title: Spray-Coated Multiwalled Carbon Nanotube Composite Electrodes for Thermal Energy Scavenging Electrochemical Cells.
abstract: Spray-coated multiwalled carbon nanotube/poly(vinylidene fluoride) (MWCNT/PVDF) composite electrodes, scCNTs, with varying CNT compositions (2 to 70 wt %) are presented for use in a simple thermal energy-scavenging cell (thermocell) based on the ferro/ferricyanide redox couple. Their utility for direct thermal-to-electrical energy conversion is explored at various temperature differentials and cell orientations. Performance is compared to that of buckypaper, a 100% CNT sheet material used as a benchmark electrode in thermocell research. The 30 to 70 wt % scCNT composites give the highest power output by electrode area-seven times greater than buckypaper at ΔT = 50 °C. CNT utilization is drastically enhanced in our electrodes, reaching 1 W gCNT(-1) compared to 0.036 W gCNT(-1) for buckypaper. Superior performance of our spray-coated electrodes is attributed to both wettability with better use of a large portion of electrochemically active CNTs and minimization of ohmic and thermal contact resistances. Even composites with as low as 2 wt % CNTs are still competitive with prior art. The MWCNT/PVDF composites developed herein are inexpensive, scalable, and serve a general need for CNT electrode optimization in next-generation devices.
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: Nicolas E
authors: NE
authors: Holubowitch
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: James
authors: J
authors: Landon
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: Cameron A
authors: CA
authors: Lippert
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: John D
authors: JD
authors: Craddock
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: Matthew C
authors: MC
authors: Weisenberger
authors: Center for Applied Energy Research, University of Kentucky , 2540 Research Park Drive, Lexington, Kentucky 40511, United States.
authors: Kunlei
authors: K
authors: Liu
keywords: Seebeck coefficient; carbon nanotube; energy scavenging; spray-coating; thermoelectrochemical cell