title: Chemically driven carbon-nanotube-guided thermopower waves.
abstract: Theoretical calculations predict that by coupling an exothermic chemical reaction with a nanotube or nanowire possessing a high axial thermal conductivity, a self-propagating reactive wave can be driven along its length. Herein, such waves are realized using a 7-nm cyclotrimethylene trinitramine annular shell around a multiwalled carbon nanotube and are amplified by more than 10(4) times the bulk value, propagating faster than 2 m s(-1), with an effective thermal conductivity of 1.28+/-0.2 kW m(-1) K(-1) at 2,860 K. This wave produces a concomitant electrical pulse of disproportionately high specific power, as large as 7 kW kg(-1), which we identify as a thermopower wave. Thermally excited carriers flow in the direction of the propagating reaction with a specific power that scales inversely with system size. The reaction also evolves an anisotropic pressure wave of high total impulse per mass (300 N s kg(-1)). Such waves of high power density may find uses as unique energy sources.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA.
authors.forename: Wonjoon
authors.initials: W
authors.lastname: Choi
authors.forename: Seunghyun
authors.initials: S
authors.lastname: Hong
authors.forename: Joel T
authors.initials: JT
authors.lastname: Abrahamson
authors.forename: Jae-Hee
authors.initials: JH
authors.lastname: Han
authors.forename: Changsik
authors.initials: C
authors.lastname: Song
authors.forename: Nitish
authors.initials: N
authors.lastname: Nair
authors.forename: Seunghyun
authors.initials: S
authors.lastname: Baik
authors.forename: Michael S
authors.initials: MS
authors.lastname: Strano