Optical absorption spectrum of (a) poly(9,9-dioctylfluorene, 2,7-diyl) (PFO) wrapped highly mono-dispersed (7, 5) film (red solid) and simulated/fit optical absorption spectrum of pure (7, 5) film (blue dash) and (b) Bundles of highly mono-dispersed (6, 5) nanotubes (red solid) and simulated optical absorption spectrum of pure (6, 5) film (blue dash).
AM1.5G solar spectrum (black solid); optical transitions at energies S 1 (red circles); S 2 (blue triangles), and S 3 (green squares). 32–35
Schematic illustrating hexagonally packed nanotube fiber morphology and possible intra- and inter-nanotube routes for exciton migration.
AM1.5G solar spectrum (grey solid) and optimized natural absorption spectrum with mixture of chiralities in strongly coupled film (red solid) and polymer wrapped nanotubes film (blue dash). Mixture of chiralities are (5, 4) 7.8%, (6, 4) 15.6%, (6, 5) 4.7%, (7, 2) 18.7%, (7, 3) 5.7%, (8, 1) 24.9%, (8, 3) 6.4%, (9, 1) 8.4%, and (11, 0) 7.8%.
Spatial distribution of 1000 excitons in (a) x-direction (within the cross-section of the fiber) and strong coupling, (b) z-direction (along the length of the fiber) and strong coupling, (c) x-direction and moderate coupling, and (d) z-direction and moderate coupling, at 10 fs (black up triangles), 100 fs (red down triangles), 1 ps (blue diamonds), and 10 ps (green left triangles). (e) Kurtosis as a function of time in strong (black squares) and moderate coupling (red circles). (f) Kurtosis as a function of relative concentration of the (7, 5) and the (9, 7) nanotubes after 10 ps.
Evolution of exciton population in mixtures of (7, 5) (black solid), (7, 6) (red dash), (8, 6) (green dot), (8, 7) (blue dash dot), and (9, 7) (wine short dot) chiralities at a ratio of 0.16: 0.22: 0.29: 0.25: 0.08, respectively, as a function of time following photoexcitation of a (7, 5) nanotube in (a) strong and (b) moderate coupling.
Photoluminescence spectra of isolated and coupled nanotubes. Isolated nanotubes in solution (blue dot) and embedded in poly(methyl methacrylate) (PMMA) at a 1000:1 ratio of PMMA:nanotubes by weight (red solid). Coupled nanotubes at a 1:1 ratio of PFO:nanotubes by weight (black dash). Excitation at 658 nm (corresponding to the S 2 of the (7, 5) and (7, 6) nanotubes). Isolated and coupled nanotube spectra normalized at 1050 and 1330 nm, respectively.
Effects of polydispersity. (a) Radial exciton diffusion length as a function of the relative concentration of the (7, 5) and the (9, 7) nanotubes in strong coupling after 10 ps. (b) Evolution of exciton population with a ratio of 92%:8% of (7, 5) (blue dash) to (9, 7) (red solid).
The characteristic radial distance LD across which an exciton migrates in a fiber of strong coupled (7, 5) semiconducting nanotubes until that exciton is quenched by a spurious metallic nanotube, as a function of the relative abundance of metallic nanotubes.
The characteristic radial distance LD across which an exciton migrates in a fiber of (7, 5) semiconducting nanotubes until that exciton is quenched by a defect, as a function of defect concentration in strong (black squares) and moderate (red triangles) coupling.
Schematic illustrating nanotube fiber morphology in a bilayered nanotube/acceptor heterojunction. μP , LF , and t denote the characteristic out-of-plane component of the orientation of a fiber, the fiber diameter, and the thickness of the nanotube layer, respectively.
Radial exciton diffusion length (LD ) and thin film absorption length ( ) in nm as a function of chiral composition (%), assuming 100% semiconducting purity, λ = 500 nm, and strong coupling.
Article metrics loading...
Full text loading...