Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels

Abstract

Large-scale utilization of solar-energy resources will require considerable advances in energy-storage technologies to meet ever-increasing global energy demands. Other than liquid fuels, existing energy-storage materials do not provide the requisite combination of high energy density, high stability, easy handling, transportability and low cost. New hybrid solar thermal fuels, composed of photoswitchable molecules on rigid, low-mass nanostructures, transcend the physical limitations of molecular solar thermal fuels by introducing local sterically constrained environments in which interactions between chromophores can be tuned. We demonstrate this principle of a hybrid solar thermal fuel using azobenzene-functionalized carbon nanotubes. We show that, on composite bundling, the amount of energy stored per azobenzene more than doubles from 58 to 120 kJ mol(-1), and the material also maintains robust cyclability and stability. Our results demonstrate that solar thermal fuels composed of molecule-nanostructure hybrids can exhibit significantly enhanced energy-storage capabilities through the generation of template-enforced steric strain.

Reversible solvatomagnetic switching in a single-ion magnet from an entatic state

“…Recently, the entatic state concept has also been indirectly used for “local sterically constrained environments” to improve new hybrid solar thermal fuels through the preservation of the robust cyclability and stability of the material. 37 …”

Phonon Conduction in Silicon Nanobeam Labyrinths

“…Understanding phonon transport is crucial to engineering novel nanoscale systems, such as thermal energy storage 1–3 , heat-assisted memory 4, 5 , sensors 6, 7 , and integrated nanoelectronics 8, 9 . Previous studies of phonons in single crystalline silicon have established an increasingly comprehensive microscopic model of how phonons interact with introduced nanoscale features and boundaries 10 .…”

Photon energy storage materials with high energy densities based on diacetylene–azobenzene derivatives

“…14 Therefore, strategies to increase the energy storage in azobenzene derivatives have been investigated by both computation and experiments, with one effective method shown to be the anchoring of photochromic molecules to rigid templates such as carbon nanotubes, graphene, and other hydrocarbons, [15][16][17][18][19][20] which takes advantage of the relative strength of intermolecular interactions in the closepacked trans and cis isomers. Even without the templates, we expect that the intermolecular interactions such as H-bonding, van der Waals force, and p-p interaction can signicantly inuence the photon energy storage density.…”