Photoliquefiable Azobenzene Surfactants toward Solar Thermal Fuels that Upgrade Photon Energy Storage via Molecular Design

Abstract

In recent years, azobenzene-containing materials for photon energy storage are gaining increasing attentions. [2][3][4][5][6][7][8] To compensate the insufficient energy density of pristine azobenzene (41 kJ mol −1 ), [9] several strategies have been designed, e.g., tethering azobenzene to rigid carbon template. [10][11][12][13][14] Although with improved energy density, such materials normally require solution state for energy charging. That is because the high packing density in solid state makes trans-to-cis isomerization difficult. And as a consequence, the photoresponsive solid-to-liquid phase change used for latent heat storage becomes impossible for such materials.

Optimizing the performance of phase-change azobenzene: from trial and error to machine learning

“…3D isosurfaces illustrating the (b) Azo, (c) Azo-1, and (d) Azo-2 dimers generated using the IGMH method. 144 Copyright 2023, Wiley.…”

“…The competitive mechanisms of ''cation-p'' interactions and ''p-p stacking'' not only weaken the energy barrier but also reduce the high molar extinction efficiency. Zhang et al 144 prepared two PC-Azo derivatives incorporating distinct R-rings onto the ammonium head of surfactants, along with linear tail chains and spacer chains, as depicted in Fig. 16a.…”

Regulatable interfacial adhesion between stamp and ink for transfer printing

“…For example, azobenzene compounds possess the photoswitchable reversible solid–liquid transition induced by isomerization, [ 130 ] which have shown applications in photoactuators, [ 131 ] gas separation, [ 132 ] and solar thermal fuels. [ 133 ] Zhou et al synthesized azobenzene‐containing polymers (azopolymers) with photoswitchable T g through reversible addition‐fragmentation chain‐transfer (Figure 10A). [ 90 ] These azopolymers can transition from solid‐to‐liquid state under UV irradiation due to the decrease of T g induced by trans – cis isomerization.…”

Visible-Light Responsive Azobenzene and Cholesterol Based Liquid Crystals as Efficient Solid-State Solar–Thermal Fuels

“…We also evaluated the energy densities of the compounds 7b−7d in cis PSS by DSC as reported earlier (SI, Table S3, Figure S24). 28 The maximum value was observed for 7b (94.12 kJ/mol).…”