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Self-regulating photochemical Rayleigh-Benard convection using a highly-absorbing organic photoswitch.

ABSTRACT: We identify unique features of a highly-absorbing negatively photochromic molecular switch, donor acceptor Stenhouse adduct (DASA), that enable its use for self-regulating light-activated control of fluid flow. Leveraging features of DASA's chemical properties and solvent-dependent reaction kinetics, we demonstrate its use for photo-controlled Rayleigh-Bénard convection to generate dynamic, self-regulating flows with unparalleled fluid velocities (~mm s-1) simply by illuminating the fluid with visible light. The exceptional absorbance of DASAs in solution, uniquely controllable reaction kinetics and resulting spatially-confined photothermal flows demonstrate the ways in which photoswitches present exciting opportunities for their use in optofluidics applications requiring tunable flow behavior.

SUBMITTER: Seshadri S

PROVIDER: S-EPMC7248117 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Self-regulating photochemical Rayleigh-Bénard convection using a highly-absorbing organic photoswitch.

Seshadri Serena S Gockowski Luke F LF Lee Jaejun J Sroda Miranda M Helgeson Matthew E ME Read de Alaniz Javier J Valentine Megan T MT

Nature communications 20200525 1

We identify unique features of a highly-absorbing negatively photochromic molecular switch, donor acceptor Stenhouse adduct (DASA), that enable its use for self-regulating light-activated control of fluid flow. Leveraging features of DASA's chemical properties and solvent-dependent reaction kinetics, we demonstrate its use for photo-controlled Rayleigh-Bénard convection to generate dynamic, self-regulating flows with unparalleled fluid velocities (~mm s<sup>-1</sup>) simply by illuminating the f ...[more]

PMID: 32451397

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