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Abstract Plasmon-driven photocatalysis offers a unique means of leveraging nanoscale light–matter interactions to convert photon energy into chemical energy in a chemoselective and regioselective manner under mild reaction conditions. Plasmon-driven bond cleavage in molecular adsorbates represents a critical step in virtually all plasmon-mediated photocatalytic reactions and has been identified as the rate-determining step in many cases. This review article summarizes critical insights concerning plasmon-triggered bond-cleaving mechanisms gained through combined experimental and computational efforts over the past decade or so, elaborating on how the plasmon-derived physiochemical effects, metal–adsorbate interactions, and local chemical environments profoundly influence chemoselective bond-cleaving processes in a diverse set of molecular adsorbates ranging from small diatomic molecules to aliphatic and aromatic organic compounds. As demonstrated by several noteworthy examples, insights gained from fundamental mechanistic studies lay a critical knowledge foundation guiding rational design of nanoparticle–adsorbate systems with desired plasmonic molecule-scissoring functions for targeted applications, such as controlled release of molecular cargos, surface coating of solid-state materials, and selective bond activation for polymerization reactions.
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Utilizing light-triggered plasmon-driven catalysis reactions as a template for molecular delivery and release
Due to the facile manipulation and non-invasive nature of light-triggered release, it is one of the most potent ways to selectively and remotely deliver a molecular target. Among the various carrier platforms, plasmonic nanoparticles possess advantages such as enhanced cellular uptake and easy loading of “cargo” molecules. Two general strategies are currently utilized to achieve light-induced molecule release from plasmonic nanoparticles. The first uses femtosecond laser pulses to directly break the bond between the nanoparticle and the loaded target. The other requires significant photo-thermal effects to weaken the interaction between the cargo molecules and nanoparticle-attached host molecules. Different from above mechanisms, herein, we introduce a new light-controlled molecular-release method by taking advantage of a plasmon-driven catalytic reaction at the particle surface. In this strategy, we link the target to a plasmon responsive molecule, 4-aminobenzenethiol (4-ABT), through the robust and simple EDC coupling reaction and subsequently load the complex onto the particles via the strong Au–thiol interaction. Upon continuous-wave (CW) laser illumination, the excited surface plasmon catalyzes the formation of 4,4′-dimercaptoazobenzenethiol (DMAB) and simultaneously releases the loaded molecules with high efficiency. This method does not require the use of high-power pulsed lasers, nor does it rely on photo-thermal effects. We believe that plasmon-driven release strategies open a new direction for the designing of next-generation light-triggered release processes.
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- Award ID(s):
- 1709566
- PAR ID:
- 10057772
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 8
- Issue:
- 9
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 5902 to 5908
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C7SC02089A
