Thermochemical Reaction Triggered Formation of Surface Microstructures in Plasmonic Bubble Microreactors

Plasmonic microbubbles nucleated at liquid-immersed gold nanoparticles involve complex physicochemical hydrodynamics, enabling their widespread application across various fields. To date, research has primarily focused on the physical phenomena accompanying bubble nucleation, while the associated chemical processes remain less explored. In this study, a fascinating thermochemical reaction occurring within a growing plasmonic bubble in a ternary organic solution is reported. It is demonstrated that plasmonic bubbles can act as confined, localized high-temperature microreactors, where thermochemical reactions take place on vapor-phase organic molecules trapped inside the bubble. The reaction products are subsequently deposited onto the substrate within the laser-irradiated region, resulting in the formation of distinct surface microstructures. The morphology and dimensions of these structures can be well tuned by adjusting key control parameters. These findings not only highlight the potential of plasmonic microbubbles as controllable microreactors for localized thermochemical reactions but also present a novel method for surface microfabrication using continuous-wave lasers.