Laser writing of plasmonic catalytic microchannels on UiO-66 layer

Plasmon-assisted catalysis offers an attractive route for solar-to-chemical energy conversion, yet its practical integration into scalable flow systems remains limited by complex fabrication steps and poor nanoparticle stability. Here, we report a one-step laser-assisted method for simultaneously forming gold nanoparticles (Au NPs) and patterning microchannels on metal-organic framework (MOF)-functionalized polyethylene terephthalate (PET) substrates derived from waste plastic. Using a 405 nm laser, the in situ reduction of HAuCl₄ within a UiO-66 matrix deposited on PET enables homogeneous Au NPs formation (≈5.4 nm) and precise microchannel definition without the need for additional reagents or post-processing. The resulting PET@Au composites exhibit strong plasmon resonance at 550 nm and catalytic activity for the degradation of methylene blue under visible light, confirming their functional performance. This approach combines plasmonic functionality, low-cost materials, and sustainable processing into a scalable platform for the development of integrated microfluidic and photocatalytic devices.