# Laser writing of plasmonic catalytic microchannels on UiO-66 layer

## TL;DR

A new laser method creates plasmonic microchannels with gold nanoparticles on recycled plastic, enabling efficient and scalable solar-to-chemical energy systems.

## Contribution

A one-step laser method for forming gold nanoparticles and patterning microchannels on MOF-functionalized PET substrates is introduced.

## Key findings

- Laser-induced in situ reduction of HAuCl4 forms ≈5.4 nm gold nanoparticles within a UiO-66 matrix on PET.
- The resulting PET@Au composites show plasmon resonance at 550 nm and catalytic activity for methylene blue degradation under visible light.
- The method uses low-cost materials and sustainable processing for scalable microfluidic and photocatalytic devices.

## Abstract

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.

Plasmonic microchannels are patterned by laser-induced in situ Au NPs reduction on MOF-functionalized PET for reducing fabrication steps and costs towards plasmon-active microfluidic chips design.