Chemically functionalized graphene/polymer nanocomposites as light heating platform

Chemically functionalized graphene (CFG) is proposed as a novel nanoscale optical heater by uniformly dispersing it in poly(dimethylsiloxane) (PDMS) matrix. And subsequently, a simple, fast, and localized heating method on microfluidic chips is demonstrated. CFG is prepared through simultaneous modification and reduction of graphene oxide with dodecylamine by a solvothermal route. It is well dispersed in PDMS suspension to form uniform CFG/PDMS composite due to the presence of the long-dodecyl chain. The obtained CFG/PDMS composites are readily made into microfluidic chips by standard soft lithography. The localized optical heating on the chip is realized by employing a conventional semiconductor laser as light source. The prepared chips with low to 0.05 wt% CFG contents can exhibit temperature increase (<1 min) at very low power illumination. The optical heating effects were observed not only under irradiation with long wavelength, but also under the wavelengths as short as 405 nm. Our studies illustrated that CFG/PDMS composite can serve as a practical optical heating platform for microfluidic chips with the advantages of simple, low cost, and high efficiency. POLYM. COMPOS., 37:1350–1358, 2016. © 2014 Society of Plastics Engineers