利用近红外光在微纳光纤传输时产生的强烈倏逝场效应将氧化石墨烯沉积在微纳光纤表面,组装成具有优异光热转换性能的氧化石墨烯一微纳光纤,得到一种新型的光驱动微加热器.通入较小功率的近红外光,微加热器能诱导各种液体(例如N,N-二甲基甲酰胺、去离子水)产生高温相变进而产生微泡,显示了良好的光热转换效应.结果表明,在N,N-二甲基甲酰胺中,微泡按一定周期循环生长,重复搅动液体.在微流芯片中,这些微泡可用于操控微纳米颗粒、微纳米线等.在去离子水中,产生的微泡结构稳定、不易破裂,可用于聚集微粒等.该微加热器具有制备简单、尺寸小、损耗低、激发功率小、效率高等优良特性,在微机电系统、微流控芯片等领域具有良好的应用前景.
An optical technique is developed by depositing graphene oxide (GO) onto a micro/nanofiber (MNF), which can act as a novel light-driven microheater based on the strong evanescent field from MNF and the photothermal property of GO. Excited by the low-power near-infrared light, GO-MNF is capable of initiating the phase transition of surrounding solvent (such as N, N-dimethylformamide, deionized water) to generate photothermal microbubbles. As a result, in the N, N-dimethylformamide, the microbubbles grows in a certain cycle, and stirs the liquid repeated. In the microfluidic chip, the microbubbles can manipulate micro/nano particles and wires. In the deionized water, the microbubble is stable and not easy to break, which can be used to gather particles. The microheater has the superiorities of easy fabrication, small size, low loss, low excitation power, and high efficiency, which would have prospective applications in micro-electromechanical systems, lab-on-a-chip, and other techniques.