ICFO-Institut de Ciencies Fotoniques , The Barcelona Institute of Science and Technology , Castelldefels, 08860 Barcelona , Spain.
ICREA-Institució Catalana de Recerca i Estudis Avançats , 08810 Barcelona , Spain.
Nano Lett. 2018 Nov 14;18(11):6660-6664. doi: 10.1021/acs.nanolett.8b01164. Epub 2018 Jul 13.
The use of photothermal sensitizers to facilitate the sintering of polymer powders is rapidly becoming a pivotal additive manufacturing technology, impacting multiple sectors of industry. However, conventional carbon-based sensitizers can only produce black or gray objects. To create white or colorful prints with this method, visibly transparent equivalents are needed. Here, we address this problem by designing resonant photothermal sensitizers made of plasmonic nanoparticles that strongly absorb in the near-infrared, while only minimally interacting with visible light. Gold nanorods were coated with silica before being mixed with polyamide powders to create stable colorful nanocomposite powders. At resonance, these composites showed greatly improved light-to-heat conversion compared with equivalent composites using the industry standard carbon black as a sensitizer and could be sintered using low-power light sources. Furthermore, they appear much whiter and can produce brightly colored 3D objects when mixed with dyes. Our results open a new route to utilize plasmonic nanoparticles to produce colorful and functional 3D-printed objects.
光热敏化剂的使用促进了聚合物粉末的烧结，这一技术正在迅速成为一种关键的增材制造技术，影响着多个行业。然而，传统的碳基敏化剂只能产生黑色或灰色的物体。为了用这种方法制造白色或彩色的打印件，需要使用可见透明的等效物。在这里，我们通过设计由等离子体纳米粒子组成的共振光热敏化剂来解决这个问题，这些纳米粒子在近红外光区域强烈吸收，而与可见光的相互作用最小。金纳米棒先被涂覆二氧化硅，然后与聚酰胺粉末混合，以制造稳定的彩色纳米复合材料粉末。在共振时，与使用行业标准的炭黑作为敏化剂的等效复合材料相比，这些复合材料显示出了大大提高的光热转换效率，并且可以用低功率光源进行烧结。此外，它们看起来更白，并且当与染料混合时可以产生鲜艳的彩色 3D 物体。我们的研究结果为利用等离子体纳米粒子生产彩色和功能性 3D 打印物体开辟了一条新途径。
