Park Shin Geun, Kim Yong Seok, Lee Hyunjung, Lee Wonmok
Department of Chemistry, Sejong University, 209 Neungdong-ro, Gwngjin-gu, Seoul, 05006, Korea.
Department of Materials Science and Engineering, Kookmin University, 77 Jeongneung-ro, Seongbuk- gu, Seoul, 02707, Korea.
Sci Rep. 2025 Apr 10;15(1):12212. doi: 10.1038/s41598-025-92160-z.
In this study, we investigated a color-tunable carboxyl-rich carbon inverse photonic ball (CIPB) ink, which was fabricated using a polymeric photonic ball (PB) as a template, with characteristic self-assembled opalline structures from monodisperse polystyrene (PS) microspheres. The PBs were prepared on a large scale via an optimized diffusive drying method using an aqueous dispersion of polystyrene microspheres. Via acid-catalyzed thermal dehydration of monosaccharides within the interstitial space of PB followed by template removal, iridescent CIPB, which is insoluble in water or organic solvents because the crosslinked structure is similar to a naturally occurring humin, was obtained. The use of PS microspheres of different sizes for the preparation of the respective PBs resulted in CIPBs with different structural colors. Optical characterization revealed that the individual CIPB particles exhibit specific colors on the basis of the angular dependence of the Bragg condition for each particle. The overall structural color of the CIPB ink was sensitively tuned by changing dispersing media with different indices of refraction. Spectroscopic analysis confirmed the presence of carboxyl groups within CIPB due to the light thermal condensation of sugar, and the osmotic swelling/deswelling of the charged CIPB at pH values above/below the pKa of the bound carboxylate drove the reversible pH-responsive changes in structural color, indicating the promising applicability of CIPB as a colorimetric chemical sensor.
在本研究中，我们研究了一种颜色可调的富含羧基的碳反光子球（CIPB）墨水，它是以聚合物光子球（PB）为模板制备的，具有由单分散聚苯乙烯（PS）微球构成的特征性自组装蛋白石结构。通过使用聚苯乙烯微球的水分散体，经由优化的扩散干燥方法大规模制备PB。通过对PB间隙空间内的单糖进行酸催化热脱水，随后去除模板，得到了彩虹色的CIPB，由于其交联结构类似于天然存在的腐殖质，所以它不溶于水或有机溶剂。使用不同尺寸的PS微球制备各自的PB，得到了具有不同结构颜色的CIPB。光学表征表明，基于每个颗粒的布拉格条件的角度依赖性，单个CIPB颗粒呈现特定颜色。通过改变具有不同折射率的分散介质，灵敏地调节了CIPB墨水的整体结构颜色。光谱分析证实，由于糖的轻度热缩合，CIPB中存在羧基，并且在高于/低于结合羧酸盐的pKa的pH值下，带电CIPB的渗透溶胀/去溶胀驱动了结构颜色的可逆pH响应变化，表明CIPB作为比色化学传感器具有广阔的应用前景。
