No abstract

Development of versatile, broad-spectrum adsorbents for the removal of diverse dyes from contaminated water and oil is highly desirable. In this study, a calcium alginate carbon aerogel (CCA) as an adsorbent for various types of dyes was fabricated from sodium alginate by wet spinning, cross-linking, drying, and high-temperature carbonization. The CCA carbonized at 1000 °C (CCA-1000) showed a good adsorption effect on methylene blue as a cationic dye, methyl orange as an anionic dye, oil red O as a solvent dye, and nine other dyes. Adsorption kinetics, adsorption effect of various parameters such as temperature and solution pH, regeneration performance, and adsorption mechanism were studied. The ultrahigh adsorption capacities of CCA-1000 for malachite green, crystal violet, and acid fuchsin, each with similar triphenylmethane structures, were determined to be 7059, 2390, and 6964 mg g–1, respectively. Interestingly, unlike previously reported carbon aerogels with simple oil–water separation, due to the amphiphilicity, CCA-1000 fabricated herein can be utilized to separate oil–water, surfactant-stabilized water-in-oil, and oil-in-water emulsions with simultaneous dye removal from water and oil. The present work may open up a new avenue for designing carbon aerogels with exceptional performance for broad-spectrum dye adsorption and oil–water separation from sustainable natural seaweed resources.

Colorful blue phase liquid crystal (BPLC) patterns have attracted wide research attention owing to their intriguing and advantageous properties and promising applications. However, it remains a challenge to develop novel and highresolution patterns from BPLC owing to the complicated synthetic procedure for the functional molecules. This study reports a high-resolution "live" pattern by well-designed diffusion of 5CB ink on the wettability-modified BPLC networks. Interestingly, the shape and color of the as-prepared pattern change with time, which results in unique spectra change of the printed pattern, "first red-shift and subsequent blue-shift of the stopband position" and "continuous growth in reflectivity intensity" with time. The hydrophobic substrate greatly suppresses the random spreading and diffusion of ink, contributing to highresolution patterns. The promising applications of live patterns for program display and active labels are demonstrated. Various high-resolution erasable colorful patterns are obtained. The structure reconfiguration of the writing and erasing processes is proved by transmitted electronic microscope images and Kossel diffraction diagrams, which ensures the reversible writing/erasing of the pattern on the membrane. This work is of significance for the development of novel rewritable paper and high-quality optic devices based on BPLC materials.