Raman imaging-assisted customizable assembly of MOFs on cellulose aerogel

Because of a weak interface-bonding force between metal–organic frameworks (MOFs) and substrates and the loss of customization in structural designs owing to the lack of the regulation of ion sites, MOFs tend to escape from the constructed composite template. In this study, the as-prepared 2,2,6,6-tetramethylpiperidyl-1-oxyl (TEMPO)-oxidized algae cellulose nanofibers (TACFs) were used to chelate metal ions at controllable sites and subsequently firmly entangle the assembled MOF crystals. The distribution of ions and synthesized MOFs inside the gel was monitored using Raman imaging technology, which provided an intuitive approach for visually observing the ions and MOF distribution. Using this technology, the synthesized customizable TACFs@ZIF-67 aerogels exhibited a high specific surface area (734.7 m²/g), low density (6.18 mg/cm³), controlled particle distribution, good underwater structural stability, and excellent adsorption of dyes. This study provides a way for solving the dispersion problem of MOFs in nanofibrous aerogels using Raman imaging technology–assisted microcosmic fixed-point design.