One-Pot Exfoliation and Functionalization of Zeolite Nanosheets for Protection of Paper-Based Relics

Two-dimensional (2D) zeolite nanosheets have emerged in many applications due to their structure/surface properties through functional designing. However, the effective and low-cost preparation of functional mono/oligo-layer 2D zeolite and its application in interdiscipline fields still remain a challenge. Here, we report a facile and efficient method of liquid exfoliation by using ethanolamine (ETA) for one-pot liquid exfoliation and surface functionalization. Strikingly, the resultant 2D oligolayer MWW zeolite (denoted as ETA-OL-MWW) has discretely dispersed nanosheets with a well-maintained framework, interface-grafted ETA molecules, and accessible functional sites. The interaction between MWW nanosheets and ETA molecules is characterized and verified as a key factor to achieve, simultaneously, surface functionalization of nanosheets and high dispersion in water-organic solvents. Meanwhile, the stable colloidal ETA-OL-MWW is favorable for functional membrane fabrication via solution-based processing like spin-coating. Based on these features, we pioneer the interdisciplinary use of colloidal ETA-OL-MWW as a multifunctional protective agent for paper-based relics, which is much desirable in the field of cultural heritage preservation. The sufficient, mild, and accessible base sites of ETA-OL-MWW benefit safe deacidification and antiaging but do not damage the original nature of paper relics and color of alkali-sensitive pigments. Moreover, the paper mechanical strength is improved owing to the 2D structure and film-forming property of ETA-OL-MWW, while its antibacteria/fungus and antioxidation for paper relics are revealed and assisted by ETA-functionalized surface. This work is conducive to broadening methods and ideas for exfoliating and functionalizing MWW zeolite and has the significance of designing zeolite-based composite material with interdisciplinary applications.

Automated summary

The study demonstrates a facile and efficient method for liquid exfoliation and surface functionalization of 2D zeolite nanosheets using ethanolamine. The resulting oligolayer MWW zeolite shows well-dispersed nanosheets with maintained framework and grafted molecules, beneficial for applications in fields such as cultural heritage preservation. The interaction between nanosheets and ethanolamine is crucial for achieving both surface functionalization and high dispersion, presenting a promising approach for designing zeolite-based composite materials with interdisciplinary applications.