CelloMOF: Nanocellulose Enabled 3D Printing of Metal–Organic Frameworks

Abstract

3D printing is recognized as a powerful tool to develop complex geometries for a variety of materials including nanocellulose. Herein, a one-pot synthesis of 3D printable hydrogel ink containing zeolitic imidazolate frameworks (ZIF-8) anchored on anionic 2,2,6,6-tetramethylpiperidine-1-oxylradicalmediated oxidized cellulose nanofibers (TOCNF) is presented. The synthesis approach of ZIF-8@TOCNF (CelloZIF8) hybrid inks is simple, fast (≈30 min), environmentally friendly, takes place at room temperature, and allows easy encapsulation of guest molecules such as curcumin. Shear thinning properties of the hybrid hydrogel inks facilitate the 3D printing of porous scaffolds with excellent shape fidelity. The scaffolds show pH controlled curcumin release. The synthesis route offers a general approach for metal-organic frameworks (MOF) processing and is successfully applied to other types of MOFs such as MIL-100 (Fe) and other guest molecules as methylene blue.This study may open new venues for MOFs processing and its large-scale applications.

Hierarchical Metal–Organic Frameworks with Macroporosity: Synthesis, Achievements, and Challenges

“…2a, b), with the amount of HKUST-1 loaded onto the template increasing with increased reaction time. The as-obtained composites were tested for electrochemical [149] sensing of glucose, showing very promising activity with a relatively wide linear range (15.84 µM-5.62 mM), low limit of detection (4.8 µM), and a high sensitivity (28.67 µA mM −1 cm −2 ). The excellent electrocatalytic activity was attributed to the presence of macropores in the hierarchical structure which was led to improved mass transfer of the glucose.…”

Synthesis through 3D printing: formation of 3D coordination polymers

“…16 Our group reported the 3D-printing of Cu-BTC MOF for the adsorption of organic dyes from solutions, 17 and Lyu et al reported a 3D-printed cobalt-based MOF embedded within an organic binder for energy storage applications. 18 More examples on 3D-printed MOFs were explored by Lawson et al and Sultan et al 19,20 Recently, our group, in collaboration with Amo-Ochoa and Zamora, also published the 3D-printing of a Cu 2+ coordination polymer for the colorimetric sensing of humidity and water. 21 In these prior works, the coordination polymers were synthesized prior to the printing, mostly in the form of particles, which were later dispersed within matrix forming materials, since the CP particles could not form a stand-alone 3D object without binders.…”

3D‐Structured Monoliths of Nanoporous Polymers by Additive Manufacturing

“…A similar binder‐free approach was shown for the MOF HKUST‐1 that was printed as a gel, although, with low resolution only on the millimeter scale . A somewhat different approach is based on the printing of a paste that consists of cellulose pulp fibers with surface‐grown MOF particles . Recently, also a covalent organic framework (COF) was printed from a pre‐polymerized precursor gel with a subsequent posttreatment to achieve the full formation of the accessible framework material in a 3D monolithic structure .…”