High-intensive aerogels constructed through in-situ growth of ZIF-8-NH2 on wood for efficient formaldehyde absorption

Abstract

Metal-organic frameworks (MOFs) are highly advantageous due to their tunable pore size, exceptional thermal and chemical stability, and high specific surface area, making them ideal for applications in formaldehyde adsorption. However, the practical use of powdered MOFs is significantly hindered by their recycling challenges. In this research, wood-based composite aerogels (WAZN-X) were successfully prepared through loading Zeolitic Imidazolate Framework-8-NH₂ (ZIF-8-NH₂) inside wood aerogels. Ascribing to the elimination of lignin and hemicellulose, the enlarged pore structures of wood aerogels and the potential interactions (e.g., hydrogen bonding and electrostatic attractions) between components promoted the uniformly depositing of ZIF-8-NH₂ nanocrystals. The WAZN-X aerogels displayed excellent mechanical strength (e.g., the longitudinal Young’s modulus of 68.57 MPa) and promising formaldehyde adsorption performance (e.g., a stable formaldehyde removal rate of 98.11 %), and kept commendable reusability (95.98 % after 5 cycles). This research provides a new insight for developing high-value functional composite adsorbents for efficient formaldehyde purification.