A lightweight, mechanically strong, and shapeable copper-benzenedicarboxylate/cellulose aerogel for dye degradation and antibacterial applications

Metal-organic frameworks (MOFs) suffer from low processability and recyclability due to their fragile powder form. Supporting MOFs on the lightweight and porous cellulose aerogels is an efficient way to dramatically extend their practical applications. Herein, a metal–organic framework (MOF) composite material, named as copper-benzenedicarboxylate/cellulose aerogel (CuBDC/CA), was designed and synthesized by one-pot precursor preparation of cellulose aerogels anchored with copper, followed by in-situ growth of CuBDC in the presence of terephthalic acid. The characterizations (scanning electron microscopy with energy-dispersive X-ray, powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, stability and mechanical tests) confirmed the successful synthesis of the lightweight (0.0625 ± 0.0010 g/cm3 for 20% CuBDC/CA), mechanically strong, stable, and porous aerogel composites with well-dispersed CuBDC nanosheets. The aerogel composite showed great potential in wastewater treatment, including dye degradation and antibacterial assays. More than 90% methylene blue could be decomposed by CuBDC/CA in 240 min via the Fenton-like reaction, and the recycling test revealed its good reusability. Moreover, this composite exhibited great antibacterial performance (more than 99.99%) towards commonly used lab strains as well as multidrug-resistant pathogens, including Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The screening tests indicated that the mechanism of killing effect was associated with the damage of bacterial envelope integrity. This work has proven that the lightweight and robust MOF/cellulose aerogel is a promising candidate for environmental remediation in practice.