Aerogels from copper (II)-cellulose nanofibers and carbon nanotubes as absorbents for the elimination of toxic gases from air

Vipin Adavan Kiliyankil; Bunshi Fugetsu; Ichiro Sakata; Zhipeng Wang; Morinobu Endo

doi:10.1016/j.jcis.2020.08.100

Aerogels from copper (II)-cellulose nanofibers and carbon nanotubes as absorbents for the elimination of toxic gases from air

J Colloid Interface Sci. 2021 Jan 15;582(Pt B):950-960. doi: 10.1016/j.jcis.2020.08.100. Epub 2020 Aug 29.

Authors

Vipin Adavan Kiliyankil¹, Bunshi Fugetsu², Ichiro Sakata³, Zhipeng Wang⁴, Morinobu Endo⁵

Affiliations

¹ Faculty of Engineering, The University of Tokyo, Bunkyo-ku, Yayoi 2-11-16, Tokyo 113-8656, Japan. Electronic address: vipin@ipr-ctr.t.u-tokyo.ac.jp.
² Institute for Future Initiatives, The University of Tokyo, Bunkyo-ku, Yayoi 2-11-16, Tokyo 113-8656, Japan.
³ Faculty of Engineering, The University of Tokyo, Bunkyo-ku, Yayoi 2-11-16, Tokyo 113-8656, Japan; Institute for Future Initiatives, The University of Tokyo, Bunkyo-ku, Yayoi 2-11-16, Tokyo 113-8656, Japan.
⁴ Institute of Advanced Materials, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang, Jiangxi Province 330022, China.
⁵ Institute of Carbon Science and Technology, Shinshu University, 4-17-1, Wakasato, Nagano 380-8553, Japan.

PMID: 32927175
DOI: 10.1016/j.jcis.2020.08.100

Abstract

A novel deodorizer that is capable of selectively eliminating the odorous chemicals, such as ammonia, trimethylamine, hydrogen sulfide and methyl mercaptan, is described. The deodorizer is a nanostructured aerogel by nature, consisting of 2,2-6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized cellulose nanofibrils (CNF), transition metal divalent cations (M²⁺), and multi-walled carbon nanotubes (CNT) as the constitutive elements. CNF are firstly mixed with M²⁺ (M²⁺, in this paper, typifies Ni²⁺, Co²⁺ and Cu²⁺) to form CNF-M²⁺ complexes, monodispersed CNT is then mixed to prepare CNT/CNF-M²⁺ waterborne slurries; CNT/CNF-M²⁺ hybridized aerogels are finally obtained via freezing-drying of the CNT/CNF-M²⁺ waterborne slurries. The CNT/CNF-M²⁺ aerogels are a foam-like structure consisting of CNF and CNT as backbones and M²⁺ as linkers. The aerogels show higher capabilities (in comparison with activated carbon) for selectively adsorbing ammonia, trimethylamine, hydrogen sulfide and methyl mercaptan. Computing simulations suggest a theoretical conclusion that the odorous chemicals are absorbed in a preferring manner of bimolecular absorptions via the M²⁺ moieties. The CNT/CNF-M²⁺ hybridized aerogels are lightweight, eco-friendly, and easy to produce in industrial scales. Our new finding, as is described in this paper, demonstrates potential applications of the TEMPO-oxidized CNF to the field of deodorizations.

Keywords: Absorption; Aerogel deodorizer; Air pollution; Ammonia; Carbon nanotubes; Cellulose nanofiber; Hydrogen sulfide; Methyl mercaptan; Transition metal divalent ions; Trimethylamine.