Bacterial Nanocellulose/MoS2 Hybrid Aerogels as Bifunctional Adsorbent/Photocatalyst Membranes for in-Flow Water Decontamination

Author(s)

Ferreira-Neto, Elias P. ^[1] ; Ullah, Sajjad ^{[1, 2, 3]} ; da Silva, Thais C. A. ^[1] ; Domeneguetti, Rafael R. ^[1] ; Perissinotto, Amanda P. ^[4] ; de Vicente, Fabio S. ^[5] ; Rodrigues-Filho, Ubirajara P. ^[4] ; Ribeiro, Sidney J. L. ^[1]

Affiliation

^[1] Sao Paulo State Univ, Inst Chem, BR-14800060 Araraquara, SP - Brazil

^[2] Univ Fed Mato Grosso do Sul, Inst Phys, BR-79070900 Campo Grande, MS - Brazil

^[3] Univ Peshawar, Inst Chem Sci, Peshawar - Pakistan

^[4] Univ Sao Paulo, Inst Chem Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[5] Sao Paulo State Univ, Inst Geosci & Exact Sci, Dept Phys, BR-13500970 Rio Claro, SP - Brazil

• Document type: Journal article
• Source: ACS APPLIED MATERIALS & INTERFACES; v. 12, n. 37, p. 41627-41643, SEP 16 2020.
• Web of Science Citations: 5

Abstract

To address the problems associated with the use of unsupported nanomaterials, in general, and molybdenum disulfide (MoS2), in particular, we report the preparation of self-supported hybrid aerogel membranes that combine the mechanical stability and excellent textural properties of bacterial nanocellulose (BC)-based organic macro/mesoporous scaffolds with the excellent adsorption-cum-photocatalytic properties and high contaminant removal performance of MoS2 nanostructures. A controlled hydrothermal growth and precise tuning of the synthetic parameters allowed us to obtain BC/MoS2-based porous, self-supported, and stable hybrid aerogels with a unique morphology resulting from a molecular precision in the coating of quantum-confined photocatalytic MoS2 nanostructures (2-4 nm crystallite size) on BC nanofibrils. These BC/MoS2 samples exhibit high surface area (97-137 m(2).g(-1)) and pore volume (0.28-0.36 cm(3).g(-1)) and controlled interlayer distances (0.62-1.05 nm) in the MoS2 nanostructures. Modification of BC with nanostructured MoS2 led to an enhanced pollutants removal efficiency of the hybrid aerogels both by adsorptive and photocatalytic mechanisms, as indicated by a detailed study using a specifically designed membrane photoreactor containing the developed photoactive/adsorptive BC/MoS2 hybrid membranes. Most importantly, the prepared BC/Mo(S)2 aerogel membranes showed high performance in the photoassisted in-flow removal of both organic dye (methylene blue (MB)) molecules (96% removal within 120 min, K-obs = 0.0267 min(-1)) and heavy metal ions (88% Cr(VI) removal within 120 min, K-obs = 0.0012 min(-1)), separately and/or simultaneously, under UV-visible light illumination as well as excellent recyclability and photostability. Samples with interlayer expanded MoS2 nanostructures were particularly more efficient in the removal of smaller species (CrO42-) as compared to larger (MB) dye molecules. The prepared hybrid aerogel membranes show promising behavior for application in in-flow water purification, representing a significant advancement in the use of self-supported aerogel membranes for photocatalytic applications in liquid media. (AU)

• FAPESP's process: 15/22828-6 - Pushing the boundaries of optical fibers: from photonics to optogenetics and environmental monitoring
• Grantee: Younes Messaddeq
• Support Opportunities: Research Projects - SPEC Program
• FAPESP's process: 18/01934-0 - Aerogels based on transition metal disulfides and bacterial cellulose: bifunctional nanomaterials with photocatalytic and adsorptive properties for environmental applications
• Grantee: Elias Paiva Ferreira Neto
• Support Opportunities: Scholarships in Brazil - Post-Doctoral