Facile use of silver nanoparticles-loaded alumina/silica in nanofluid formulations for enhanced catalytic performance toward 4-nitrophenol reduction

Mannu, R. et al. (2021) Facile use of silver nanoparticles-loaded alumina/silica in nanofluid formulations for enhanced catalytic performance toward 4-nitrophenol reduction. International Journal of Environmental Research and Public Health, 18(6), 2994. (doi: 10.3390/ijerph18062994) (PMID:33803950) (PMCID:PMC7999000)

Abstract

The introduction of toxic chemicals into the environment can result in water pollution leading to the degradation of biodiversity as well as human health. This study presents a new approach of using metal oxides (Al2O3 and SiO2) modified with a plasmonic metal (silver, Ag) nanoparticles (NPs)-based nanofluid (NF) formulation for environmental remediation purposes. Firstly, we prepared the Al2O3 and SiO2 NFs of different concentrations (0.2 to 2.0 weight %) by ultrasonic-assisted dispersion of Al2O3 and SiO2 NPs with water as the base fluid. The thermo-physical (viscosity, activation energy, and thermal conductivity), electrical (AC conductivity and dielectric constant) and physical (ultrasonic velocity, density, refractive index) and stability characteristics were comparatively evaluated. The Al2O3 and SiO2 NPs were then catalytically activated by loading silver NPs to obtain Al2O3/SiO2@Ag composite NPs. The catalytic reduction of 4-nitrophenol (4-NP) with Al2O3/SiO2@Ag based NFs was followed. The catalytic efficiency of Al2O3@Ag NF and SiO2@Ag NF, for the 4-NP catalysis, is compared. Based on the catalytic rate constant evaluation, the catalytic reduction efficiency for 4-NP is found to be superior for 2% weight Al2O3@Ag NF (92.9 × 10−3 s−1) as compared to the SiO2@Ag NF (29.3 × 10−3 s−1). Importantly, the enhanced catalytic efficiency of 2% weight Al2O3@Ag NF for 4-NP removal is much higher than other metal NPs based catalysts reported in the literature, signifying the importance of NF formulation-based catalysis.

• Item Type: Articles
• Additional Information: This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. NRF-2019R1A2C3003890).
• Keywords: Nanofluids, metal oxides, silver nanoparticles, thermo-physical properties, catalytic reduction, 4-nitrophenol.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Vellaisamy, Professor Roy and Karthikeyan, Dr Vaithinathan

Creator Roles

Roy, V. A.L.: Data curation, Validation, Writing – review and editing

• Authors: Mannu, R., Karthikeyan, V., Veerappa, M. M., Roy, V. A.L., Gopalan, A.-I., Saianand, G., Sonar, P., Xu, B., Lee, K.-P., Kim, W.-J., Lee, D.-E., and Kannan, V.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: International Journal of Environmental Research and Public Health
• Publisher: MDPI
• ISSN: 1661-7827
• ISSN (Online): 1660-4601
• Published Online: 15 March 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in International Journal of Environmental Research and Public Health 18(6): 2994
• Publisher Policy: Reproduced under a Creative Commons License