Solar-driven strongly coupled plasmonic Au nanoarrays on mesoporous silica nanodisks enable selective fungal and bacterial inactivation in well water

Zhuoyun Tang; Dingren Ma; Jingling Yang; Jinjuan Chen; Zhuohang Lin; Qiwen Liang; Yimu Jiao; Wei Qu; Dehua Xia

doi:10.1016/j.watres.2023.120612

Solar-driven strongly coupled plasmonic Au nanoarrays on mesoporous silica nanodisks enable selective fungal and bacterial inactivation in well water

Water Res. 2023 Oct 15:245:120612. doi: 10.1016/j.watres.2023.120612. Epub 2023 Sep 13.

Authors

Zhuoyun Tang¹, Dingren Ma¹, Jingling Yang², Jinjuan Chen¹, Zhuohang Lin¹, Qiwen Liang¹, Yimu Jiao¹, Wei Qu¹, Dehua Xia³

Affiliations

¹ School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
² School of Environment, Jinan University, Guangzhou 510632, China.
³ School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510275, China. Electronic address: xiadehua3@mail.sysu.edu.cn.

PMID: 37729695
DOI: 10.1016/j.watres.2023.120612

Abstract

Well water is an important water source in isolated rural areas but easily suffers from microbial contamination. Herein, we anchored periodic Au nanoarrays on mesoporous silica nanodisks (Au-MSN) to fabricate a solar-driven nano-stove for well water disinfection. The solar/Au-MSN process completely inactivated 3.98, 6.55, 7.11 log₁₀ cfu/mL, and 3.37 log₁₀ pfu/mL of Aspergillus niger spores, Escherichia coli, chlorine-resistant Spingopyxis sp. BM1-1, and bacteriophage MS2 within 5 min, respectively. Moreover, the complete inactivation of various microorganisms (even at a viable but nonculturable state) was achieved in the flow-through reactor under natural solar light in real well water matrixes. Thorough characterizations and theoretical simulations verified that the densely anchoring strategy of Au-MSN's nanoarray worked on broadband absorption via the photon confinement effect, and trace amounts of Au can induce strong electromagnetic fields and collective localized heating. The resulting surge of ¹O₂ and heat synergically destroyed membranes, dysfunction cellular self-defense and metabolic system, induced intracellular oxidative stress, and ultimately inactivated microorganisms. Additionally, the ¹O₂-dominated oxidation and cell adhesion facilitated the selective disinfection in real well water matrixes. This study provides a cost-effective and practical solution for efficient well water disinfection, which assists isolated rural areas in getting safe drinking water.

Keywords: Fungal spores; Photothermal effect; Solar disinfection; Synergistic effect; Well water.