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Nano Research 2023, 16(4): 4219-4224 https://doi.org/10.1007/s12274-021-4041-4
Research Article | Issue | Published: 17 January 2022

Antibacterial evaporator based on reduced graphene oxide/polypyrrole aerogel for solar-driven desalination

Show Author's Information Mengru Zhang1,§,  Fan Xu1,§,  Wenjie Liu1,  Yaqi Hou1,  Liyun Su2,  Xin Zhang1,  Ruihua Zhang1,  Lijun Zhou1,  Xiaomei Yan2,  Miao Wang3( ),  Xu Hou1,4,5( ),  Yang Cao1,6( )
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
Department of Chemical Biology, MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
College of Materials, Xiamen University, Xiamen 361005, China
College of Physical Science and Technology, Xiamen University, Xiamen 361005, China
Tan Kah Kee Innovation Laboratory, Xiamen 361005, China
Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen 361005, China

§ Mengru Zhang and Fan Xu contributed equally to this work.

Keywords:
polypyrrole, antibacterial property, solar-driven steam generation, interfacial heating, graphene-based material
Topics:
Graphene oxide
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Zhang M, Xu F, Liu W, et al. Antibacterial evaporator based on reduced graphene oxide/polypyrrole aerogel for solar-driven desalination. Nano Research, 2023, 16(4): 4219-4224. https://doi.org/10.1007/s12274-021-4041-4
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Abstract Full text Electronic supplementary material About this article

Solar-driven water evaporation is a sustainable method to purify seawater. Nevertheless, traditional volumetric water-evaporation systems suffer from the poor sunlight absorption and inefficient light-to-thermal conversion. Also, their anti-bacterial and anti-fouling performances are crucial for the practical application. Herein, we introduce reduced graphene oxide (RGO) with broadband absorbance across the entire solar spectrum, and polypyrrole (PPy), an antibacterial polymer with efficient solar absorption and low thermal conductivity, to develop integrated RGO/PPy aerogel as both the solar absorber and evaporator for highly efficient solar-driven steam generation. As a result, the RGO/PPy aerogel shows strong absorption and good photothermal performance, leading to an evaporation rate of 1.44 kg·m−2·h−1 and high salt rejection (up to 99.99%) for real seawater, with photothermal conversion efficiency > 90% under one sun irradiation. The result is attributed to the localized heat at the air–water interface by the RGO/PPy and its porous nature with functional groups that facilitates the water evaporation. Moreover, the RGO/PPy demonstrates excellent durability and antibacterial efficiency close to 100% for 12 h, crucial characteristics for long-term application. Our well-designed RGO/PPy aerogel with efficient water desalination performance and antibacterial property provides a straightforward approach to improve the solar-driven evaporation performance by multifunctional materials integration, and offers a viable route towards practical seawater desalination.


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Electronic supplementary material
About this article

Antibacterial evaporator based on reduced graphene oxide/polypyrrole aerogel for solar-driven desalination

Show Author's information Mengru Zhang1,§, Fan Xu1,§, Wenjie Liu1, Yaqi Hou1, Liyun Su2, Xin Zhang1, Ruihua Zhang1, Lijun Zhou1, Xiaomei Yan2, Miao Wang3( ), Xu Hou1,4,5( ), Yang Cao1,6( )
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
Department of Chemical Biology, MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
College of Materials, Xiamen University, Xiamen 361005, China
College of Physical Science and Technology, Xiamen University, Xiamen 361005, China
Tan Kah Kee Innovation Laboratory, Xiamen 361005, China
Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen 361005, China

§ Mengru Zhang and Fan Xu contributed equally to this work.

Abstract

Solar-driven water evaporation is a sustainable method to purify seawater. Nevertheless, traditional volumetric water-evaporation systems suffer from the poor sunlight absorption and inefficient light-to-thermal conversion. Also, their anti-bacterial and anti-fouling performances are crucial for the practical application. Herein, we introduce reduced graphene oxide (RGO) with broadband absorbance across the entire solar spectrum, and polypyrrole (PPy), an antibacterial polymer with efficient solar absorption and low thermal conductivity, to develop integrated RGO/PPy aerogel as both the solar absorber and evaporator for highly efficient solar-driven steam generation. As a result, the RGO/PPy aerogel shows strong absorption and good photothermal performance, leading to an evaporation rate of 1.44 kg·m−2·h−1 and high salt rejection (up to 99.99%) for real seawater, with photothermal conversion efficiency > 90% under one sun irradiation. The result is attributed to the localized heat at the air–water interface by the RGO/PPy and its porous nature with functional groups that facilitates the water evaporation. Moreover, the RGO/PPy demonstrates excellent durability and antibacterial efficiency close to 100% for 12 h, crucial characteristics for long-term application. Our well-designed RGO/PPy aerogel with efficient water desalination performance and antibacterial property provides a straightforward approach to improve the solar-driven evaporation performance by multifunctional materials integration, and offers a viable route towards practical seawater desalination.

Keywords: polypyrrole, antibacterial property, solar-driven steam generation, interfacial heating, graphene-based material

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Publication history
Copyright
Acknowledgements

Publication history

Received: 07 September 2021
Revised: 30 November 2021
Accepted: 05 December 2021
Published: 17 January 2022
Issue date: April 2023

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021

Acknowledgements

Acknowledgements

This study was supported by the National Key R&D Program of China (Nos. 2018YFA0209500 and 2018YFA0306900) and the National Natural Science Foundation of China (Nos. 21872114 and 21627811).

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