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Reversibly switching water droplets wettability on hierarchical structured Cu₂S mesh for efficient oil/water separation.

ABSTRACT: Surfaces with reversible wettability have broad applications but remain challenging since the switching process is usually energy intensive and complex. In this paper, a pyramid shaped Cu₂S film with hierarchical micro/nanostructures is formed on a commercial copper mesh. This film is formed by a spontaneous redox sulfuration reaction and results in a roughened surface, which enables reversible wetting transition between superhydrophilicity to superhydrophobicity. This switching occurs by simple processes such as alternately storing in air or using an ethanol solution treatment and yields cyclic wettability switching for many cycles. This convenient wetting transition behavior, as well as strong stability and efficient oil/water separation with efficiency exceeding 98%, renders it as a potentially useful mesh material for switchable surfaces.

SUBMITTER: Xu S

PROVIDER: S-EPMC6713748 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Reversibly switching water droplets wettability on hierarchical structured Cu2S mesh for efficient oil/water separation.

Xu Shanya S Sheng Rui R Cao Yali Y Yan Junfeng J

Scientific reports 20190828 1

Surfaces with reversible wettability have broad applications but remain challenging since the switching process is usually energy intensive and complex. In this paper, a pyramid shaped Cu2S film with hierarchical micro/nanostructures is formed on a commercial copper mesh. This film is formed by a spontaneous redox sulfuration reaction and results in a roughened surface, which enables reversible wetting transition between superhydrophilicity to superhydrophobicity. This switching occur ...[more]

PMID: 31462670

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