Facile synthesis, growth mechanism and reversible superhydrophobic and superhydrophilic properties of non-flaking CuO nanowires grown from porous copper substrates

Abstract

Reversible superhydrophobic and superhydrophilic surfaces based on porous substrates covered with CuO nanowires are developed in this study. A facile thermal oxidation method is used to synthesize non-flaking bicrystalline CuO nanowires on porous copper substrates in static air. The effects of thermal oxidation temperature and duration are systemically studied. The growth mechanism of the obtained non-flaking CuO nanowires is presented and the compression stress is believed to be the key driving force. The wettability of the CuO nanowires after chemical modification with trichloro(1H,1H,2H,2H-perfluorooctyl)silane is systemically investigated. The porous substrates covered with CuO nanowires exhibit excellent superhydrophobic performance with almost no water adhesion and no apparent drag resistance, and a maximum static water contact angle of 162 ± 2° is observed. Moreover, a rapid reversibly switchable wettability between superhydrophobic and superhydrophilic states is realized by the alternation of air-plasma treatment and surface fluorination. The porous substrates covered with CuO nanowires will find promising applications in surface and corrosion protection, liquid transportation, oil-water separation, and self-cleaning surfaces.

In-vitro evaluation of copper nanoparticles cytotoxicity on prostate cancer cell lines and their antioxidant, sensing and catalytic activity: One-pot green approach

“…Therefore, the XRD pattern exposed that synthesized BGE/CuNPs are crystalline in nature [46,47]. The formation of CuO was expected as the capping molecules exile the surface and oxidation would occurs which was evident by the gradual decline in the intensity of the SPR bond of BGE/CuNPs.…”

In Situ Synthesis of CuO and Cu Nanostructures with Promising Electrochemical and Wettability Properties

“…Therefore, a compressive stress gradient is generated from the Cu/Cu 2 O interface to CuO/air interface. In order to relieve the compressive stress, Cu atoms tend to migrate from more compressive areas (Cu/Cu 2 O interface) via any weak spots to less compressive ones (CuO surface) in the form of stress‐induced grain boundary diffusion, which has been confirmed by many researchers . The active Cu atoms are rapidly oxidized into CuO in air (they could also be oxidized into Cu 2 O/CuO during the migration from inside the copper foam to the surface) and some may form nanoscale clusters.…”

Preparation of porous Mn-doped CuO microplates and enhanced adsorption performance

“…8 To date, porous copper (II) oxide micro-/nanospheres, nanowires, nanosheets, nanobelts, nanospindles, microrods, hollow octahedra and hexapod nanostructures have been prepared and displayed outstanding properties. [9][10][11][12][13][14][15][16] In the authors' previous work, porous copper (II) oxide microspheres were prepared by the solvothermal method, which showed a good response sensitivity and low detection concentration for ethanol. 8 Porous copper (II) oxide hollow octahedra were synthesized by using metal organic frameworks (MOFs) as templates.…”

“…And then the functionality of the materials can be optimized. 2,[7][8][9][10] Hence, it remains a great challenge to prepare porous copper (II) oxide with adjustable pore structure by way of a facile approach.…”