Yang Hao, Hu Xiaojing, Su Chunping, Liu Yunling, Chen Rong
School of Chemistry and Environmental Engineering and Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan Institute of Technology, Wuhan, 430073, P. R. China.
Phys Chem Chem Phys. 2017 Dec 6;19(47):31666-31674. doi: 10.1039/c7cp05848a.
In this work, we demonstrated a general approach to realize superhydrophobic-superhydrophilic reversible transition over hydrophilic bismuth-related micro-/nanomaterials. Different superhydrophobic bismuth-based micro-/nanomaterials, including BiOCOOH, BiO, (BiO)CO and BiOCl, were obtained by modification with stearic acid, regardless of their morphologies. The reversible wettability of the bismuth-related materials upon alternative UV-vis irradiation and dark storage were investigated via cyclic experiments. The results indicated that the reversible wetting behavior was highly related with the photocatalytic activities of the bismuth-based materials. High photocatalytic activity resulted in less reversible cycles between superhydrophobicity and superhydrophilicity due to the photodegradation of stearic acid. Moreover, with the increase of cycle number, the required minimal time for photo-induced superhydrophilicity decreased and the minimal time for the recovery of superhydrophobicity under dark storage increased. Based on peak deconvolution analysis of XPS and FTIR spectra, a comprehensive understanding of reversible wettability of the bismuth-related micro-/nanomaterials was proposed. This work provides a new strategy to fabricate superhydrophobic-superhydrophilic switchable surfaces for most hydrophilic inorganic materials with different morphologies and photocatalytic activities.
在这项工作中，我们展示了一种在亲水性铋基微纳米材料上实现超疏水 - 超亲水可逆转变的通用方法。通过硬脂酸改性获得了不同的超疏水铋基微纳米材料，包括BiOCOOH、BiO、(BiO)₂CO₃和BiOCl，无论它们的形态如何。通过循环实验研究了铋基材料在交替紫外 - 可见光照和暗处储存时的可逆润湿性。结果表明，可逆润湿行为与铋基材料的光催化活性高度相关。由于硬脂酸的光降解，高光催化活性导致超疏水和超亲水之间的可逆循环次数减少。此外，随着循环次数的增加，光致超亲水性所需的最短时间减少，暗处储存下超疏水性恢复的最短时间增加。基于XPS和FTIR光谱的峰去卷积分析，对铋基微纳米材料的可逆润湿性提出了全面的理解。这项工作为制造具有不同形态和光催化活性的大多数亲水性无机材料的超疏水 - 超亲水可切换表面提供了一种新策略。
