Yu Jie, Chen Mengmeng, Hu Neng, Wang Weijia, Lei Lin, Fan Huiqing, Müller-Buschbaum Peter, Zhong Qi
Key Laboratory of Intelligent Textile and Flexible Interconnection of Zhejiang Province & Key Laboratory of Advanced Textile Materials & Manufacturing Technology, Ministry of Education Zhejiang Sci-Tech University 928 Second Avenue Hangzhou 310018 China.
State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China.
Small Sci. 2024 May 8;4(7):2400046. doi: 10.1002/smsc.202400046. eCollection 2024 Jul.
Long-lasting hydrogen evolution and efficient dew harvest is realized via electrospinning a polyvinylidene fluoride (PVDF) membrane on hybrid hydrogels embedded with photocatalytic g-CN/Pt nanosheets. Due to the hindrance of water evaporation by the hydrophobic PVDF membrane, the drying process of the hybrid hydrogels significantly slows down. Hence, the g-CN/Pt nanosheets can continue working on photocatalytic splitting of the water molecules in the hydrogels. When the thickness of the PVDF membrane is 48 μm, the hydrogen evolution rate can reach 2,543 μmol h g, which is 38% more than that of the hybrid hydrogel without covering. Therefore, the hybrid hydrogels covered with PVDF membrane are able to work with high efficiency for 12 h, sufficient for hydrogen evolution during the daytime. In addition, the hydrophobic PVDF membrane and hydrophilic hydrogels construct a Janus structure and induce a fast transport of water molecules from the hydrophobic to hydrophilic side. It is beneficial for the rapid collection of dew in the morning. Based on the long-lasting hydrogen evolution and efficient dew harvest, the present hybrid hydrogels covered with PVDF membrane are very suitable for the environment rich in solar resource and lack of water supply, such as desert or prairie.
通过在嵌入光催化g-CN/Pt纳米片的混合水凝胶上静电纺丝制备聚偏氟乙烯（PVDF）膜，实现了持久的析氢和高效的露水收集。由于疏水性PVDF膜阻碍了水分蒸发，混合水凝胶的干燥过程显著减慢。因此，g-CN/Pt纳米片可以继续对水凝胶中的水分子进行光催化分解。当PVDF膜的厚度为48μm时，析氢速率可达2543μmol h g，比未覆盖的混合水凝胶高出38%。因此，覆盖有PVDF膜的混合水凝胶能够高效工作12小时，足以在白天进行析氢。此外，疏水性PVDF膜和亲水性水凝胶构建了一种Janus结构，并促使水分子从疏水侧向亲水侧快速传输。这有利于早晨露水的快速收集。基于持久的析氢和高效的露水收集，目前覆盖有PVDF膜的混合水凝胶非常适合太阳能资源丰富但缺水的环境，如沙漠或草原。
