Institute of Materials, Ningbo University of Technology, Ningbo, 315016, P. R. China.
School of Material Science and Engineering, China University of Mining and Technology, Xuzhou, 221116, P. R. China.
Small. 2016 Aug;12(29):4007-17. doi: 10.1002/smll.201600991. Epub 2016 Jun 23.
1D mesoporous materials have attracted extensive interest recently, owning to their fascinating properties and versatile applications. However, it remains as a grand challenge to develop a simple and efficient technique to produce oxide nanofibers with mesoporous architectures, controlled morphologies, large surface areas, and optimal performances. In this work, a facile foaming-assisted electrospinning strategy with foaming agent of tea saponin is used to produce thoroughly mesoporous ZnO nanofibers with high purity and controlled morphology. Interestingly, mesoporous fibers with elliptical cross-section exhibit the significantly enhanced photocatalytic activity for hydrogen production, as compared to the counterparts with circular and rectangular cross-sections, and they also perform better than the commercial ZnO nanopowders. The unexpected shape dependence of photocatalytic activities is attributed to the different stacking modes of the mesoporous fibers, and a geometrical model is developed to account for the shape dependence. This work represents an important step toward producing thoroughly mesoporous ZnO nanofibers with tailored morphologies, and the discovery that fibers with elliptical cross-section render the best performance provides a valuable guideline for improving the photocatalytic performance of such mesoporous nanomaterials.
1D 介孔材料由于其迷人的性质和多样的应用而引起了广泛的关注。然而，开发一种简单高效的技术来制备具有介孔结构、可控形态、大表面积和最佳性能的氧化物纳米纤维仍然是一个巨大的挑战。在这项工作中，采用了一种简单的泡沫辅助静电纺丝策略，使用茶皂素作为发泡剂来制备高纯度和可控形态的完全介孔 ZnO 纳米纤维。有趣的是，与具有圆形和矩形横截面的纤维相比，具有椭圆形横截面的介孔纤维表现出显著增强的光催化制氢活性，并且它们的性能也优于商业 ZnO 纳米粉末。光催化活性的意外形状依赖性归因于介孔纤维的不同堆积模式，并且开发了一个几何模型来解释这种形状依赖性。这项工作代表了朝着制备具有定制形态的完全介孔 ZnO 纳米纤维迈出的重要一步，并且发现具有椭圆形横截面的纤维具有最佳性能，这为改善这种介孔纳米材料的光催化性能提供了有价值的指导。
