Chen Lianqing, Zhang Chengjiang, Wu Lamei, Lv Kangle, Deng Kejian, Wu Tsunghsueh
Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China.
Department of Chemistry, University of Wisconsin-Platteville, Platteville, WI, 53818, USA.
Nanoscale Res Lett. 2018 Oct 24;13(1):336. doi: 10.1186/s11671-018-2745-5.
A serials of biomimetic photocatalyst zinc(II) meso-tetra(4-carboxyphenyl)porphyrinato (ZnTCP)-sensitized 3D hierarchical TiO hollow nanoboxes (TiO-HNBs) assembled by six ordered nanosheets with dominant {001} facets exposure (ZnTCP@TiO-HNBs) have been successfully synthesized by a facile one-pot solvothermal method via a topological transformation process with TiOF as template. Infrared spectra (IR), UV-vis spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed that ZnTCP played a decisive role in constructing 3D hollow nanoboxes through the formation of ester bond combined to TiO-HNBs, which also provided a transferring photo excited electrons bridge to sensitize TiO-HNBs for enhancing visible-light response. Due to the superior sensitization and biomimetic activity of ZnTCP, the photodegradation rate of rhodamine B (RhB) of as-prepared ZnTCP@TiO-HNBs with ZnTCP/TiOF mass ratio of 2% (T-2p) improves 3.6 times compared to that of TiO-HNBs with a degradation yield of 99% for 2 h under simulated sunlight irradiation (> 420 nm). The enhanced photodegradation ability was attributed to synergistic visible photocatalytic mechanism of biomimetic catalyst, which can not only produce hydroxyl radical (•OH) and superoxide radical (•O) coming from the excitation process of ZnTCP sensitized TiO-HNBs, but also generate singlet oxygen (O) that was only provided by biomimetic enzyme porphyrins. Furthermore, the photocatalyst showed good recycling stability and dispersibility after five rounds, ascribed to ZnTCP strong chemical bonding to the support TiO-HNBs. By means of electrochemical cyclic voltammetry analysis, the effect of central zinc ions and parent porphyrin rings on the redox property of biomimetic catalyst was studied.
通过一种简便的一锅溶剂热法，以TiOF为模板，经拓扑转变过程成功合成了一系列由六个有序纳米片组装而成、具有显著{001}面暴露的仿生光催化剂锌（II）中-四（4-羧基苯基）卟啉（ZnTCP）敏化的3D分级TiO中空纳米盒（TiO-HNBs）（ZnTCP@TiO-HNBs）。红外光谱（IR）、紫外-可见光谱和X射线光电子能谱（XPS）证实，ZnTCP通过与TiO-HNBs形成酯键在构建3D中空纳米盒中起决定性作用，这也提供了一个转移光激发电子的桥梁来敏化TiO-HNBs以增强可见光响应。由于ZnTCP具有优异的敏化和仿生活性，所制备的ZnTCP/TiOF质量比为2%的ZnTCP@TiO-HNBs（T-2p）对罗丹明B（RhB）的光降解速率比TiO-HNBs提高了3.6倍，在模拟太阳光照射（>420nm）下2小时的降解产率为99%。增强的光降解能力归因于仿生催化剂的协同可见光催化机制，其不仅能产生来自ZnTCP敏化TiO-HNBs激发过程的羟基自由基（•OH）和超氧自由基（•O），还能产生仅由仿生酶卟啉提供的单线态氧（O）。此外，该光催化剂在经过五轮循环后表现出良好的循环稳定性和分散性，这归因于ZnTCP与载体TiO-HNBs的强化学键合。通过电化学循环伏安分析，研究了中心锌离子和母体卟啉环对仿生催化剂氧化还原性能的影响。
