College of Civil Engineering, Fuzhou University, 350116, Fujian, China; Institute of Advanced Energy Materials, Fuzhou University, 350002, Fujian, China; Department of Chemical & Environmental Engineering, University of Arizona, 1133 E James E Rogers Way, Harshbarger 108, Tucson, AZ, 85721-0011, USA.
College of Civil Engineering, Fuzhou University, 350116, Fujian, China.
Chemosphere. 2018 Oct;209:44-52. doi: 10.1016/j.chemosphere.2018.06.036. Epub 2018 Jun 5.
In this work, zeolitic imidazolate framework-8 (ZIF-8) was successfully synthesized by a facile reaction via water and alcohol solvents at room temperature. Additionally, Ag/AgCl@ZIF-8 was successfully fabricated by doping Ag/AgCl onto ZIF-8, which were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), along with UV-visible diffuse reflectance spectra (UV-vis DRS). The Ag/AgCl@ZIF-8 nanoparticles exhibited high photocatalytic activity, durability, and efficiency for the degradation of methylene blue dye (MB). The results illustrate that the band gap of Ag/AgCl@ZIF-8 is lower than that of ZIF-8, which explains the enhancement of MB degradation under UV light irradiation. The conditions affecting the photocatalytic degradation, including the dosage of photocatalyst, the initial concentration of MB, pH value, and hardness of water were systematically evaluated. In addition, the photocatalytic mechanism was explored by three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, the effect of ZnO to photocatalytic activity was excluded, and a possible pathway of MB degradation was proposed by analysis of intermediates via liquid chromatography in combination with hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). The high photocatalytic ability of Ag/AgCl@ZIF-8 shows great application potential for the oxidation of organic pollutants in water.
在这项工作中，沸石咪唑酯骨架-8（ZIF-8）通过水和醇溶剂在室温下的简单反应成功合成。此外，通过将 Ag/AgCl 掺杂到 ZIF-8 中成功制备了 Ag/AgCl@ZIF-8，其通过粉末 X 射线衍射（XRD）、场发射扫描电子显微镜（SEM）、能谱（EDS）以及紫外-可见漫反射光谱（UV-vis DRS）进行了表征。Ag/AgCl@ZIF-8 纳米粒子表现出高的光催化活性、耐久性和效率，可用于降解亚甲基蓝染料（MB）。结果表明，Ag/AgCl@ZIF-8 的带隙低于 ZIF-8，这解释了在紫外光照射下 MB 降解增强的原因。系统评估了影响光催化降解的条件，包括光催化剂的用量、MB 的初始浓度、pH 值和水的硬度。此外，通过三维激发-发射矩阵（3D-EEM）荧光光谱探讨了光催化机理，排除了 ZnO 对光催化活性的影响，并通过液相色谱与混合四极杆飞行时间质谱（LC-QTOF-MS）联用分析中间产物提出了 MB 降解的可能途径。Ag/AgCl@ZIF-8 的高光催化能力表明其在水中氧化有机污染物方面具有很大的应用潜力。
