Pal Nabin Kumar, Kryschi Carola
Department of Chemistry and Pharmacy and ICMM, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany.
Department of Chemistry and Pharmacy and ICMM, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany.
Chemosphere. 2016 Feb;144:1655-64. doi: 10.1016/j.chemosphere.2015.10.060. Epub 2015 Oct 28.
In this paper, undoped and several differently doped (with Fe(3+), N(-), and γ-Al2O3) TiO2-nanoparticle-based photocatalysts and those covered with ultrasmall gold nanoparticles (AuNPs) were engineered. Their photocatalytic performance was studied by utilizing them for the liquid-phase decomposition of the model dye methylene blue (MB) under visible-light irradiation. The structural, morphological, physico-chemical, and optical properties of the photocatalysts were investigated using X-ray diffraction, X-ray photoelectron spectroscopy, diffuse-reflectance UV-Vis absorption spectroscopy, Raman spectroscopy and transmission electron microscopy. Photodegradation kinetics of MB was followed by measuring the absorbance of MB at 664 nm at different irradiation times, whereas the mineralization of MB was examined by determining the total organic carbon (TOC) content. The photocatalytic activity of TiO2 nanoparticles was shown to be significantly increased by introducing dopants into the crystal lattice and depositing AuNPs on the surface. Among those, γ-Al2O3 doped TiO2 nanoparticles covered with deposited AuNPs show the best photocatalytic performance. Altogether, the here engineered photocatalysts as consisting of doped TiO2 nanoparticles decorated with AuNPs establish novel three-component nanocomposite systems, where synergetic interactions between surface AuNPs, dopants and TiO2 were shown to significantly enhance the photocatalytic activity.
在本文中，制备了未掺杂以及几种不同掺杂（Fe(3+)、N(-)和γ-Al2O3）的基于TiO2纳米颗粒的光催化剂，以及覆盖有超小金纳米颗粒（AuNPs）的光催化剂。通过在可见光照射下将它们用于模型染料亚甲基蓝（MB）的液相分解来研究其光催化性能。使用X射线衍射、X射线光电子能谱、漫反射紫外-可见吸收光谱、拉曼光谱和透射电子显微镜对光催化剂的结构、形态、物理化学和光学性质进行了研究。通过测量不同照射时间下MB在664nm处的吸光度来跟踪MB的光降解动力学，而通过测定总有机碳（TOC）含量来检查MB的矿化情况。通过向晶格中引入掺杂剂并在表面沉积AuNPs，TiO2纳米颗粒的光催化活性显著提高。其中，覆盖有沉积AuNPs的γ-Al2O3掺杂TiO2纳米颗粒表现出最佳的光催化性能。总之，这里制备的由用AuNPs修饰的掺杂TiO2纳米颗粒组成的光催化剂建立了新型的三元纳米复合体系，其中表面AuNPs、掺杂剂和TiO2之间的协同相互作用被证明显著提高了光催化活性。
