Tang Lanqin, Jia Yin, Zhu Zhishang, Hua Yue, Wu Jun, Zou Zhigang, Zhou Yong
College of Chemistry and Chemical Engineering, Yancheng Institute of Technology, 9 Yingbin Avenue, Yancheng 224051, China.
National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, School of Physics, Nanjing University, Nanjing 210093, China.
Molecules. 2022 Jan 27;27(3):833. doi: 10.3390/molecules27030833.
The present work reports on the synthesis of ZnO photocatalysts with different Co-doping levels via a facile one-step solution route. The structural and optical properties were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and UV-Vis diffuse reflectance spectra. The morphology of Co-doped ZnO depends on the reaction temperature and the amount of Co and counter-ions in the solution. Changes with the c-axis lattice constant and room temperature redshift show the replacement of Zn with Co ions without changing the wurtzite structure. Photocatalytic activities of Co-doped ZnO on the evolution of H and the degradation of methylene blue (MB) reduce with the doping of Co ions. As the close ionic radii of Co and Zn, the reducing photocatalytic activity is not due to the physical defects but the formation of deep bandgap energy levels. Photocurrent response experiments further prove the formation of the recombination centers. Mechanistic insights into Co-ZnO formation and performance regulation are essential for their structural adaptation for application in catalysis, energy storage, etc.
本工作报道了通过简便的一步溶液法合成不同钴掺杂水平的ZnO光催化剂。通过粉末X射线衍射（XRD）、场发射扫描电子显微镜（FESEM）、透射电子显微镜（TEM）、能量色散光谱（EDS）和紫外-可见漫反射光谱对其结构和光学性质进行了表征。钴掺杂ZnO的形貌取决于反应温度以及溶液中钴和抗衡离子的量。c轴晶格常数和室温红移的变化表明钴离子取代了锌离子，而纤锌矿结构未发生改变。钴掺杂ZnO对氢气析出和亚甲基蓝（MB）降解的光催化活性随着钴离子的掺杂而降低。由于钴和锌的离子半径相近，光催化活性降低并非由于物理缺陷，而是由于形成了深带隙能级。光电流响应实验进一步证明了复合中心的形成。深入了解钴-氧化锌的形成和性能调控机制对于其结构适配催化、储能等应用至关重要。
