Improved Photocatalytic Performance of the Ultra-small Ag Nanocrystallite-Decorated TiO2 Hollow Sphere Heterostructures
Publication in refereed journal

香港中文大學研究人員

引用次數
替代計量分析
.

其它資訊
摘要The ultra-small Ag nanocrystallite-decorated TiO2 hollow sphere heterostructures were fabricated by using a two-step hydrothermal method. These heterostructures demonstrated an excellent photodegradation performance of rhodamine B. The photodegradation efficiency could reach up to 100% within 20min under simulated sunlight irradiation. XRD, field emission SEM, TEM, scanning TEM, high-resolution TEM coupled with energy-dispersive X-ray spectroscopy, UV/Vis absorption and photoluminescence spectroscopy, X-ray photoelectron spectroscopy, Mott-Schottky analysis, and hydroxyl radical measurements were used to correlate the structure, surface property, and energy band alignment of rhodamine B to its photocatalytic activity. In these metal-semiconductor heterostructures, the Ag nanocrystallites were highly crystalline and were distributed evenly on the surface of TiO2 hollow spheres with compact interfaces. They reduced the recombination rate of charge carriers and favoured the charge transfer across the interfaces. The increased surface adsorbed oxygen facilitated the generation of hydroxyl radicals, and the reduced surface defects increased the lifetime of charge carriers upon Ag loading. The Schottky barriers between Ag and illuminated TiO2, the upward shift of the Fermi level, and increased electron density due to Ag coupling contributed to the charge transfer and increase in quantum efficiency. These key factors involved in photocatalysis are of great importance to design functional and effective photocatalysts.
著者Li Q, Zhang CH, Ma JM, Wang GZ, Ng DHL
期刊名稱ChemCatChem
出版年份2014
月份5
日期1
卷號6
期次5
出版社Wiley: 12 months
頁次1392 - 1400
國際標準期刊號1867-3880
電子國際標準期刊號1867-3899
語言英式英語
關鍵詞Ag; hollow sphere; metal-semiconductor; photocatalysis; TiO2
Web of Science 學科類別Chemistry; Chemistry, Physical; CHEMISTRY, PHYSICAL

上次更新時間 2021-15-04 於 23:05