论文标题
Tio $ _2 $表面脱水的Au纳米颗粒 - 与尺寸无关的等离子光电化学响应的证据
Dewetted Au nanoparticles on TiO$_2$ surfaces -- Evidence of a size-independent plasmonic photo-electrochemical response
论文作者
论文摘要
平坦Tio $ _2 $层是通过木量溅射在ti/si wafers上存放的。然后将Tio $ _2 $表面用薄膜刺覆，名义厚度为0.5-10 nm，通过固态露水转换为可调尺寸和间距的Au纳米颗粒； Au纳米颗粒的大小可以在广泛的范围内进行调整，即CA。 3-200 nm。 Au装饰的TiO $ _2 $表面在可见光照明下（450-750 nm）下启用等离子光电化学水分裂。水分拆分性能达到了用约30 nm尺寸的AU颗粒装饰的TIO $ _2 $层的最大值。如预期的那样，光吸收测量结果表明，随着Au纳米颗粒尺寸的增加，等离子灭绝带的红移。然而，发现等离子光电流在〜600 nm处达到峰值，而不管Au纳米颗粒的大小如何，即等离子光电流带位置是无关的。这样的显着观察可以归因于热电子注入临界效应。
Flat TiO$_2$ layers are deposited by magnetron sputtering on Ti/Si wafers. The TiO$_2$ surfaces are then sputter-coated with thin Au films of a nominal thickness of 0.5-10 nm that are converted by solid-state dewetting into Au nanoparticles of tuneable size and spacing; the Au nanoparticle size can be tuned over a broad range, i.e. ca. 3-200 nm. The Au-decorated TiO$_2$ surfaces enable plasmonic photo-electrochemical water splitting under visible light illumination (450-750 nm). The water splitting performance reaches a maximum for TiO$_2$ layers decorated with ~ 30 nm-sized Au particles. As expected, optical absorption measurements show a red shift of the plasmonic extinction band with increasing the Au nanoparticle size. However, the plasmonic photocurrent is found to peak at ~ 600 nm regardless of the size of the Au nanoparticles, i.e. the plasmonic photocurrent band position is size-independent. Such a remarkable observation can be ascribed to a hot electron injection cut-off effect.
