Guo Shuang, Jin Sila, Park Eungyeong, Chen Lei, Mao Zhu, Jung Young Mee
Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon 24341, Korea.
Key Laboratory of Preparation and Applications of Environmental Friendly Materials (Jilin Normal University), Ministry of Education, Changchun 130103, P. R. China.
ACS Appl Mater Interfaces. 2021 Feb 3;13(4):5699-5705. doi: 10.1021/acsami.0c17056. Epub 2021 Jan 20.
Understanding and controlling the disorder in materials, especially the disorder caused by structural composition and doping effects, are important keys to studying the optical characteristics of materials. In this study, a SiO-Ag-reduced graphene oxide (rGO) composite structure was prepared by a simple wet chemical method, in which Ag nanoparticles (NPs) and SiO were decorated onto the surface of rGO. The introduction of Si atoms can control not only the plasmon effect of Ag NPs but also, more importantly, the defect concentration of rGO. The formation of defects causes the rGO structure to enter a metastable state, which facilitates charge separation and transfer in the system. It is worth noting that changes in defect concentration can affect the energy band position of rGO; therefore, controlling the defect concentration can be used to achieve charge transfer resonance coupling. This study not only revealed the ultrahigh surface-enhanced Raman scattering activity of the substrate structure but also elucidated in detail the effect of the crystallinity of this rGO-based composite system on its optical properties.
理解并控制材料中的无序状态，尤其是由结构组成和掺杂效应引起的无序，是研究材料光学特性的重要关键。在本研究中，通过简单的湿化学方法制备了SiO-Ag-还原氧化石墨烯（rGO）复合结构，其中Ag纳米颗粒（NPs）和SiO被修饰在rGO表面。Si原子的引入不仅可以控制Ag NPs的等离子体效应，更重要的是还可以控制rGO的缺陷浓度。缺陷的形成使rGO结构进入亚稳态，这有利于系统中的电荷分离和转移。值得注意的是，缺陷浓度的变化会影响rGO的能带位置；因此，控制缺陷浓度可用于实现电荷转移共振耦合。本研究不仅揭示了基底结构的超高表面增强拉曼散射活性，还详细阐明了这种基于rGO的复合系统的结晶度对其光学性质的影响。
