石墨烯对ZnO微米棒光学特性的影响

采用化学气相沉积(CVD)方法制备了具有良好结晶质量和(002)择优取向的ZnO微米棒。在此基础上,选取单根ZnO微米棒,将其部分搁置于单层石墨烯表面。光致发光(PL)谱结果表明,石墨烯不仅增强了ZnO微米棒的紫外发光强度,同时也对光场在ZnO微米棒中的分布有很大的限域作用。分析认为这是由于石墨烯的表面等离子效应引起了ZnO微米棒与石墨烯之间的光-物质相互作用导致的。在拉曼(Raman)光谱中,石墨烯对ZnO微米棒的E2(L)声子振动模和E2(H)声子振动模的强度具有明显的减弱效应,这进一步证明二者之间存在光子的传输和电荷的转移,从而导致其晶格振动受到抑制。

Abnormal Optical Properties in ZnO Mircorods Introduced by Graphene

High crystal quality and (002) orientation preferred ZnO microrods were grown by the method of chemical vapor deposition (CVD). The optical properties of ZnO microrod on graphene substrate were investigated. The photoluminescence (PL) spectra revealed that the luminous intensity of ZnO microrod on graphene substrate was enhanced as twice as that without graphene substrate. The distribution of light field in ZnO microrod was also restricted by graphene. These are all caused by grapheme surface plasmon. In the case of ZnO microrod on the graphene substrate, E₂(L) and E₂(H) Raman intensity decreased dramatically by comparing with which of the ZnO microrod without graphene substrate. This further indicates that there is stronger light-matter interaction at the interface. Hence, the lattice vibration of ZnO microrod was restricted by the graphene.