Abstract Energy level alignment at the interface of ZnO with monolayer sheets of graphene oxide (GO), reduced graphene oxide (RGO), and simultaneously reduced and doped graphene oxide by ammonia plasma treatment (APGO/ZnO) have been investigated using the photoelectron spectroscopy. The difference in surface sensitivity of XPS and UPS has been utilized to deduce the energy band diagram. The measurements reveal band bending, charge transfer and dipole formation at the interfaces. GO/ZnO and RGO/ZnO interfaces show dipole formation attributable primarily to interfacial charge transfer. In contrast, APGO/ZnO interface shows insignificant charge transfer and the energy level alignment being determined primarily by the doping of GO and ZnO and geometrical/structural changes in the later. The study facilitates improved understanding of the electronic structure of the interfaces of ZnO with GO and its derivatives and may be useful for designing efficient charge transport in such heterostructures.

中文翻译：

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氧化石墨烯及其衍生物与 ZnO 的能级排列

摘要 使用光电子能谱研究了 ZnO 与单层氧化石墨烯 (GO)、还原氧化石墨烯 (RGO) 以及通过氨等离子体处理同时还原和掺杂氧化石墨烯 (APGO/ZnO) 的界面处的能级排列。XPS 和 UPS 的表面灵敏度差异已被用来推导出能带图。测量结果揭示了界面处的带弯曲、电荷转移和偶极子形成。GO/ZnO 和 RGO/ZnO 界面显示偶极子形成主要归因于界面电荷转移。相比之下，APGO/ZnO 界面显示出微不足道的电荷转移，能级排列主要由 GO 和 ZnO 的掺杂以及后者的几何/结构变化决定。