Lu Yangfan, Li Dongsheng, Liu Fu
School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
College of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China.
Materials (Basel). 2022 Jan 2;15(1):307. doi: 10.3390/ma15010307.
Angle-resolved XPS combined with argon ion etching was used to characterize the surface functional groups and the chemical structure of TiCT MXene. Survey scanning obtained on the sample surface showed that the sample mainly contains C, O, Ti and F elements, and a little Al element. Analyzing the angle-resolved narrow scanning of these elements indicated that a layer of C and O atoms was adsorbed on the top surface of the sample, and there were many O or F related Ti bonds except Ti-C bond. XPS results obtained after argon ion etching indicated staggered distribution between C-Ti-C bond and O-Ti-C, F-Ti bond. It is confirmed that Ti atoms and C atoms were at the center layer of TiCT MXene, while O atoms and F atoms were located at both the upper and lower surface of TiC layer acting as surface functional groups. The surface functional groups on the TiC layer were determined to include O, OH, F and O-F, among which F atoms could also desorb from TiCT MXene easily. The schematic atomic structure of TiCT MXene was derived from the analysis of XPS results, being consistent with theoretical chemical structure and other experimental reports. The results showed that angle-resolved XPS combing with argon ion etching is a good way to analysis 2D thin layer materials.
采用角分辨X射线光电子能谱（Angle-resolved XPS）结合氩离子刻蚀对TiCT MXene的表面官能团和化学结构进行表征。在样品表面进行的全扫描显示，样品主要含有C、O、Ti和F元素，还有少量Al元素。对这些元素的角分辨窄扫描分析表明，样品顶表面吸附有一层C和O原子，除Ti-C键外，还有许多与O或F相关的Ti键。氩离子刻蚀后获得的XPS结果表明，C-Ti-C键与O-Ti-C、F-Ti键呈交错分布。证实Ti原子和C原子位于TiCT MXene的中心层，而O原子和F原子位于TiC层的上下表面，作为表面官能团。确定TiC层上的表面官能团包括O、OH、F和O-F，其中F原子也容易从TiCT MXene上解吸。TiCT MXene的示意性原子结构是通过对XPS结果的分析得出的，与理论化学结构和其他实验报告一致。结果表明，角分辨XPS结合氩离子刻蚀是分析二维薄层材料的一种好方法。
