Bulusheva L G, Arkhipov V E, Popov K M, Sysoev V I, Makarova A A, Okotrub A V
Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Acad. Lavrentiev Ave., Novosibirsk 630090, Russia.
Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090, Russia.
Materials (Basel). 2020 Mar 6;13(5):1173. doi: 10.3390/ma13051173.
Heteroatom doping is a widely used method for the modification of the electronic and chemical properties of graphene. A low-pressure chemical vapor deposition technique (CVD) is used here to grow pure, nitrogen-doped and phosphorous-doped few-layer graphene films from methane, acetonitrile and methane-phosphine mixture, respectively. The electronic structure of the films transferred onto SiO/Si wafers by wet etching of copper substrates is studied by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy using a synchrotron radiation source. Annealing in an ultra-high vacuum at ca. 773 K allows for the removal of impurities formed on the surface of films during the synthesis and transfer procedure and changes the chemical state of nitrogen in nitrogen-doped graphene. Core level XPS spectra detect a low -type doping of graphene film when nitrogen or phosphorous atoms are incorporated in the lattice. The electrical sheet resistance increases in the order: graphene < P-graphene < N-graphene. This tendency is related to the density of defects evaluated from the ratio of intensities of Raman peaks, valence band XPS and NEXAFS spectroscopy data.
杂原子掺杂是一种广泛用于修饰石墨烯电子和化学性质的方法。本文采用低压化学气相沉积技术（CVD），分别以甲烷、乙腈和甲烷 - 膦混合物为原料，生长纯的、氮掺杂和磷掺杂的少层石墨烯薄膜。通过使用同步辐射源的X射线光电子能谱（XPS）和近边X射线吸收精细结构（NEXAFS）光谱，研究了通过湿法蚀刻铜衬底转移到SiO/Si晶片上的薄膜的电子结构。在约773K的超高真空下退火，可以去除合成和转移过程中在薄膜表面形成的杂质，并改变氮掺杂石墨烯中氮的化学状态。当氮或磷原子掺入晶格中时，芯能级XPS光谱检测到石墨烯薄膜的低型掺杂。薄膜的面电阻按以下顺序增加：石墨烯<P - 石墨烯<N - 石墨烯。这种趋势与根据拉曼峰强度比、价带XPS和NEXAFS光谱数据评估的缺陷密度有关。
