Aimaganbetov Kazybek, Almas Nurlan, Kurbanova Bayan, Muratov Dauren, Serikkanov Abay, Insepov Zinetula, Tokmoldin Nurlan
Institute of Physics and Technology, Satbayev University, Almaty 050032, Kazakhstan.
Department of Science and Innovation, Astana IT University, Nur-Sultan 010000, Kazakhstan.
Materials (Basel). 2022 Aug 3;15(15):5330. doi: 10.3390/ma15155330.
Despite the impressive performance and incredible promise for a variety of applications, the wide-scale commercialization of graphene is still behind its full potential. One of the main challenges is related to preserving graphene's unique properties upon transfer onto practically desirable substrates. In this work, few-layer graphene sheets deposited via liquid-phase transfer from copper onto a quartz substrate have been studied using a suite of experimental techniques, including scanning electron microscopy (SEM), Raman spectroscopy, admittance spectroscopy, and four-point probe electrical measurements. SEM measurements suggest that the transfer of graphene from copper foil to quartz using the aqueous solution of ammonium persulfate was accompanied by unintentional etching of the entire surface of the quartz substrate and, as a result, the formation of microscopic facet structures covering the etched surface of the substrate. As revealed by Raman spectroscopy and the electrical measurements, the transfer process involving the etching of the copper foil in a 0.1 M solution of (NH)SO resulted in its p-type doping. This was accompanied by the appearance of an electronic gap of 0.022 eV, as evidenced by the Arrhenius analysis. The observed increase in the conductance of the samples with temperature can be explained by thermally activated carrier transport, dominating the scattering processes.
尽管石墨烯在各种应用中表现出色且前景广阔，但它的大规模商业化仍未完全发挥其潜力。主要挑战之一在于将石墨烯转移到实际所需的衬底上时，如何保持其独特性能。在这项工作中，我们使用了一系列实验技术，包括扫描电子显微镜（SEM）、拉曼光谱、导纳光谱和四点探针电学测量，对通过液相转移从铜转移到石英衬底上的少层石墨烯片进行了研究。SEM测量表明，使用过硫酸铵水溶液将石墨烯从铜箔转移到石英上时，石英衬底的整个表面会被意外蚀刻，结果在蚀刻后的衬底表面形成了微观小面结构。拉曼光谱和电学测量结果显示，在0.1 M的(NH)₂SO₄溶液中蚀刻铜箔的转移过程导致了其p型掺杂。正如阿仑尼乌斯分析所证明的，这伴随着0.022 eV的电子能隙出现。样品电导率随温度的升高可由热激活载流子输运来解释，热激活载流子输运主导了散射过程。
