Zhu Wei, Feng Xiaoqiang, Liu Zhiduo, Zhao Menghan, He Peng, Yang Siwei, Tang Shiwei, Chen Da, Guo Qinglei, Wang Gang, Ding Guqiao
Department of Microelectronic Science and Engineering, School of Physical Science and Technology, Ningbo University, Ningbo 315211, P. R. China.
State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China.
ACS Appl Mater Interfaces. 2021 May 19;13(19):23081-23091. doi: 10.1021/acsami.1c02182. Epub 2021 May 7.
Surface-enhanced Raman scattering (SERS) substrates based on graphene and its derivatives have recently attracted attention among those interested in the detection of trace molecules; however, these substrates generally show poor uniformity, an unsatisfactory enhancement factor, and require a complex fabrication process. Herein, we design and fabricate three-dimensional (3D) graphene/silicon (3D-Gr/Si) heterojunction SERS substrates to detect various types of molecules. Notably, the detection limit of 3D-Gr/Si can reach 10 M for rhodamine 6G (R6G) and rhodamine B (RB), 10 M for crystal violet (CRV), copper(II) phthalocyanine (CuPc), and methylene blue (MB), 10 M for dopamine (DA), 10 M for bovine serum albumin (BSA), and 10 M for melamine (Mel), which is superior to most reported graphene-based SERS substrates. Besides, the proposed 3D-Gr/Si heterojunction SERS substrates can achieve a high uniformity with relative standard deviations (RSDs) of less than 5%. Moreover, the 3D-Gr/Si SERS substrates are reusable after washing with ethyl alcohol to remove the adsorbed molecules. These excellent SERS performances are attributed to the novel 3D structure and abundantly exposed atomically thin edges, which facilitate charge transfer between 3D-Gr and probe molecules. We believe that the 3D-Gr/Si heterojunction SERS substrates offer potential for practical applications in biochemical molecule detection and provide insight into the design of high-performance SERS substrates.
基于石墨烯及其衍生物的表面增强拉曼散射（SERS）基底最近在痕量分子检测领域引起了关注；然而，这些基底通常表现出较差的均匀性、不理想的增强因子，并且需要复杂的制备工艺。在此，我们设计并制备了三维（3D）石墨烯/硅（3D-Gr/Si）异质结SERS基底用于检测各种类型的分子。值得注意的是，3D-Gr/Si对罗丹明6G（R6G）和罗丹明B（RB）的检测限可达10⁻⁸ M，对结晶紫（CRV）、铜（II）酞菁（CuPc）和亚甲基蓝（MB）为10⁻⁷ M，对多巴胺（DA）为10⁻⁶ M，对牛血清白蛋白（BSA）为10⁻⁵ M，对三聚氰胺（Mel）为10⁻⁴ M，这优于大多数已报道的基于石墨烯的SERS基底。此外，所提出的3D-Gr/Si异质结SERS基底可实现小于5%的相对标准偏差（RSD）的高均匀性。而且，3D-Gr/Si SERS基底在用乙醇洗涤以去除吸附分子后可重复使用。这些优异的SERS性能归因于新颖的3D结构和大量暴露的原子级薄边缘，这有利于3D-Gr与探针分子之间的电荷转移。我们相信3D-Gr/Si异质结SERS基底在生化分子检测的实际应用中具有潜力，并为高性能SERS基底的设计提供了思路。
