摘要
As a powerful non-destructive and label-free detection technology,surface-enhanced Raman scattering(SERS)has been widely used in environmental-pollutant detection,biological-tissue sensing,molecular fingerprint analysis and so on.Different from the traditional SERS substrates represented by noble metals and semiconductors,herein,we report a new highly sensitive SERS substrate material with high stability,biocompatibility,and low cost,namely nucleusfree two-dimensional electron gas(2DEG)Ti3C2 monolayer nanosheets.The highly crystalline monolayer Ti3C2 nanosheets with clean surface are synthesized by an improved chemical exfoliation and microwave heating method.The unique structure of nucleus-free-2DEG in Ti3C2 monolayer provides an ideal transport channel without nuclear scattering,which makes the highly crystalline monolayer Ti3C2 nanosheets achieve a Raman enhanced factor of 3.82×108 and a 10-11 level detection limit for typical environmental pollutants such as azo dyes,trichlorophenol,and bisphenol A.Singlemolecule imaging is also realized on the surface of the Ti3C2 monolayers,which may be the first time that approximate single-molecule imaging has been achieved on a non-noblemetal SERS substrates.Preliminary toxicological experiments show that the cytotoxicity of this material is very low.Considering the facile synthesis,high biocompatibility,low cost and high chemical stability of carbide nanosheets,these Ti3C2 monolayer nanosheets show significant promise for the design and fabrication of flexible SERS substrates for the sensing of trace substances with ultrahigh sensitivity.
表面增强拉曼散射(SERS)作为一种优秀的免标记无损检测技术,已被广泛应用于环境污染物检测、生物组织传感及指纹级分子分析等领域.与以贵金属和半导体为代表的传统SERS基底不同,本文报道了一种新型的高灵敏SERS基底材料,即无核二维电子气(2DEG)结构的Ti3C2单层纳米片,其具有高稳定性、生物相容性和低成本等优点.我们通过一种化学剥离和微波加热相结合的方法合成了具有洁净表面的、高度结晶的单层Ti3C2纳米片.Ti3C2单层无核2DEG的独特电子结构提供了理想的无核散射传输通道,使单层Ti3C2纳米片的拉曼增强因子达到了3.82×108,其对典型污染物的检出限高达10-11mol L-1.初步的毒理学实验表明,该物质的细胞毒性非常低.考虑到碳化物纳米片合成简单、良好的生物相容性、低成本以及高的化学稳定性,Ti3C2单层对于设计和制造具有超高灵敏度的柔性SERS衬底具有很好的应用前景.
作者
Yuting Ye
Wencai Yi
Wei Liu
Yun Zhou
Hua Bai
Junfang Li
Guangcheng Xi
叶雨庭;易文才;刘伟;周云;白桦;李俊芳;席广成(Institute of Industrial and Consumer Product Safety,Chinese Academy of Inspection and Quarantine,Beijing 100176,China;School of Physics and Physical Engineering,Qufu Normal University,Qufu 273165,China;College of Science,Chinese Jiliang University,Hangzhou 310018,China)
基金
support from the Science Foundation of Chinese Academy of Inspection and Quarantine(2019JK004)
the National Key Research and Development Program of China(2017YFF0210003)
the high performance computing center of Qufu Normal University。
作者简介
Yuting Ye,is currently a MSc candidate in material chemistry under the supervision of Prof.Guangcheng Xi at Chinese Academy of Inspection and Quarantine.His research centers on developing the excellent SERS materials for chemical sensing devices;Wencai Yi,received his BSc degree in 2013 from Tianjin Normal University.In 2018,he received his PhD degree from Jilin University,China.Then,he joined Qufu Normal University as a lecturer.His research interests focus on the algorithm of structure prediction,low dimensional gas-sensing materials,SERS and high energy density materials;Corresponding author:Guangcheng Xi,received his BSc degree in 2002 from Fuyang Normal University,China.In 2007,he received his PhD degree from the University of Science and Technology of China.Then,he joined Chinese Academy of Inspection and Quarantine as an assistant professor.He became an associate professor in 2011 and a full professor in 2017.Currently,his research interests focus on the SERS,chemical sensing,and the nanostructure-based analysis for harmful substances(email:xiguangcheng@caiq.org.cn)。
