Synergistic enhancement effect of MoO3@Ag hybrid nanostructures for boosting selective detection sensitivity

Tengda Shi; Pei Liang; Xiubing Zhang; De Zhang; Haibo Shu; Jie Huang; Zhi Yu; YongQuan Xu

doi:10.1016/j.saa.2020.118611

Synergistic enhancement effect of MoO₃@Ag hybrid nanostructures for boosting selective detection sensitivity

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Nov 5:241:118611. doi: 10.1016/j.saa.2020.118611. Epub 2020 Jun 18.

Authors

Tengda Shi¹, Pei Liang², Xiubing Zhang¹, De Zhang³, Haibo Shu¹, Jie Huang¹, Zhi Yu³, YongQuan Xu⁴

Affiliations

¹ College of Optical and Electronic Technology, China Jiliang University, 310018 Hangzhou, China.
² College of Optical and Electronic Technology, China Jiliang University, 310018 Hangzhou, China. Electronic address: plianghust@gmail.com.
³ College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Key Laboratory of Horticultural Plant Biology, Ministry of Education, 430070 Wuhan, China.
⁴ Tea Research Institute Chinese Academy of Agricultural Sciences, National Engineering Research Center for Tea Processing, Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, 9 South Meiling Road, Hangzhou 310008, China.

PMID: 32619971
DOI: 10.1016/j.saa.2020.118611

Abstract

An ex situ method was used to synthesize noble metals and metal oxide composite materials, due to the selective adsorption properties of metal oxides, the adsorption of different probe molecules by this composite structure had been studied. In the ex situ approach, we use (3-aminopropyl) diethoxy methylsilane (ATES) as a coupling agent which is easy for noble metal nanoparticles deposited on metallic oxide nanomaterials. The Raman scattering (SERS) substrate of 1D MoO₃ nanowires (MoO₃-NWs) @Ag nanoparticles (Ag-NPs) hybrid surface had been fabricated. Several parameters are presented in the following which influences the morphology of self-assembly and SERS activity: (i) coupling agent of ATES, (ii) ATES content (iii) Ag-NPs content. The finite difference time domain (FDTD) method is to explain the enhancement mechanism distribution of the hybrid substrate. Different probe molecules (R6G, Methylene Blue, Crystal Violet, and 4-ATP) have been adsorbed for SERS tests. Improved principle component analysis (PCA) is adopted to obtain the minimum detection limit of probe molecules. Through the DFT calculation, different absorption strengths between the target molecules and the MoO₃(010) surface have been illustrated, which is also the main reason for the selective enhancement effect of MoO₃@Ag hybrid nanostructures. This paper might propose a method to prepare such enhancement substrate based on the selective absorption properties of oxide semiconductors.

Keywords: DFT; FDTD; MoO(3)@Ag hybrid nanostructures; SERS; Selective SERS enhancement effect.