Citation: Jiao, S.; Liu, Y.; Wang, S.;
Wang, S.; Ma, F.; Yuan, H.; Zhou, H.;
Zheng, G.; Zhang, Y.; Dai, K.; et al.
Face-to-Face Assembly of Ag
Nanoplates on Filter Papers for
Pesticide Detection by
Surface-Enhanced Raman
Spectroscopy. Nanomaterials 2022, 12,
1398. https://doi.org/10.3390/
nano12091398
Academic Editors: Ki-Hyun Kim and
Deepak Kukkar
Received: 10 March 2022
Accepted: 6 April 2022
Published: 19 April 2022
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Article
Face-to-Face Assembly of Ag Nanoplates on Filter Papers for
Pesticide Detection by Surface-Enhanced Raman Spectroscopy
Sulin Jiao
1,2,3,†
, Yixin Liu
3,†
, Shenli Wang
4,†
, Shuo Wang
1,2
, Fengying Ma
3
, Huiyu Yuan
5
, Haibo Zhou
6,
* ,
Guangchao Zheng
3,
*, Yuan Zhang
3,
*, Kun Dai
1,2,
* and Chuntai Liu
1,2
1
School of Materials Science and Engineering, Key Laboratory of Materials Processing and Mold
(Zhengzhou University), Ministry of Education, Zhengzhou 450001, China; jzr1771516@163.com (S.J.);
18860365730@163.com (S.W.); ctliu@zzu.edu.cn (C.L.)
2
Henan Key Laboratory of Advanced Nylon Materials and Application (Zhengzhou University),
Zhengzhou University, Zhengzhou 450001, China
3
Key Laboratory of Material Physics, School of Physics and Microelectronics, Ministry of Education,
Zhengzhou University, Zhengzhou 450001, China; lyx_zzu@163.com (Y.L.); mafy@163.com (F.M.)
4
School of Food Science and Engineering, Henan University of Technology, Lianhua Road 100,
Zhengzhou 450001, China; wangshenli@126.com
5
Henan Key Laboratory of High Temperature Functional Ceramics, School of Materials Science and
Engineering, Zhengzhou University, Zhengzhou 450001, China; hyyuan@zzu.edu.cn
6
Institute of Pharmaceutical Analysis, College of Pharmacy, Jinan University, Guangzhou 510632, China
* Correspondence: zhengguangchao2008@gmail.com (H.Z.); yzhuaudipc@zzu.edu.cn (G.Z.);
kundai@zzu.edu.cn (Y.Z.); haibo.zhou@jnu.edu.cn (K.D.)
† These authors contributed equally to this work.
Abstract:
Surface-enhanced Raman spectroscopy (SERS) technology has been regarded as a most
efficient and sensitive strategy for the detection of pollutants at ultra-low concentrations. Fabrication
of SERS substrates is of key importance in obtaining the homogeneous and sensitive SERS signals.
Cellulose filter papers loaded with plasmonic metal NPs are well known as cost-effective and
efficient paper-based SERS substrates. In this manuscript, face-to-face assembly of silver nanoplates
via solvent-evaporation strategies on the cellulose filter papers has been developed for the SERS
substrates. Furthermore, these developed paper-based SERS substrates are utilized for the ultra-
sensitive detection of the rhodamine 6G dye and thiram pesticides. Our theoretical studies reveal the
creation of high density hotspots, with a huge localized and enhanced electromagnetic field, near the
corners of the assembled structures, which justifies the ultrasensitive SERS signal in the fabricated
paper-based SERS platform. This work provides an excellent paper-based SERS substrate for practical
applications, and one which can also be beneficial to human health and environmental safety.
Keywords: SERS 1; face-to-face assembly 2; Ag nanoplates 3; chemical sensing 4
1. Introduction
Surface-enhanced Raman spectroscopy (SERS) is one promising surface precautionary
technology for the selective and sensitive detection of analytic molecules in the field of
human health and environmental safety [
1
]. Even an ultra-low concentration of target
analytes can be harmful or deadly for the environment and living system. Therefore,
the development of stable, portable, and sensitive technology is urgently required for
the fingerprint identification of target molecules. The non-destructive, rapid, and label-
free characteristics of SERS make it to well-suited to meeting this practical need. One
cornerstone of SERS is its ability to probe Raman scattering of molecules nearby or on
the surface of plasmonic metal nanoparticles (NPs). The well-reorganized chemical and
physical enhancements in SERS are due to the mechanisms of charge transfer and localized
electromagnetic field (EF) enhancement, respectively [2–5].
Nanomaterials 2022, 12, 1398. https://doi.org/10.3390/nano12091398 https://www.mdpi.com/journal/nanomaterials
