Unveiling the SERS activity of silver triangular nanoplates in the enhanced detection of 4-mercaptobenzoic acid

• Main Authors: Anh, Mai Ngoc Tuan, Nguyen, Dinh Tien Dung, Ching, Yern Chee, Thanh, Ngo Vo Ke, Phong, Nguyen Thi Phuong, Nguyen, Dai Hai, Bui, Bao Truc, Nguyen-Le, Minh-Tri
• Format: Article
• Published: Elsevier GmbH 2021
• Subjects: TP Chemical technology
• Online Access: http://eprints.um.edu.my/35927/; https://www.scopus.com/inward/record.uri?eid=2-s2.0-85117781507&doi=10.1016%2fj.ijleo.2021.168155&partnerID=40&md5=3ca6232883f504c9d59228b18a310ef5

Silver triangular nanoplates (SNPs) have gained much attraction worldwide due to their unique optical properties. In our study, we investigated the growth of SNPs via a modified seed-mediated method with NaBH4 as a primary reductant, ascorbic acid (AA) as a secondary reductant and H2O2 as a seed corrosive agent. It was found that small sized spherical seeds with low surface plasmon resonance were obtained in the presence of H2O2. The seed size played a key role for SNPs formation. SNPs size was found to be proportional to the seed size. The experimental results also provided the missing piece of role of AA in the formation of SNPs. The effects of AA on the formation of SNPs in the presence of H2O2 and without H2O2 were investigated via SEM, TEM and UV–Vis measurements. For each case, increasing AA content up to AA:Ag+ ratio of 1.0 would result in increasing the SNPs size and their uniformity. Above that ratio, smaller sized and less uniform SNPs were observed. Smaller sized SNPs fabricated by a seed-mediated method in the presence of H2O2 exhibit stronger SERS enhancement of 4-mercaptobezoic acid than those without H2O2. © 2021 Elsevier GmbH