119th General Meeting of the KCS

Type Poster Presentation
Area 물리화학
Room No. 포스터발표장
Time 4월 20일 (목요일) 11:00~12:30
Code PHYS.P-18
Subject Facile self-assembly of silver nanoprisms using polypyrrole for enhanced stability and optical properties
Authors 정동원, 장두전*
서울대학교 화학부, Korea
Abstract Silver nanoprisms (AgPRs) have been widely investigated for applications such as solar cells, catalysis, and sensing due to massive electromagnetic field enhancement and high sensitivity, which are attributed to the sharp tips of AgPRs. Herein, we are reporting a one-step polypyrrole (PPy) coating process of self-assembled silver nanoprisms (AgPRs) through the direct polymerization of pyrrole (Py) monomers that also act as an assembling agent. The assemblies of AgPRs, whose edge lengths and thicknesses are typically 78 and 6 nm, have been surrounded by PPy coating of 6 nm. AgPRs are assembled in an edge-to-edge orientation, and the degree of assembly has been controlled by varying the concentration of trisodium citrate which attaches selectively to the {111} facets of AgPRs. Furthermore, the increased red shift of surface-plasmon resonances beyond 930 nm upon increase of the TSC concentration has suggested that the assembly degree of AgPRs can be controlled by varying the concentration of TSC. The morphology deformation time of PPy-coated AgPRs in 0.6 mM H2O2(aq) is 7 times longer than that of PPy-free AgPRs, suggesting that PPy coating prevents the sharp tips of AgPRs from being truncated by oxidizing agents. The SERS effect of highly self-assembled and PPy-coated AgPRs becomes as high as 6.3 due to numerous hot spots generated between nanoprisms. Overall, we fabricated AgPRs assemblies with PPy coating which have not only improved structural stability but also enhanced optical properties.
E-mail 37kevin2@snu.ac.kr