title: Identifying Enclosed Chemical Reaction and Dynamics at the Molecular Level Using Shell-Isolated Miniaturized Plasmonic Liquid Marble.
abstract: Current microscale tracking of chemical kinetics is limited to destructive ex situ methods. Here we utilize Ag nanocube-based plasmonic liquid marble (PLM) microreactor for in situ molecular-level identification of reaction dynamics. We exploit the ultrasensitive surface-enhanced Raman scattering (SERS) capability imparted by the plasmonic shell to unravel the mechanism and kinetics of aryl-diazonium surface grafting reaction in situ, using just a 2-μL reaction droplet. This reaction is a robust approach to generate covalently functionalized metallic surfaces, yet its kinetics remain unknown to date. Experiments and simulations jointly uncover a two-step sequential grafting process. An initial Langmuir chemisorption of sulfonicbenzene diazonium (dSB) salt onto Ag surfaces forms an intermediate sulfonicbenzene monolayer (Ag-SB), followed by subsequent autocatalytic multilayer growth of Ag-SB3. Kinetic rate constants reveal 19-fold faster chemisorption than multilayer growth. Our ability to precisely decipher molecular-level reaction dynamics creates opportunities to develop more efficient processes in synthetic chemistry and nanotechnology.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Han
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.|Institute of Materials Research and Engineering , Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis, #08-03, Singapore 138634.
authors.forename: Hiang Kwee
authors.initials: HK
authors.lastname: Lee
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Yih Hong
authors.initials: YH
authors.lastname: Lee
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798.
authors.forename: Wei
authors.initials: W
authors.lastname: Hao
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Yejing
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Materials Research and Engineering , Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis, #08-03, Singapore 138634.
authors.forename: In Yee
authors.initials: IY
authors.lastname: Phang
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798.
authors.forename: Shuzhou
authors.initials: S
authors.lastname: Li
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Xing Yi
authors.initials: XY
authors.lastname: Ling