title: Alkylamine capped metal nanoparticle "inks" for printable SERS substrates, electronics and broadband photodetectors.
abstract: We report a facile and general method for the preparation of alkylamine capped metal (Au and Ag) nanoparticle "ink" with high solubility. Using these metal nanoparticle "inks", we have demonstrated their applications for large scale fabrication of highly efficient surface enhanced Raman scattering (SERS) substrates by a facile solution processing method. These SERS substrates can detect analytes down to a few nM. The flexible plastic SERS substrates have also been demonstrated. The annealing temperature dependent conductivity of the nanoparticle films indicated a transition temperature above which high conductivity was achieved. The transition temperature could be tailored to the plastic compatible temperatures by using proper alkylamine as the capping agent. The ultrafast electron relaxation studies of the nanoparticle films demonstrated that faster electron relaxation was observed at higher annealing temperatures due to stronger electronic coupling between the nanoparticles. The applications of these highly concentrated alkylamine capped metal nanoparticle inks for the printable electronics were demonstrated by printing the oleylamine capped gold nanoparticles ink as source and drain for the graphene field effect transistor. Furthermore, the broadband photoresponse properties of the Au and Ag nanoparticle films have been demonstrated by using visible and near-infrared lasers. These investigations demonstrate that these nanoparticle "inks" are promising for applications in printable SERS substrates, electronics, and broadband photoresponse devices.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543.
authors.forename: Lakshminarayana
authors.initials: L
authors.lastname: Polavarapu
authors.forename: Kiran Kumar
authors.initials: KK
authors.lastname: Manga
authors.forename: Kuai
authors.initials: K
authors.lastname: Yu
authors.forename: Priscilla Kailian
authors.initials: PK
authors.lastname: Ang
authors.forename: Hanh Duyen
authors.initials: HD
authors.lastname: Cao
authors.forename: Janardhan
authors.initials: J
authors.lastname: Balapanuru
authors.forename: Kian Ping
authors.initials: KP
authors.lastname: Loh
authors.forename: Qing-Hua
authors.initials: QH
authors.lastname: Xu
mesh_terms: D000588:Amines / Q000737:chemistry*; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D007281:Ink; D044085:Microfluidics / Q000379:methods; D010783:Photometry / Q000295:instrumentation*; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*
chemical_list: D000588:Amines; D012834:Silver; D006046:Gold