Surface plasmon resonance of gold nanoparticles formed by cathodic arc plasma ion implantation into polymer

Abstract

Shallow subsurface layers of gold nanoclusters were formed in polymethylmethacrylate ͑PMMA͒ polymer by very low energy ͑49 eV͒ gold ion implantation. The ion implantation process was modeled by computer simulation and accurately predicted the layer depth and width. Transmission electron microscopy ͑TEM͒ was used to image the buried layer and individual nanoclusters; the layer width was ϳ6-8 nm and the cluster diameter was ϳ5-6 nm. Surface plasmon resonance ͑SPR͒ absorption effects were observed by UV-visible spectroscopy. The TEM and SPR results were related to prior measurements of electrical conductivity of Au-doped PMMA, and excellent consistency was found with a model of electrical conductivity in which either at low implantation dose the individual nanoclusters are separated and do not physically touch each other, or at higher implantation dose the nanoclusters touch each other to form a random resistor network ͑percolation model͒.

Structure of disordered gold-polymer thin films using small angle x-ray scattering

“…Gold ions were subplanted into the PMMA surface. In previous work, we have investigated the subplanted material using transmission electron microscopy ͑TEM͒ and we have found 16 below the surface. We have also carried out Monte-Carlo computer simulations of low energy implantation and found 13 good agreement with the TEM data.…”

“…Ion implantation was done using a repetitively pulsed cathodic arc plasma gun, described in detail elsewhere, 10,13,16,29,30 which produces a unidirectional stream of fully ionized metal plasma ͑in this case gold plasma͒ in pulses of duration 5 ms at a repetition rate of 1 Hz. Base pressure in the vacuum chamber was 6 ϫ 10 −6 Torr ͑ϳ8 ϫ 10 −4 Pa͒.…”

“…The cluster size is about 6 nm. 16 The formation and characteristics of gold nanoclusters are a current research issue because of their potential application in areas such as photonics and biosensing. [17][18][19][20][21][22] We chose PMMA polymer in our work because of its good optical and dielectric properties and because it immediately passivates the implanted ions.…”

Cell adhesion and growth on surfaces modified by plasma and ion implantation

“…16 Silver nanoparticles are known for their antibacterial properties. 17 As it is known that implantation of metal into polymer using ion implantation forms nanoparticles inside the polymer, [18][19][20][21][22][23][24][25][26] we evaluated the cell growth on buried silver nanoparticles into SU-8 formed by ion implantation. PDMS is a widely used polymeric material with several interesting characteristics, which include high flexibility, optical transparency, biocompatibility, and ease to fabricate.…”

Testes e aplicação de um novo implantador iônico.

“…Os métodos físicos incluem a ablação por laser, deposição química a vapor, fluidos supercríticos dentre outros [39]. A implantação iônica também tem sido utilizada para gerar camada de nanocompósito alguns nanômetros abaixo da superfície do substrato [12,[40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Como já mencionado no Capítulo 2, a formação das nanopartículas metálicas se dá espontaneamente e pode ser explicada pela ocorrência de concentração dos átomos metálicos acima do limite de solubilidade no substrato implantado, levando à nucleação e crescimento das nanopartículas metálicas [27].…”