Ag/Au Alloy LSPR Engineering by Co‐deposition of RF‐Sputtering and RF‐PECVD

Abstract

Silver-Gold alloy/diamond like carbon (Ag-Au/DLC) nanocomposite films were prepared by co-deposition of RF-sputtering and RF-PECVD on glass substrates by using acetylene gas and silver-gold target. The deposition process was carried out at room temperature in one minute with the variable parameters of initial pressures and RF powers. X-ray diffraction analysis demonstrated the formation of Ag/Au alloy nanoparticles with a face-centered cubic (FCC) structure.Localized surface plasmon and optical properties of Ag-Au alloy nanoparticles were studied by UV-visible spectrophotometry which showed that increasing RF power and initial pressure cause a redshift in all samples. Moreover, the effect of RF power and initial pressure on the size and shape of nanoparticles were studied by 2D Atomic force microscopy images. Energy dispersive X-ray spectroscopy revealed the formation of Ag-Au/DLC nanoparticles and the percentages of C, Ag, Au and O in all samples. The applied method for Ag/Au alloy preparation is the one step and low-cost method which makes the samples ready for sensing application.

Sputtering onto a liquid: interesting physical preparation method for multi-metallic nanoparticles

“…As a conventional approach for producing thin film and multiple layers of metals, metal alloys, and metal oxides the method still received significant studies until now [5][6][7][8][9][10][11][12][13][14][15][16]. To some extent, the technique has been also used for immobilizing nanoparticles (NPs) on a solid substrate [17][18][19][20][21][22], or decorating nanoparticles on other metal/oxides nano-micron particles as the supporters [23][24][25][26][27][28][29][30][31][32][33]. In order to have NPs instead of big aggregate or thin film very short sputtering time, that is in order of few to several tens of second [23,27], or low pressure [24,25,27] or post heat-treatment [29,30] has been used.…”

“…Thus, it is challenging to create conditions favourable for co-reduction and alloying rather than for heterogeneous structure formation. Sputtering techniques, on the other hand, can produce atoms or clusters of any metal at once by the physical bombardment of energetic gas ions onto metal targets [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. This can allow for the production of alloy NPs of various bimetallic systems.…”