TY - JOUR
T1 - Morphological and optical properties of PdxAg1-x alloy nanoparticles
AU - Kunwar, Sundar
AU - Pandey, Puran
AU - Sui, Mao
AU - Bastola, Sushil
AU - Lee, Jihoon
N1 - Publisher Copyright:
© 2018 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis.
PY - 2018/12/31
Y1 - 2018/12/31
N2 - Alloy nanoparticles (NPs) can offer a wide range of opportunities for various applications due to their composition and structure dependent properties such as multifunctionality, electronic heterogeneity, site-specific response, and multiple plasmon resonance bands. In this work, the fabrication of self-assembled PdxAg1-x NPs alloy nanostructures with distinct size, density, shape, and composition is demonstrated via the solid-state dewetting of sputtered Pd/Ag thin films on c-plane sapphire. The initial stage of bilayer dewetting exhibits the nucleation of voids, followed by the expansion of voids and cluster breakdown and finally shape transformation along with the temperature control. Bilayer composition shows a substantial influence on the dewetting such that the overall dewetting is enhanced along with the increased Ag composition, i.e. Pd0.25Ag0.75 > Pd0.5Ag0.5 > Pd0.75Ag0.25. On the other hand, the size and density of NPs can be efficiently controlled by varying the initial thickness of bilayers. Reflectance peaks in UV and near-infrared (NIR) regions and a wide absorption band in the visible region arisen from the surface plasmon resonance are observed in reflectance spectra. The peak intensity depends on the composition of PdxAg1-x NPs and the NIR peaks gradually blue-shift with the size decrement.
AB - Alloy nanoparticles (NPs) can offer a wide range of opportunities for various applications due to their composition and structure dependent properties such as multifunctionality, electronic heterogeneity, site-specific response, and multiple plasmon resonance bands. In this work, the fabrication of self-assembled PdxAg1-x NPs alloy nanostructures with distinct size, density, shape, and composition is demonstrated via the solid-state dewetting of sputtered Pd/Ag thin films on c-plane sapphire. The initial stage of bilayer dewetting exhibits the nucleation of voids, followed by the expansion of voids and cluster breakdown and finally shape transformation along with the temperature control. Bilayer composition shows a substantial influence on the dewetting such that the overall dewetting is enhanced along with the increased Ag composition, i.e. Pd0.25Ag0.75 > Pd0.5Ag0.5 > Pd0.75Ag0.25. On the other hand, the size and density of NPs can be efficiently controlled by varying the initial thickness of bilayers. Reflectance peaks in UV and near-infrared (NIR) regions and a wide absorption band in the visible region arisen from the surface plasmon resonance are observed in reflectance spectra. The peak intensity depends on the composition of PdxAg1-x NPs and the NIR peaks gradually blue-shift with the size decrement.
KW - alloy nanoparticles
KW - bilayer dewetting
KW - PdAg nanoparticles
KW - solid-state dewetting
KW - surface plasmon
UR - http://www.scopus.com/inward/record.url?scp=85042471417&partnerID=8YFLogxK
U2 - 10.1080/14686996.2018.1435944
DO - 10.1080/14686996.2018.1435944
M3 - Article
AN - SCOPUS:85042471417
SN - 1468-6996
VL - 19
SP - 160
EP - 173
JO - Science and Technology of Advanced Materials
JF - Science and Technology of Advanced Materials
IS - 1
ER -