Silver Amalgam Nanoparticles and Microparticles: A Novel Plasmonic Platform for Spectroelectrochemistry

Abstract

Plasmonic nanoparticles from unconventional materials can improve or even bring some novel functionalities into the disciplines inherently related to plasmonics such as photochemistry or (spectro)electrochemistry. They can, for example, catalyze various chemical reactions or act as nanoelectrodes and optical transducers in various applications. Silver amalgam is the perfect example of such an unconventional plasmonic material, albeit it is well-known in the field of electrochemistry for its wide cathodic potential window and strong adsorption affinity of biomolecules to its surface. In this study, we investigate in detail the optical properties of nanoparticles and microparticles made from silver amalgam and correlate their plasmonic resonances with their morphology. We use optical spectroscopy techniques on the ensemble level and electron energy loss spectroscopy on the single-particle level to demonstrate the extremely wide spectral range covered by the silver amalgam localized plasmonic resonances, ranging from ultraviolet all the way to the mid-infrared wavelengths. Our results establish silver amalgam as a suitable material for introduction of plasmonic functionalities into photochemical and spectroelectrochemical systems, where the plasmonic enhancement of electromagnetic fields and light emission processes could synergistically meet with the superior electrochemical characteristics of mercury. Supporting Information: Size distribution statistics; mercury weight percentage in the AgA MPs; FDTD numerical simulations; TEM images and EEL maps of additional AgA NPs; EDX maps of AgA NPs with Ag satellites; numerical simulations of a AgA nanodisc in vacuum and EELS and BEM analysis of a AgA nanorod.

Electrodeposition of Silver Amalgam on Thin Gold Film Electrodes for Voltammetric Detection of 4‐Nitrophenol and DNA Labeled with Osmium Tetroxide‐Bipyridine Complex

“…Moreover, increasing the density and decreasing the size of the AgAPs conforms with the requirements for its potential application in optical and spectro-electrochemical systems (e.g. dark-field spectroscopy shows AgAPs' surface plasmon resonances of on ITO in a visible range of wavelengths for a particle size below 200 nm) [33]. According to these requirements and to the highest and the most well-developed CV signals of 4-NP, the deposition solution containing 30.6 w% Ag was selected for further optimizing the DPCA parameters in the following Chapter 3.3.…”

Mechanistic Investigations into and Control of Anisotropic Metal–Organic Framework Growth

“…Controlled growth of nanoparticles and microparticles has been of interest in several research fields due to their applications in polymer composites, 1−7 medicine, 8−11 catalysis, 12,13 water purification, 14−16 and energy. 17,18 Particle size critically affects the functionality of these applied materials, including composite reinforcement, 19−22 drug delivery efficacy and toxicity, 23−25 catalytic activities, 12,26−29 reverse osmosis membrane performance, 30 and chromophore optical properties.…”

“…Controlled growth of nanoparticles and microparticles has been of interest in several research fields due to their applications in polymer composites, − medicine, − catalysis, , water purification, − and energy. , Particle size critically affects the functionality of these applied materials, including composite reinforcement, − drug delivery efficacy and toxicity, − catalytic activities, ,− reverse osmosis membrane performance, and chromophore optical properties. − Recently, a class of crystalline and porous coordination polymers, metal–organic frameworks (MOFs), have received considerable attention for nanoscale and microscale applications. − These versatile materials, composed of organic multidentate ligands and metal nodes, exhibit tunable topology, crystal size, and surface and pore chemistry, putting MOFs on the frontier of applied materials research. − Depending on framework connectivity and composition, MOFs can show either isotropic or anisotropic growth . Understanding the underlying mechanisms of each type of growth is essential in order to not only selectively tune the MOF particle size and aspect ratio but also to obtain monodisperse crystals.…”

Electrodeposition of Silver Amalgam Particles on Screen-Printed Silver Electrodes in Voltammetric Detection of 4-Nitrophenol and Artificial Nucleosides dTPT3 and d5SICS

“…Electrodeposition of silver amalgam particles (AgAPs) on various substrates was found to be perspective approach for development of novel (spectro-)electroanalytical systems applicable in detection of electrochemically reducible compounds, nucleic acids or proteins [1][2][3][4] . Moreover, AgAPs were confirmed as a suitable material for introduction of plasmonic functionalities into photochemical and spectro-electrochemical systems [5] . Until recently, electrochemical studies, following AgAPs deposition on selected substrates from a deposition solution of Ag + and Hg 2+ , required additional reference and counter electrodes.…”