Review—Electrolytic Metal Atoms Enabled Manufacturing of Nanostructured Sensor Electrodes

Abstract

Sensing materials play a key role in the successful implementation of electrochemical sensors, and nanotechnology has emerged as an important and rapidly growing field for stimulating the innovation of high-performance sensors. The fabrication, characterization, and evaluation of the nanostructured electrodes are therefore a focus of this field. Compared to a variety of dry and wet technologies which have been extensively developed for this purpose, electrochemical methods are typically convenient, highly effective, and potentially low-cost for the production of different nanostructures. This minireview is designed to introduce a unique electrochemical method - electrolytic metal-atom enabled manufacturing (EM2) and its application in electrochemical sensors. The EM2 technique employs electrolytic metal atoms generated from their corresponding salt precursor as a tool to nanostructure a wide range of substrate electrodes used in electrochemical sensors, based on a one-pot electrochemical deposition and dissolution of the metal atoms in the same electrolyte bath. Briefly, the metal atoms are electrodeposited on a substrate electrode during the cathode reduction, and they are selectively removed from the substrate during the subsequent anode oxidation. Because of the interactions between the electrolytic metal atoms and the substrate atoms, the repetitive electrodeposition and dissolution of the former on the substrate enable the nanostructuration of the substrate, particularly within its surface layers. The nanostructured electrodes have demonstrated very attractive performance for the determination of numerous analytes, such as high sensitivity and selectivity, high interference tolerance, and low detection limits. However, the EM2 technique and the application of the resulting nanostructured electrodes in electrochemical sensors and beyond have still been very limitedly investigated. In order to bring the community from academic, industries, agencies, and customers together to develop the EM2 technique and advance electrochemical sensor systems, this minireview will introduce the thermodynamic and kinetic fundamentals of this technique, the characterization of resulting nanostructures, the analysis of their electrochemical behavior, and the implementation of this technique for the development of advanced sensor electrodes. Finally, an outlook with a focus on further research areas is provided.

Electrochemical fabrication of mesoporous metal-alloy films

“…The cutting-edge nanotechnology is capable of developing porous structures with pore sizes ranging from 2 nm to 100 nm and spacing widths ranging from 50 to 100 nm with desired geometry. 44 The most used strategies adapted for fabricating such alloys include template-based strategies (soft and hard template), potential-controlled surfactant assembly, colloidal assembly, interfacial surfactant templating, deposition from lyotropic liquid crystalline phases of surfactants, sol–gel assembly, electro-assisted self-assembly method, etc. Each strategy is specific and provides films with defined shape, quality, elemental composition, architecture, and pore definition.…”

DC Sputtered Ultralow Loading Gold Nanofilm Electrodes for Detection of As (III) in Water

“…Our study is aligned with recent efforts to develop facile and low-cost electrode fabrication methods beyond screen printing and Au wire electrodes, which could increase access to electrochemical detection. [38][39][40][41][42] Therefore, this study seeks to investigate the suitability of electrodes prepared by DC sputtered to be used as an alternative to nanoparticle, screen printing, and wire electrodes. This is the first investigation presenting the use of ultralow (<10 μg cm −2 ) gold loading on carbon, formed using sputter z E-mail: garzon@unm.edu deposition, to detect As (III) in water.…”

Superatom Generation and Deposition of Alkali-like Ta@Si16 and Halogen-like Al13 via Atomic Aggregation

“…Surface modifications via electrochemical processes, including electroless plating, have attracted attention from the viewpoint of surface modification for nanostructured functionalization relevant to nucleation and growth phenomena during electrodeposition and dissolution. [1][2][3][4] However, it is difficult to form a uniform nanostructure with electrochemical surface modification because of the accompanying distributions of various local surface structures. A cause of the non-uniformity is the atom diffusion on the surface, forming diverse-sized atomic aggregates.…”