Conductance-Based Chemical Sensing in Metallic Nanowires and Metal-Semiconductor Nanostructures

Abstract

Conductance-based chemical sensing in metal-semiconductor nanostructures and all-metal nanowires of atomic dimensions is garnering increased interest. Adsorbed gas molecules can migrate to a metal-semiconductor junction, thereby shifting the magnitude of the Schottky barrier and altering electrical impedance, whereas atomic scale metal junctions can sensitively report the presence of adsorbates through their impact on ballistic electron transport.

On “resistance overpotential” caused by a potential drop along the ultrathin high aspect ratio gold nanowire electrodes in cyclic voltammetry

“…Size-dependent intrinsic properties of nanomaterials are advantageous for some applications, e.g., chemiresistive sensing [4,[20][21][22][23][24][25][26][27]. However, these properties cause crucial deviations in the NWs behavior as electrodes from that of classical metal electrodes.…”

Molecularly Bridged Gold Nanoparticle Array for Sensing Applications

“…1 nanometer-sized electronics. [2][3][4][5][6][7][8][9][10][11][12][13][14] They also act as important tools in the characterizing the properties of molecules and materials at the nanometer scale. In the past decade, researchers have reported several techniques for the fabrication of nanogap electrodes, and demonstrated their potential applications in the analysis of molecules and nanomaterials.…”

“…[24][25][26][27] In particular, the combination of top-down and bottom-up approaches has been a successful strategy for providing the desired configuration, placement of molecules into the nanospace, and realizing promising molecular recognition results. [12][13][14][28][29][30][31][32][33][34] In principle, bottom-up fabrication is achieved through the binding, interaction, self-assembly, and self-organization characteristics of molecules and materials as building blocks. [35][36][37][38][39] Precise control of the spacing between the fabricated electrodes for specific molecules is expected to allow ultrasensitive sensing.…”

Placement of Nanospace on an Electrode for Biosensing

“…[64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81] They are also important tools for characterizing the properties of molecules and materials at the nanometer scale. During the past decade, many techniques for fabrication and potential applications of nanogap electrodes for the analysis of molecules and materials beyond the capability of traditional microfabrication technologies have been reported.…”

“…In particular, the combination of top-down and bottom-up approaches has provided a desired configuration, placement of molecules into nanospace, and promising molecular-recognition results. 76,77,[79][80][81][82][83][84][85][86][87][88] Bottom-up fabrication is achieved through the binding, interaction, self-assembly, and self-organization characteristics of molecules and materials as building blocks. 89 Nanogap devices provide a sufficient level of sensitivity, to as few as a single or small number of biomolecules, with direct transduction of biomolecule-specific binding events into electrical signals.…”