Molecularly Bridged Gold Nanoparticle Array for Sensing Applications

The fabrication of electronic devices using individual molecules necessitates an adept control of the placement of molecules and tuning the space between them. This paper provides an overview of sensing using molecularly bridged gold nanoparticles (AuNPs) with nanometer-sized space. We have attempted to form a nanometer-sized space in a two-dimensional network consisting of a repeated sequence of an AuNP-molecule-AuNP junction. It is possible to evaluate electron tunneling or electron transfer in an AuNP-molecule-AuNP junction by directly measuring the electrical resistivity of the two-dimensional network. The resistivity of the two-dimensional sequence, in turn, depends on the size and conducting states of the molecules in each junction. The molecular junction in such nanometer-sized structures can be moved and rearranged to any location, enabling the rapid development of miniaturized compact electronic devices.