DNA Assisted Assembly of Multisegmented Nanowires

This work demonstrates a highly specific and selective assembly of multisegmented nanowires on prepatterned gold electrodes using DNA hybridization. Multisegmented Au/Pd/Au nanowires were synthesized using template‐directed electrodeposition. Two complementary single‐stranded DNAs modified with thiol tags adsorb on gold electrodes and gold segments of nanowires, and enable the nanowires to assemble across electrodes. The assembled nanowires show ohmic contact with minimum contact resistance. Using these nanowires, the temperature dependent electrical resistance and the sensing performance toward hydrogen were investigated. The temperature coefficient of resistance of nanowires was lower than bulk polycrystalline counterpart, because of higher electron scattering at the surface and grain boundaries of nanowires. The nanowires were sensitive toward hydrogen gas at room temperature with a detection limit of 0.5%.