Electrical conductivity of Au-nanoparticle-coated K2SO4 microcrystals deposited by DC trapping

Au-nanoparticle-coated K2SO4 microcrystals (nanoparticle-coated-crystals: NCCs) fabricated using the crystal-lattice-mediated-self-assembly method (CLAMS) were selectively deposited between gold electrodes by field-assisted trapping. Two different distances between electrodes were used, 2 μm and 118 nm. The electrical conductivity of NCCs was investigated using current-voltage (I-V) measurements at room and low temperatures and compared with that of bare tiopronin-coated Au nanoparticles. A hopping transport mechanism was found in both cases at low voltages and the corresponding activation energies were extracted. At higher voltages a power law was obtained in the case of NCCs and an exponential increase with voltage in the case of Au NPs