AgI nanoparticles were prepared in large-scales by quenching the AgI melt in liquid nitrogen. XRD patterns showed that all of the nanocrystals were almost Y-AgI, and the size of the nanocrystals was about 9~15nm. UV-vis spectrum indicated that the band gap of the nanoparticle was 0.11eV less than that of bulk AgI. Alternating complex impedance analysis showed that the conductivity at room temperature of nanoparticles was 4.2×10−5Ω−1cm−1, and the responding conductivity activation energy was less than that of bulk AgI(0.25eV compared to 0.60eV). Furthermore, an anomalistic phenomenon was observed that the phase transition of common phase to superionic phase of AgI nanocrystals was a gradual process between 140°C and 235°C instead of a break at 146°C for bulk AgI.
