Rapid synthesis and characterization of magnesium oxide nanocubes via DC arc discharge

Direct current (DC) arc discharge method gives high temperature in a short time, which has been widely used to prepare carbon nanotubes. We use this simple approach to synthesize magnesium oxide (MgO) nanocubes without any catalyst. Structural characterizations indicate that the as-synthesized MgO nanocubes are all single crystalline, and enclosed by {100} facets. The edge lengths mainly range from 60 nm to 100 nm. Most nanocubes interlace with adjacent nanocubes as three types: point contacts, line contacts and face contacts. The blue band in PL spectrum is ascribed to various structural defects, the nanosize effect and surface states of MgO nanocubes.