Hall effect of /spl alpha/- and /spl beta/-Zn/sub 4/Sb/sub 3/ compounds prepared by the gradient freeze and spark-plasma sintering methods

The Hall effect has been measured on the /spl alpha/- and /spl beta/-phase of Zn/sub 4/Sb/sub 3/ bulk samples prepared by the gradient freeze and spark-plasma sintering methods in the temperature range from 78 to 300 K. The thermal variation of the carrier concentration and hole mobility has been discussed for these two samples. The thermoelectric and transport properties have also been compared with those of the samples synthesized by different methods.