Changes in the electronic properties of Bi2X3 (X: Se, Te) single crystals due to intercalation

Bi₂Se₃ and Bi₂Te₃ are layered semiconductors n-type and p-type, respectively, which belong to the family of thermoelectric materials. In this work we examine the insertion of Cu in Bi₂Te₃ and Bi₂Se₃ single crystals through an intercalation reaction. The inserted Cu acting as donor enhances the n-type character of Bi₂Se₃ while changing the native p-type character of Bi₂Te₃ to n-type. The spatial distribution of the intercalated species was monitoring by X-ray microanalysis and microscopic IR reflectivity measurements. Paper presented at the 4th Euroconference on Solid State Ionics, Renvyle, Galway, Ireland, Sept. 13–19, 1997