Structural Engineering of Vacancy Defected Bismuth Tellurides for Thermo-electric Applications K. Termentzidis, A. Pokropivny, S.-Y. Xiong, Y. Chumakov, P. Cortona and S. Volz EPJ Web of Conferences, 33 (2012) 02012 Published online: 02 October 2012 DOI: 10.1051/epjconf/20123302012