“…Recently, doping of Cd, In, Al, Hg, Mg, Nb, Cu, Te and Se [10,[14][15][16][17][18][19][20][21][22][23][24] in Zn 4 Sb 3 have been reported. These studies showed that when doping with Cd, In or Mg, the thermoelectric performance of Zn 4 Sb 3 was not improved obviously.…”