“…[51] Meanwhile, several groups have also performed low temperature syntheses of (Bi x Sb 1À x ) 2 Te 3 nanoparticles using wetchemical based approaches, however very few have reported on the consolidation of the resulting materials for transport measurements. [48,[52][53][54] Notably, Liu and co-workers hydrothermally synthesized Bi 0.5 Sb 1.5 Te 3 nanocrystals by reaction of ECl 3 (E = Sb, Bi) with elemental Te in the presence of NaBH 4 as reducing agent; the nanocrystal powders were then consolidated by cold-pressing and sintering, whereas Dharmaiah and co-workers applied spark plasma sintering instead. [55,56] Unfortunately, the reductive conditions and low thermal stability of traditional precursors [i. e. BiCl 3 , Bi(AOC) 3 , Bi(NMe 2 ) 3 ] that are typically used in solution-based methods often lead to Te-or Birich materials due to the incorporation of unwanted metal impurities into the crystal lattice.…”