Bismuth antimonides, Bismuth-antimonys, or Bismuth-antimony alloys, (BiSb) are binary alloys of bismuth and antimony in various ratios.
Some, in particular BiSb, were the first experimentally-observed three-dimensional topological insulators, materials that have conducting surface states but have an insulating interior.
Various BiSb alloys also superconduct at low temperatures, are semiconductors, and are used in thermoelectric devices.
Bismuth antimonide itself (see box to right) is sometimes described as BiSb.