“…Compounds composed of Cu−Bi−S have been reported with various phases according to their compositions, such as Cu 9 BiS 6 , Cu 3 BiS 3 ,22 CuBiS 2 , Cu 4 Bi 4 S 9 ,, and a theoretical phase of Cu 4 Bi 5 S 10 . Although some of phases of high Bi ratio Cu−Bi−S have been reported previously, such as CuBi 5 S 8 and its derivatives,, however the synthetic method for these compounds needs a tedious vacuum‐sealed high temperature melted flux process. Generally, ternary Cu−Bi−S sulfides could be synthesized with reactive sintering method, solvothermal method, polyol route, chemical bath deposition method,, vacuum‐sealed solid state reaction, and colloidal hot‐injection method ,.…”