Selective Synthesis Of Ternary Copper Antimony Sulfde Nanocrystals And The Research Of Their Property

As an effcient way to obtain new materials, the alloying of metal chalcogenidenanocrystals (NCs) with different chemical compositions and crystalline structures hasattracted intense attention recently, due to their signifcance in fundamental studies andpractical applications.Ternary copper antimony sulfde nanocrystals (CAS NCs) have attracted increasing attention in photovoltaics and photoelectric nanodevices due to their tunable band gaps in the near-IR regime. Although much progress in the synthesis of CAS NCs has been achieved, the selective synthesis of CAS NCs with controllable morphologies and compositions is preliminary: in particular, a facile method is still in demand. In this work, we have successfully selectively synthesized high-quality CAS NCs with diverse morphologies, compositions, and band gaps, including rectangular CuSbS2nanosheets (NSs), trigonal-pyramidal Cu12Sb4S13NCs, and rhombic Cu3SbS3NSs, by cothermodecom-position of copper diethyldithiocarbamate trihydrate (Cu(Ddtc)2) and antimony diethyldithiocarbamate trihydrate (Sb(Ddtc)3). The direct and indirect band gaps of the obtained CAS NCs were systematically studied by performing Kubelka Munk transformations of their solid-state diffuse refectance spectra. Direct bands are all in good agreement with the previous reports of bulk CAS NCs. Thiswork has also frst presented the indirect band gaps of the three CAS NCs, in good complement to the literature. Furthermore, we expect that such a facile syntheticmethod could be extended to the synthesis of other multinary metal sulfde NCs with desirable band gaps and optical properties.