Solution-synthesis of Sb2Se3 nanorods using KSeCN as a molecular selenium source

Antimony selenide (Sb2Se3) is a low-toxic, element-abundant, narrow bandgap (Eg = ∼1.1–1.3 eV) semiconductor that shows potential for UV-Visible-Near-infrared optoelectronic applications. This paper reports the use of potassium selenocyanate (KSeCN) as a novel molecular selenium source to synthesize Sb2Se3 uniform nanorods. The resulting nanorods have been carefully characterized and are found to exhibit decent photoconductivity as well as broad-spectrum optical absorption with an Eg value of ∼1.35 eV. A molecular reaction mechanism is rationally proposed and evidenced for forming Sb2Se3, which is related to the thermal decomposition of selenocyanate (SeCN−) anions through the cleaving of Se–CN bonds to elemental Se(0), followed by its reduction to Se2− anions. Our work using KSeCN offers an alternative method for the synthesis of metal selenides with desirable nanostructures and properties.