ESI. Mat. Lett. Bi2Se3 NPs

Nanoparticles of Bi2Se3 were prepared by hot injection method using bismuth nitrate and 1,3-dimethyl-1H-benzo[d]imidazole-2(3H)-selenone (a cyclic selenourea) synthesized in the laboratory as selenide source. This cyclic selenourea was produced with a yield of 67% by reacting elemental selenium powder with 1,3-dimethyl-1H-benzo[d]imidazol-3-ium iodide made from laboratory reagents. Different solvents: triethanolamine, oleylamine, and oleic acid used in the hot-injection processing affected the shape, composition, and crystallinity of the resulting Bi2Se3 nanoparticles. X-ray diffraction patterns confirm the rhombohedral crystalline structure of the material with an average crystallite size of 13 - 19 nm. FESEM reveals that the material was obtained as nanosheet. Optical diffuse reflectance spectrum of the material suggests an indirect bandgap of 0.78 eV for it

本研究采用热注入法，以硝酸铋为铋源，以实验室合成的1,3-二甲基-1H-苯并[d]咪唑-2(3H)-硒酮（一种环状硒脲）作为硒源，制备了硒化铋(Bi₂Se₃)纳米颗粒。该环状硒脲由单质硒粉与实验室试剂制备的1,3-二甲基-1H-苯并[d]咪唑鎓碘化物反应制得，产率为67%。热注入工艺中使用的三乙醇胺、油胺、油酸三种不同溶剂，会对所得硒化铋纳米颗粒的形貌、组分与结晶度产生影响。X射线衍射(X-ray diffraction, XRD)图谱证实该材料具有菱面体晶型结构，平均晶粒尺寸介于13~19 nm之间。场发射扫描电子显微镜(Field Emission Scanning Electron Microscopy, FESEM)观测显示，产物呈现纳米片形貌。该材料的光学漫反射光谱表明其具有0.78 eV的间接带隙。