Enhanced photothermal behavior derived from controllable self-assembly of Cu1.94S microstructures

Abstract

New ordered architectures or morphologies could be obtained through the self-assembly process and usually generate new physical and chemical properties. Here we report an adjustable self-assembly research study on copper sulphide nanocrystals (Cu_1.94S NCs) forming five kinds of plant-like morphologies. Hydrophobic Cu_1.94S quantum dots were prepared in the CHCl₃ phase and transferred to the aqueous phase and capped with cysteine or penicillamine through a ligand exchange technique. Afterwards, a facile and eco-friendly self-assembly process (without using any template or surfactant) was employed. Through regulating the conditions including the solvent composition, surface ligand and starting concentration of Cu_1.94S NCs, five delicate architectures were obtained. In addition, the possible formation process and growth mechanism of the obtained three-dimensional (3D) Cu_1.94S architectures was also proposed and discussed. The assembled Cu_1.94S architectures show improved molar extinction coefficients compared with individual Cu_1.94S NCs, and in this way, better photothermal performance is achieved.