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ZnS nanoparticles doped with Cu(I ) by controlling coordination and precipitation in aqueous solution A novel method for the synthesis of ZnS5Cu colloids has were used as both ligand and surfactant, and acted to stabilize been studied in aqueous solution, in which the Cu+ ions Cu+ ions in aqueous solution and minimize the solubility were incorporated into the ZnS matrix by the assistance diVerence between Cu2S and ZnS. By the use of these sulfur of a sulfur-containing ligand, i.e. thiourea or thiosulfate. containing ligands, nanosized ZnS5Cu particles were obtained The optical properties of the colloids (absorption, emission and their optical properties (absorption, excitation, and emisand excitation spectra) were studied. Compared with the sion spectra) were studied. bulk materials, the absorption band-edge is blue-shifted, ZnS colloid was prepared as described previously,5,6 with which is attributed to a quantum size effect. The average only minor modifications. Freshly prepared ZnCl2 and ligand ZnS nanoparticle size, deduced from the absorption spec- solutions (thiourea or sodium thiosulfate) were stoichiotra by an effective mass approximation, is about 4 nm. metrically mixed together. Under continuous stirring, freshly Upon excitation at 325 nm, a broad green emission band prepared sodium sulfide solution was added to the above is observed, while for samples doped with 0.2% Cu, a blue mixture. The addition rate was controlled at 1.0 ml min−1 by emission band at 450 nm is also observed, which is quenched at higher dopant concentrations.本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。