Metal-Alkylamine Complex Mediated Uni-Micelle Towards Size-Controlled Synthesis of Monodisperse Silver Sulfide Quantum Dots

Silver sulfide quantum dots have attracted large attentions due to their large potential applications in dealing with global energy crisis and environmental pollution. However, the synthesis for monodisperse nanocrystals of several nanometers have puzzled scientists for two decades. Here we report an alkylamine manipulating uni-micelle protocol for controlled synthesis of Ag2S quantum dots, which includes a reversible phase-transfer procedure enabling silver ions to be dual-soluble, and a uni-micelle process employing silver-oleylamine complex as oil-soluble precursor, in which there is only one kind micelle containing aqueous solution of Na2S while the dual soluble Ag(I) precursor is added into oil phase. Monodisperse Ag2S quantum dots were directly synthesized with a controlled size of 4.2nm/5.6nm/7.5nm and narrow distribution () of ~3.3. The as-synthesized Ag2S QDs could be well organized into hexagonal close-packed supra-crystalline lattice and showed tunable dispersity in W/O employing different ligands. The findings suggest the protocol can offer a versatile platform for synthesizing numbers of metal sulfide quantum dots with rational designed size for high photocatalytic performance.