Narrow bandgap colloidal semiconductor nanocrystals have attracted increasing attention in recent years and studies have demonstrated their significant applications in optics,electronics,biomedicine,materials science,and other areas.Many studies have investigated colloidal Ag_2S quantum dots(QDs)due to their numerous advantages,such as near-infrared(NIR)emission,low toxicity,high quantum yields,high photo-colloidal stability,low cost,and facile synthesis.Compared with conventional NIR QDs(which contain heav...