Strategies for photoluminescence enhancement of AgInS2 quantum dots and their application as bioimaging probes

Synthesis and temporal evolution of Zn-doped AgInS2 quantum dots

“…The QY kept increase as the shell growth of ZnS in 15 min and reached maximum of 72%, but then dropped dramatically to 62% when the reaction time continued. Although the improvement of the QY was not as significant as many previous reports [8], the highest QY herein was up to ca.72%, which was considerable good as compared to those of the previously reported. It has been attributed that the surface of the QDs was well modified and it had a small amount of the non-radiative recombination at the surface sites.…”

Brightly luminescent colloidal Ag–In–S nanoparticles stabilized in aqueous solutions by branched polyethyleneimine

“…Such compounds combine a series of very attractive features, including relatively low toxicity and ability to preserve chalcopyrite structure in a broad range of NP sizes and non-stoichiometries [1,19,20,24,25]. So, by varying the chalcopyrite NP size, Cu(Ag):In:S ratio [1,20,21,[23][24][25][26][27] and introducing metal dopants (for example zinc(II) [1,20,23,27]) the position of PL maximum can be varied in a very broad range -from around 500 nm to the near IR range [1,[19][20][21]26]. The attractive luminescent properties stimulated greatly both studies of the feasibility of using ternary and quaternary metal chalcogenide NPs as luminescent bio-markers [1, 9-11, 13-15, 19-24, 26-30] and, at the same time, a search of the protocols allowing direct production and stabilization of luminescent ternary Cu-In-S [25,26,28,31,32] and Ag-In-S NPs [27,30] or quaternary Zn-Cu-In-S [25] and Zn-Ag-In-Se NPs [29] in aqueous solutions.…”

“…In particular, big expectations are associated with ternary indium-based chalcopyrites [1,19,20], such as CuInS 2 and CuInS 2 /ZnS NPs [13][14][15][16]20], non-stoichiometric Cu-In-S [20,21] and Ag-In-S NPs [10], CuInS x Se 2-x NPs [22], AgInS 2 and AgInS 2 /ZnS NPs [9,11,23,24] that can also be produced by the well-known "hot injection" methods with the PL QY reaching 40-65% [1,14,21,22]. Such compounds combine a series of very attractive features, including relatively low toxicity and ability to preserve chalcopyrite structure in a broad range of NP sizes and non-stoichiometries [1,19,20,24,25].…”

A new strategy for synthesizing AgInS2 quantum dots emitting brightly in near-infrared window for in vivo imaging

“…With a band gap of ~1.8 eV at room temperature, the AgInS 2 QDs can emit in the near-infrared region with high extinction coefficients, which offers an intriguing alternative for biological imaging applications 25 . So far, a variety of strategies have been established for the synthesis of AgInS 2 QDs [26][27][28][29] , most of which were carried out in organic phase and organic ligands were used as the capping agents for the QDs.…”