Ag2S Nanoparticles Evolved into Luminescent AgInS2?In2S3 Heteronanoparticles through Dual Formation Mechanism

作者：Zhang, Yongliang^*; Chang, Cheng; Liu, Peifeng; Lei, Junyu; Cai, Jing^*

来源：PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, 2022, 39(7): 2200054.

DOI：10.1002/ppsc.202200054

• Ag2-3 delta In delta S
• AgInS2
• In2S3
• band-edge emissions
• dual formation mechanisms

A deep understanding of the growth kinetics and mechanism of metal sulfide nanostructure is helpful in preparing nanomaterials with controllable structures. This study reports a facile synthetic protocol for the luminescent AgInS2@In2S3 core@shell heteronanoparticles through the reaction of preformed Ag2S nanoparticles with excess [(C4H9)(2)NCS2](3) In in dodecanethiol. A dual formation mechanism for the orthorhombic AgInS2(o-AgInS2) component is proposed, that is, the cation exchange of partial Ag+ in Ag2S nano- particle by to produce the metastable AglnS(2) and alloying of the In2S3 formed through direct decomposition of [(C4H9)(2)NCS2](3) In with Ag2S nanoparticles to produce AgInS2. Following the dual formation mechanism, the Ag2S nanoparticle first evolves into the intermediate Ag(2-3 delta)ln(delta)S/o-AglnS(2) Janus heteronanoparticle without band-edge emission of o-AglnS(2), then converts to the o-AglnS(2) nanoparticle, and finally transforms to the o-AglnS(2)@ln(2)S(3) core@shell heteronanoparticle with band-edge emission of o-AgInS2. The appearance of band-edge emission might be attributed to the removal of the surface defects of the o-Agln S-2 core by coating the In2S3 shell. This study would provide a facile protocol for the synthesis of IR-MA-VIA 2 nanomaterials with controlled architecture and benefit the development of monochromatic luminescent apparatus.