Semiconductor nanoparticles and method of producing semiconductor nanoparticles

A method of producing semiconductor nanoparticles, comprising:

• providing a dispersion by dispersing primary semiconductor nanoparticles into a solvent, each of the primary semiconductor nanoparticles comprising a semiconductor that contains M1, M2, and Z, wherein M1 is at least one element selected from the group consisting of Ag, Cu, and Au, and comprises at least Ag, M2 is at least one element selected from the group consisting of Al, Ga, In, and Tl, and comprises at least In, and Z is at least one element selected from the group consisting of S, Se, and Te, and comprises at least S;
• and
• adding, to the dispersion, a compound containing a Group 13 element, and an elemental substance of a Group 16 element or a compound containing the Group 16 element to form a semiconductor layer comprising the Group 13 element and the Group 16 element on a surface of each of the primary semiconductor nanoparticles,
• wherein the Group 13 element comprises at least Ga and the Group 16 element comprises at least S,
• wherein the semiconductor layer has an amorphous structure, and
• wherein a photoluminescence lifetime of the semiconductor nanoparticles is 200 ns or less.