A light-emitting element is a light-emitting element provided with a cathode electrode, an anode electrode, and a light-emitting layer formed between the cathode electrode and the anode electrode. The light-emitting layer is formed by a layer including blue quantum dot phosphor particles that emit blue light, green quantum dot phosphor particles that emit green light, and red quantum dot phosphor particles that emit red light.

A nanocrystal comprising a semiconductor material comprising one or more elements of Group IIIA of the Periodic Table of Elements and one or more elements of Group VA of the Periodic Table of Elements, wherein the nanocrystal is capable of emitting light having a photoluminescence quantum efficiency of at least about 30% upon excitation. Also disclosed is a nanocrystal including a core comprising a first semiconductor material comprising one or more elements of Group IIIA of the Periodic Table of Elements and one or more elements of Group VA of the Periodic Table of Elements, and a shell disposed over at least a portion of the core, the shell comprising a second semiconductor material, wherein the nanocrystal is capable of emitting light having a photoluminescence quantum efficiency of at least about 30% upon excitation. Also disclosed is a nanocrystal comprising a nanocrystal core and a shell comprising a semiconductor material disposed on at least a portion of the nanocrystal core, wherein the semiconductor material comprises at least three chemical elements and is obtainable by a process comprising adding a precursor for at least one of the chemical elements of the semiconductor material from a separate source to a nanocrystal core while simultaneously adding amounts of precursors for the other chemical elements of the semiconductor material. A population of nanocrystals, method for preparing nanocrystals, compositions, and devices including nanocrystals are also disclosed.