Highly luminescent semiconductor nanocrystals

Abstract

A semiconductor nanocrystal can have a photoluminescent quantum yield of at least 90%, at least 95%, or at least 98%. The nanocrystal can be made by sequentially contacting a nanocrystal core with an M-containing compound and an X donor, where at least one of the M-containing compound and the X donor is substoichiometric with respect to forming a monolayer on the nanocrystal core.

1 . A semiconductor nanocrystal having a photoluminescent quantum yield of at least 90%. 
     
     
         2 . The semiconductor nanocrystal of  claim 1 , wherein the semiconductor nanocrystal comprises a core including a first semiconductor material and a shell including a second semiconductor material. 
     
     
         3 . The semiconductor nanocrystal of  claim 2 , wherein the first semiconductor material is ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe, InN, InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, PbTe, or a mixture thereof. 
     
     
         4 . The semiconductor nanocrystal of  claim 3 , wherein the second semiconductor material is ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe, InN, InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, PbTe, or a mixture thereof. 
     
     
         5 . The semiconductor nanocrystal of  claim 1 , wherein the semiconductor nanocrystal is a member of a population of semiconductor nanocrystals, wherein the population exhibits photoluminescence with a full width at half max (FWHM) of less than 30 nm. 
     
     
         6 . The semiconductor nanocrystal of  claim 2 , wherein the first semiconductor material is CdSe. 
     
     
         7 . The semiconductor nanocrystal of  claim 6 , wherein the second semiconductor material is CdS. 
     
     
         8 . (canceled) 
     
     
         9 . The method of  claim 8 , further comprising repeating the step of sequentially contacting the nanocrystal core with an M-containing compound and an X donor. 
     
     
         10 . The method of  claim 8 , wherein both the M-containing compound and the X donor are substoichiometric with respect to forming a monolayer on the nanocrystal core. 
     
     
         11 - 17 . (canceled) 
     
     
         18 . A population of semiconductor nanocrystals, wherein the population exhibits photoluminescence with a quantum yield of at least 90% and a full width at half max (FWHM) of less than 30 nm. 
     
     
         19 . The population of  claim 18 , wherein the wherein the population exhibits photoluminescence with a quantum yield of at least 95%. 
     
     
         20 . The population of  claim 18 , wherein the wherein the population exhibits photoluminescence with a quantum yield of at least 98%.