Objective　Inorganic　perovskite　quantum　dots　(PQDs)　have　garnered　significant　interest　due　to　their　exceptional　optical　characteristics,　including　narrow　emission　spectra　and　high　photoluminescence　quantum　yield　(PLQY).　Despite　these　advantages,　PQDs　are　often　hindered　by　environmental　instability,　particularly　notable　in　CsPbI3　QDs　which　exhibit　lower　PLQY　and　susceptibility　to　phase　transitions　at　ambient　conditions,　compromising　optical　performance.　To　address　these　challenges,　enhancing　the　stability　and　optical　properties　of　CsPbI3　QDs　is　crucial.　Current　research　focuses　on　methods　such　as　ligand　exchange,　encapsulation,　and　ion　doping,　with　the　latter　proving　particularly　effective　in　improving　PLQY　and　stability.　Ion　doping,　involving　substitution　at　A,　B,　or　X　sites,　can　mitigate　Pb　toxicity,　alter　bond　lengths,　and　enhance　phase　stability,　thereby　significantly　impacting　quantum　dot　performance.　Initial　CsPbI3　QDs　typically　demonstrate　a　PLQY　of　50%　to　60%　but　suffer　rapid　fluorescence　quenching　within　ten　days　in　environmental　settings.　This　study　proposes　Zn　ion　doping　as　a　promising　strategy　to　augment　the　optical　properties　of　perovskite　quantum　dots.　Methods　This　article　employs　a　high-temperature　thermal　injection　method　for　the　synthesis　of　Cs-oleate　precursors.　Initially,　Cs-oleate　precursors　are　synthesized　and　subsequently　rapidly　injected　into　a　high-temperature　octadecene　solution　containing　PbX2,　ZnI2　and　ligands.　The　reaction　proceeds　for　a　few　seconds　before　the　mixture　is　quenched　in　an　ice　water　bath.　Various　molar　ratios　of　ZnI2/PbI2　can　be　adjusted　to　achieve　a　series　of　CsPb1-xZnxI3　(0　2　concentration,　while　the　overall　cubic　structure　of　the　QDs　remains　unchanged.　This　modification　enhances　the　radiative　recombination　rate　and　effectively　mitigates　defect　states.　The　maximum　enhancement　in　photoluminescence　quantum　yield　(PLQY)　reaches　98%,　accompanied　by　improved　stability(Fig.3(b)).　Original　CsPbI3　QDs　exhibit　complete　fluorescence　quenching　within　ten　days　at　room　temperature,　whereas　Zn-doped　CsPbI3　QDs　maintain　over　80%　of　their　initial　PLQY　under　the　same　conditions(Fig.3(d)).　Transmission　electron　microscopy　(TEM)　analysis　shows　that　despite　the　addition　of　ZnI2　precursor,　the　QDs　retain　their　cubic　morphology,　with　the　average　particle　size　decreasing　from　18.9　nm　to　17.6　nm.　This　size　reduction　is　attributed　to　the　inhibitory　effect　of　I　ions　on　further　QD　growth.　The　interplanar　spacing　of　the　QDs　decreases　from　3.16　Å　to　3.13　Å,　indicating　lattice　contraction　induced　by　Zn　doping.　X-ray　diffraction　(XRD)　patterns　confirm　that　Zn-doped　CsPbI3　QDs　exhibit　no　new　diffraction　peaks　compared　to　pure　CsPbI3　QDs,　but　show　a　gradual　shift　of　peaks　towards　larger　angles,　indicating　successful　substitution　of　Pb　by　Zn　ions.　Analysis　of　time-resolved　photoluminescence　(TRPL)　spectroscopy　reveals　that　CsPbI3　QDs　have　an　average　fluorescence　lifetime　of　138.44　ns,　while　Zn-doped　CsPbI3　QDs　exhibit　a　shorter　lifetime　of　103.61　ns(Fig.3(e)),　attributed　to　the　suppression　of　halogen　vacancy　defects　and　shallow-level　states　by　Zn　doping(Tab.1).　This　doping　strategy　effectively　passivates　surface　defects　and　enhances　the　optical　properties　of　CsPbI3　QDs.　Conclusions　In　this　study,　CsPbI3　quantum　dots　doped　with　Zn2+　were　successfully　synthesized　using　ZnI2　via　the　thermal　injection　method.　The　incorporation　of　Zn　enhanced　the　phase　stability　of　CsPbI3　quantum　dots　compared　to　their　undoped　counterparts.　Photoluminescence　quantum　yield　(PLQY)　significantly　improved　from　56%　to　98%,　with　PLQY　retention　above　80%　after　10　days.　Subsequently,　narrow-emitting　Zn:CsPbI3,　CsPbBr3,　and　CsPbCl3　quantum　dots　were　selected　as　replacements　for　conventional　phosphors　in　LED　color　conversion　materials.　These　quantum　dots　achieved　a　color　gamut　of　135.22%　based　on　the　National　Television　Standards　Committee　(NTSC)　standard(Tab.2),　highlighting　their　promising　applications　in　LED　display　technologies.　Copyright　©2025　Infrared　and　Laser　Engineering.　All　rights　reserved.