Quantum　dot　(QDs)　based　light-emitting　diode　devices　(QLEDs)　attracted　significant　academic　interest　due　to　their　outstanding　color　saturation　and　convenient　solution-based　manufacturing　processes.　At　present,　the　external　quantum　efficiency　(EQE)　of　cadmium-based　red,　green　and　blue　QLEDs　has　reached　the　theoretical　limit,　but　there　is　still　severe　carrier　injection　imbalance,　which　will　lead　to　a　significant　reduction　in　the　stability　and　lifetime　of　the　device.　In　this　work,　the　electron　transport　layer　(ETL)　is　doped　by　a　simple　method　to　reduce　the　electron　mobility　and　achieve　a　more　balanced　carrier　injection.　When　an　appropriate　amount　of　ethanolamine　(EA)　solution　is　added　to　the　ethanol　solution　of　ZnMgO,　the　amine　ion　(NH2−)　can　fill　the　oxygen　vacancy　in　ZnMgO,　thereby　regulating　the　electron　mobility　of　ZnMgO.　Compared　with　the　control　device,　the　EQE　of　the　optimized　device　increased　to　14.6%,　the　current　efficiency　(CE)　increased　to　60.7　cd/A,　increased　by　1.87　times　and　1.94　times　respectively,　and　the　peak　brightness　reached　252402　cd/m2　©　2025　Chinese　Vacuum　Society.　All　rights　reserved.