Full Color Al-Doped InP Quantum Dots with High Brightness via Gram-Scale One-Pot Synthesis for White Light-Emitting Diodes

High-performance, environmentally friendly indium phosphide (InP)-based quantum dots (QDs) are urgently needed to meet the demands of rapidly evolving display and lighting technologies. By adopting the highly efficient and cost-effective one-pot method and utilizing aluminum isopropoxide (AIP) as the Al source, a series of Al-doped InP/(Al)ZnS QDs with emission maxima ranging from 480 to 627 nm were synthesized. The photoluminescence quantum yield (PLQY) of the blue, green, yellow, orange, and red QDs, with emission peaks at 480, 509, 560, 600, and 627 nm, reached 34%, 62%, 86%, 96%, and 85%, respectively. Remarkably, the required reaction times for synthesizing the above QDs were all within 4 h, showcasing the high efficiency of this one-pot method. Moreover, the influence of Al-doping on red InP/ZnS QDs was thoroughly explored. Compared with undoped QDs, the increased PLQY, narrowed full-width at half-maximum (fwhm), and enhanced photostability were observed in Al-doped QDs. Characterization results revealed the relatively thicker shell in Al-doped QDs and demonstrated the presence of Al in the shell in the form of AlPO_x. The increased shell thickness and narrowed fwhm indicated a reduced lattice strain at the core-shell interface in Al-doped QDs, which might result from the introduced trivalent Al³⁺, as it alleviated the charge mismatch at the core/shell interface. Approximately 3 g of QDs powders can be obtained through a single gram-scale one-pot preparation. The on-chip white light-emitting diode (LED), using the red and green Al-doped QDs as phosphors, exhibited a maximum power efficiency of 17.8 lm W^-1 and stable CIE coordinates around (0.32, 0.35), and achieved a wide color gamut (97.4% of the NTSC color space), demonstrating the promising potential in lighting technologies.