Abstracts <p>ZnCuInS/ZnSe/ZnS quantum dots (QDs) are a non-toxic and environmentally benign semiconductor material. Specifically, their tunable emission, high photoluminescence quantum yield (PLQY), and good stability make them promising candidates for applications such as light-emitting diodes (LEDs) and bioimaging. However, the expensive price of the rare metal element indium increases its preparation cost, thereby hindering the wider application of ZnCuInS-based QDs. Therefore, we propose to partially replace In with low-cost Al to produce ZnCuAlInS/ZnSe/ZnS core/shell/shell QDs, which reduces the cost to some extent. As a result, compared with ZnCuInS/ZnSe/ZnS QDs (ZCIS QDs) the ZnCuAlInS/ZnSe/ZnS QDs (ZCAIS QDs) exhibited a blue shifted photoluminescence (PL) spectrum, a narrower full width at half maximum (FWHM), and an approximately 95% increase in PLQY. The enhanced performance positions them as promising materials for optoelectronic applications. Furthermore, we fabricated white light-emitting diodes (WLEDs) composed of blue InGaN LED chips and ZCAIS QDs. The resulting White LED exhibited a warm-white emission with CIE 1931 chromaticity coordinates of (0.3284, 0.3277), a correlated color temperature (CCT) of 5690 K, and a luminance of 23130 cd/m². This work provides a cost-effective, environmentally benign strategy for WLED production while establishing a foundation for future optimization of QD-based optoelectronic devices. Critically, the ZCAIS QDs exhibit strong potential as a substitute for conventional toxic (e.g., Cd/Pb-based) or expensive (e.g., InP-based) phosphors in solid-state lighting.</p>