Advancing Ecofriendly Indium Phosphide Quantum Dots: Comprehensive Strategies toward Color-Pure Luminescence for Wide Color Gamut Displays

Indium phosphide (InP) quantum dots (QDs) are promising eco-friendly emitters for next-generation displays and optoelectronics, offering high efficiency, narrow spectral linewidths, and tunable luminescence. However, their commercialization faces challenges due to synthesis and fabrication difficulties, particularly slow progress in improving photoluminescence quantum yield (PLQY), full-width at half-maximum (FWHM), and external quantum efficiency (EQE). Despite persistent shared challenges such as stability and operational lifetime, the broader FWHM of InP QDs has increasingly emerged as a critical bottleneck for their commercialization, especially given recent breakthroughs, including near-unity PLQY in core-only/core–shell InP QDs and over 20% EQE in their electroluminescent applications. This review examines FWHM broadening mechanisms in InP QDs and outlines strategies to narrow FWHM through size, lattice, bandgap, surface, and device architecture engineering. It also highlights trends and future directions for high-performance InP QDs and their electroluminescent applications, aiming to advance their commercialization in heavy metal-free displays and optoelectronics.