InGaP Alloyed Quantum Dots Enabled by Rational Indium Precursor Design for Light-Emitting Diodes

Indium gallium phosphide (InGaP) alloyed quantum dots (QDs) are considered promising alternatives to indium phosphide (InP) QDs owing to their wider bandgap and potential for broad visible-light absorption. The conventional synthesis often results in an undesired InP/GaP core–shell structure rather than InGaP alloys without careful precursor design due to the higher reactivity of indium compared to gallium. Here, we introduce a tailored indium precursor, indium tris(bis(trimethylsilyl)amide) (In(btsa)3), which reacts with tris(dimethylamino)phosphine (P(DMA)3) and gallium iodide (GaI3) to enable the one-step, low-temperature synthesis of InGaP alloyed cores. Using this precursor, we successfully synthesized green-emitting InGaP-based core–shell QDs with a photoluminescence quantum yield (PLQY) of 74%, a full width at half-maximum (fwhm) of 43 nm, and a peak emission of 525 nm. When integrated as the emissive layer in a quantum dot light-emitting diode (QLED) device, the QDs achieved a peak luminance of 1361 cd m–2 and an external quantum efficiency (EQE) of 1.71%.