Carboxylate‐Driven Synthesis of InSb Quantum Dots With Broad Short‐Wavelength Infrared Emission Tuning

We report here a new precursor‐based approach for synthesizing colloidal indium antimonide quantum dots (InSb QDs) that emit light in the short‐wavelength infrared (SWIR) region. The synthesis was carried out using indium and antimony carboxylates. Antimony(III) acetate was converted into Sb(PA) ₃ and Sb(LA) ₃ (PA = palmitic acid, LA = lauric acid) to improve their solubility and stability in octadecene (ODE). The synthesis employed air‐stable tris(dimethylamino)phosphine as the reducing agent, enabling a safer and milder reaction. X‐ray powder diffraction confirmed the formation of single‐phase InSb without any impurity phases. By controlling the ligand chain length and the purification conditions, we obtained size‐tunable photoluminescence (PL) spectra with peak wavelengths ranging from 870 to 1510 nm. Shorter alkyl ligands and the addition of trioctylphosphine facilitated the growth of larger particles, leading to a redshift in the PL spectra. This study demonstrates that precursor and ligand design can effectively control the particle size and optical properties of InSb QDs, providing a versatile synthetic route for developing III–V semiconductor QDs with tunable emission across a broad SWIR wavelength range.