Tribenzoylarsine – a Benign Arsenic Precursor for InAs Nanocrystals

III-V semiconductor nanocrystals (NCs) have emerged as a viable, more benign alternative to state-of-the-art II-VI and IV-VI NCs, which are increasingly restricted due to the toxicity of the comprising elements. While great progress has been achieved for InP, covering the visible range, the development of infrared-emitting InAs NCs has been relatively low-paced. This is due to the synthetic challenges arising from the highly covalent bonding in InAs and the small choice of available arsenic sources, which are essentially limited to tris(trimethylsilyl)arsine and tris(dimethylamino)arsine. Most importantly, wider adoption of these syntheses is hampered by their reliance on hazardous pyrophoric and costly reagents. In this work, we report for the first time the multigram synthesis of tribenzoylarsine, which can be used as a novel nonvolatile, nonpyrophoric, and hence safer, precursor for metal arsenide nanoparticles. We demonstrate that tribenzoylarsine reacts with indium oleate without additional reducing agents yielding small (~2 nm) InAs NCs. By tuning synthesis parameters (in particular, the addi-tion of zinc oleate or using continuous injection) it is possible to cover the photoluminescence range of 630–780 nm with full width at half maximum as low as 170–210 meV, which is a very competitive value to the existing synthetic approaches. Along with the significantly safer nature of tribenzoylarsine and the great potential for synthesis optimization, this makes it a very promising alternative to the currently used arsenic precursors.