# Tribenzoylarsine – A Benign Arsenic Precursor for InAs Nanocrystals

## TL;DR

A safer arsenic precursor called tribenzoylarsine is developed for making InAs nanocrystals, which could lead to safer and more efficient production of infrared-emitting materials.

## Contribution

Tribenzoylarsine is introduced as a nonpyrophoric and nonvolatile precursor for InAs nanocrystals, enabling safer and more controllable synthesis.

## Key findings

- Tribenzoylarsine reacts with indium oleate to produce ≈2 nm InAs nanocrystals without additional reducing agents.
- The method allows tuning photoluminescence to 630–780 nm with a full width at half maximum as low as 170–210 meV.
- The precursor is nonpyrophoric and nonvolatile, making it safer and more practical for InAs nanocrystal synthesis.

## Abstract

III‐V semiconductor nanocrystals (NCs) have emerged as a benign alternative to II‐VI and IV‐VI NCs, which are restricted due to the toxicity of the comprising elements. While InP NCs advanced significantly, the development of infrared‐emitting InAs NCs has been relatively slow‐paced. This is due to the synthetic challenges arising from the highly covalent bonding in InAs and the limited range of available arsenic sources. Most importantly, current syntheses rely on hazardous pyrophoric and costly reagents, which hampers their wider adoption. In this work, the synthesis of tribenzoylarsine is reported, which can be used as a novel nonvolatile, nonpyrophoric, and hence safer precursor for metal arsenide nanoparticles. Tribenzoylarsine reacts with indium oleate without additional reducing agents yielding small (≈2 nm) InAs NCs. By tuning synthesis parameters (e.g., the addition 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.

A limited choice of available organoarsenic precursors and the need to employ hazardous reagents in the synthesis are among the main reasons behind the slow‐paced development of InAs nanocrystals. Here, the multigram synthesis of tribenzoylarsine – a novel nonpyrophoric and nonvolatile precursor is reported, which reacts with indium oleate without hazardous additives yielding small InAs nanocrystals.