Elemental Nanocrystal Redox Pathway Enables Antimonide Colloidal Quantum Dots.

Colloidal quantum dots (QDs) with exceptional size-tunable optoelectronic properties enable a wide variety of optical and optoelectronic applications. Although established synthetic methods have advanced QD technologies, extending these strategies to highly coveted antimonide-based QDs persists as an unresolved challenge. Here, we develop an innovative "elemental nanocrystal redox (ENR)" strategy using zero-valent nanocrystals (NCs) as precursors, enabling the synthetic control of size-tunable colloidal antimonide QDs without the need for size-selection. The ENR strategy achieves synthetic control over InSb QDs with pure crystal structure and mid-infrared absorption exceeding 3000 nm. Furthermore, the versatility of the ENR strategy extends to the rarely reported GaSb and InGaSb alloyed QD systems. The results presented here significantly enrich the modulatory dimensions of colloidal synthesis and pioneer a new pathway for exploring other exotic colloidal nanomaterials that have previously posed significant synthetic challenges with traditional strategies.