Synthesis and elucidation of local structure in phase-controlled colloidal tin phosphide nanocrystals from aminophosphines

The chemical versatility and rich phase behavior of tin phosphides has led to interest in their use for a wide range of applications including optoelectronics, thermoelectrics, and electrocatalysis. However, researchers have identified few viable routes to high-quality, phase-pure, and phase-controlled tin phosphides. An outstanding issue is the small library of phosphorus precursors available for synthesis of metal phosphides. We demonstrated that inexpensive, commercially available, and environmentally benign aminophosphines can generate various phases of colloidal tin phosphides. We manipulated solvent concentrations, precursor identities, and growth conditions to obtain Sn3P4, SnP, and Sn4P3 nanocrystals. We performed a combination of X-ray diffraction and transmission electron microscopy to determine the phase purity of our samples. X-ray absorption spectroscopy provided detailed analyses of the local structures of the tin phosphides.

Automated summary

The chemical versatility and rich phase behavior of tin phosphides have attracted researchers' interest for various applications. However, there are few viable methods to obtain high-quality and phase-controlled tin phosphides. In this study, we demonstrated that inexpensive and commercially available aminophosphines can be used to synthesize different phases of tin phosphides. We manipulated various factors to obtain phase-pure Sn3P4, SnP, and Sn4P3 nanocrystals. The phase purity was confirmed by X-ray diffraction and transmission electron microscopy.