Synthesis and Photovoltaic Properties of Cd₃As₂ Faceted Nanoplates and Nano-Octahedrons

Recent theoretical predictions and angle-resolved photoemission spectroscopy measurements have shown that single crystal Cd₃As₂ is a three-dimensional topological Dirac semimetal possessing linear dispersions along all three momentum directions. Nanoscale topological Dirac semimetal structures have a large surface-to-volume ratio and provide a platform to explore its topological surface states. Here we report the synthesis of high quality Cd₃As₂ single crystalline nanoplates and nano-octahedrons via a vapor–solid growth mechanism. Triangular and hexagonal nanoplates with lateral dimensions ranging from several hundred nanometers to tens of micrometers are obtained. The top facets are (112), consistent with the natural cleavage plane of Cd₃As₂ single crystal. The synthesized Cd₃As₂ nano-octahedrons are enclosed by the {112} facets. A photovoltaic effect is demonstrated from a Cd₃As₂ nanoplate/metal electrode interface, suggesting potential applications in self-powered photodetection