Controlling the lateral and vertical dimensions of Bi2Se3 nanoplates via seeded growth

Abstract

Modulation of the morphology of nanostructures is often a rewarding but challenging task. We have employed the seeded growth method and induced kinetic control to synthesize Bi2Se3 nanoplates with modifiable morphology. By manipulating the rate at which precursor solutions were injected into seeds solution with syringe pumps, two distinctive growth modes could be realized. With a fast injection, the thickness of Bi2Se3 nanoplates slightly increased from similar to 7.5 nm (seeds) to similar to 9.5 nm while the edge length grew up from similar to 160 nm (seeds) to similar to 12 mu m, after 6 successive rounds of seeded growth. With a slow injection, the thickness and edge length increased simultaneously to similar to 35 nm and similar to 6 mu m after 6 rounds of growth, respectively. These two modes could be viewed as a competition between atomic deposition and surface migration. The products showed interesting, thickness-dependent Raman properties. In addition, NIR transparent, highly conductive and flexible Bi2Se3 thin films with different thicknesses were constructed by the assembly of the as-synthesized Bi2Se3 nanoplates. This approach based on seeded growth and kinetic control can significantly promote the development of versatile nanostructures with diverse morphology.