Controlled growth of tetrapod-branched inorganic nanocrystals

Abstract

Nanoscale materials are currently being exploited as active components in a wide range of technological applications in various fields, such as composite materials, chemical sensing, biomedicine, optoelectronics and nanoelectronics. Colloidal nanocrystals are promising candidates in these fields, due to their ease of fabrication and processibility. Even more applications and new functional materials might emerge if nanocrystals could be synthesized in shapes of higher complexity than the ones produced by current methods (spheres, rods, discs). Here, we demonstrate that polytypism, or the existence of two or more crystal structures in different domains of the same crystal, coupled with the manipulation of surface energy at the nanoscale, can be exploited to produce branched inorganic nanostructures controllably. For the case of CdTe, we designed a high yield, reproducible synthesis of soluble, tetrapod-shaped nanocrystals through which we can independently control the width and length of the four arms.

Seeded Growth of Highly Luminescent CdSe/CdS Nanoheterostructures with Rod and Tetrapod Morphologies

“…Moreover, the nucleation stage can yield nuclei with unstable structure inducing phase transitions during nanoparticle growth [8]. For example, the synthesis of nano-tetrapods is based on a delicate balance between stabilities of cubic and hexagonal phases in certain II-VI materials [8,9].…”

Nanoplasmonics and its Applied Devices

“…Scientist gained significant control both the over size [7] and surfaces [8][9][10][11][12] for nanoparticles. They have demonstrated that anisotropy in nanostructure like triangular prisms [13][14][15][16][17][18], nanoscale rods [19][20][21][22][23][24][25][26], nanoshells [27][28][29][30][31], multipods [32][33][34], disks [35][36][37][38][39] and cubes [40][41][42] shows better performance over solid spheres. …”

OPTICAL AND LUMINISCENT PROPERTIES OF Ni2+DOPED PVA CAPPED CdTe NANOPARTICLES

“…In general, there are several methods like solution cast technique, vapor phase approach, vapor liquid growth, co-precipitation method, sol-gel method , solution phase growth based on capping agents are used for the synthesis of nano-particles [2][3][4][5] . In recent scenario, tremendous effort has been done towards inorganic materials for the synthesis of nanoparticles towards a step into semiconductors due to its precise control and their size 6 , shape 7 , composition, crystal structures, strongly electronic charge carriers and also optical properties 8 . An attempt has been made to synthesize CdS and CdTe nanocrystals due to their semiconducting behavior and their unique properties 9,10 .…”