Band structure engineering via piezoelectric fields in strained anisotropic CdSe/CdS nanocrystals.

ABSTRACT: Strain in colloidal heteronanocrystals with non-centrosymmetric lattices presents a unique opportunity for controlling optoelectronic properties and adds a new degree of freedom to existing wavefunction engineering and doping paradigms. We synthesized wurtzite CdSe nanorods embedded in a thick CdS shell, hereby exploiting the large lattice mismatch between the two domains to generate a compressive strain of the CdSe core and a strong piezoelectric potential along its c-axis. Efficient charge separation results in an indirect ground-state transition with a lifetime of several microseconds, almost one order of magnitude longer than any other CdSe/CdS nanocrystal. Higher excited states recombine radiatively in the nanosecond time range, due to increasingly overlapping excited-state orbitals.

SUBMITTER: Christodoulou S 

PROVIDER: S-EPMC4532876 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature