Macroscale alignment of CdSe/CdS nanorods by porous anodic alumina templates

Abstract

Centimeter‐scale assemblies of highly ordered CdSe/CdS core‐shell nanorods have been successfully fabricated by infiltration of the nanorods into the pores of a transparent porous anodic alumina membrane. The high degree of the nanorod ordering is proved by the demonstration of both highly polarized PL and absorption of the aligned nanorods. The measured PL linear polarization degree is 53%. We have found that both the elongated CdS shell and the nearly spherical CdSe core exhibit a strong dependence of absorption on polarization angle with respect to the nanorod axis. We conclude that both CdS shell and CdSe core absorb more efficiently light with polarization along the axis of the nanorod. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Excitonic properties of single CdSe nanowires and coupling to plasmonic nanocavities

“…Semiconductor nanowires and nanorods have drawn increasing attention due to the tunability and high efficiency of their photoluminescence (PL) emission. Further, CdSe based nanorods (NRs) emit highly polarized light [3,4], have the potential to act as low-threshold active medium in NC based lasers and exhibit large permanent dipole moments [5][6][7][8][9][10][11]. Those colloidal CdSe based nanoemitters can be grown by wet chemical synthesis with semiconductor core sizes of 2-10 nm and passivated by a 1-2 monolayers of ZnS [12].…”

An All‐Inorganic Colloidal Nanocrystal Flexible Polarizer

“…Several techniques to generate aligned QRs have been explored for al ong time, such as electric-field-assisted assembly, [12] Langmuir-Blodgett deposition, [13] and evaporation-mediated assembly. [14] However,alarge area of well-aligned QRs cannot be obtained by these methods.Hot stretching of polymer films, [4] mechanical rubbing, [15] and template-assisted assembly [16] are promising for practical applications,and embedding QRs in astretched polymer sheet is currently the most favorable fabrication method. [4,17] However,t he stretched polymer ages under the effects of illumination, moisture,external forces,and temperature variation, leading to deterioration and loss of the orientation (see Figure S13 a).…”

Photoaligned Nanorod Enhancement Films with Polarized Emission for Liquid‐Crystal‐Display Applications

“…The alignment of NR with high‐order parameter is critically important, and several techniques have been explored in this regard, viz., evaporation‐mediated assembly, electric field‐assisted assembly, template‐assisted assembly, chemical bonding‐directed self‐assembly, LC self‐alignment, Langmuir–Blodgett deposition, mechanical rubbing, and several more . While most of these methods control the assembly of NR by an external force, they offer limited flexibility for the local alignment orientation, which reduces their prospects regarding large‐scale fabrication, required for LCD.…”

“…[5b] Furthermore, both of these approaches, in addition to many others, provide 3D NR distribution with poor in‐plane control, which limits the highest reported DOP to 0.64 for CdSe/CdS dot‐in‐rod nanostructures. [5b,13–21] Theoretically, the maximum DOP can be achieved for NR, which are uniformly aligned in‐plane (i.e., the zero pretilt angle such as shown in Figure a) with high‐order parameter.…”