Covalent Layer‐by‐Layer Assembly of Conjugated Polymers and CdSe Nanoparticles: Multilayer Structure and Photovoltaic Properties

Abstract

Hybrid thin films of conjugated polymers and CdSe nanoparticles have been fabricated by using a layer‐by‐layer (LbL) approach driven by covalent coupling reactions. This method permits facile covalent crosslinking of the polymer/nanoparticle interlayers in common organic solvents, which provides a general route for preparing robust and uniform functional thin films. The deposition process is linearly related to the number of bilayers as monitored by UV‐vis absorption spectroscopy and ellipsometry. Characterization of the multilayer structures has been carried out by fluorescence spectroscopy, X‐ray photoelectron spectroscopy (XPS), and grazing‐angle Fourier‐transform infrared spectroscopy (FTIR). Techniques such as atomic force microscopy (AFM) and scanning electron microscopy (SEM) have also been used. A preliminary application of the hybrid films in the development of organic photovoltaics is presented. Upon illumination with white light at 10 mW cm–2, the self‐assembled multilayer films exhibit steady photocurrent responses with an overall optical‐to‐electrical power conversion efficiency of 0.71 %.

Ag colloids and arrays for plasmonic non-radiative energy transfer from quantum dots to a quantum well

“…Förster-type NRET is a dipole-dipole interaction between resonant donor and acceptor species and has a well-defined distance dependence [20]. NRET has been demonstrated in a large range of material systems, with potential for LED [9,[21][22][23][24][25] and light harvesting applications [2,3,13,[26][27][28][29][30][31][32][33]. QDs possess excellent optical properties such as broadband absorption with narrow and tunable emission profiles, giving them a distinct advantage over organic dyes [34,35].…”

Influence of quantum dot concentration on Förster resonant energy transfer in monodispersed nanocrystal quantum dot monolayers

“…Additionally, the LbL technique enables the realization of complex layered structures at the nanoscale on substrates of any shape and morphology and is therefore a very powerful and flexible tool. [12][13][14][15] Thus, it is used for the preparation of many different types of structures and has, in particular, shown valuable results for the preparation of light emitting and guiding structures, [24][25][26][27] photovoltaic devices, [28][29][30] sensors, and detectors. [31][32][33] Artificially designed microparticles and nanoparticles with multiple functionality can be synthesized with the help of the LbL technique and have been proposed for applications in areas such as quantum-information processing, optoelectronics, or biotechnology.…”

Preparation of nanocrystals and nanocomposites of nanocrystal-conjugated polymer, and their photophysical properties in confined geometries

“…[25][26][27] This implies that a bicontinuous and nanoscopic phaseseparated mixture of CP/QD is favorable for charge generation and transport, which is currently difficult to realize by using a conventional blending approach. [28][29][30] On the other hand, for use in LED, it is important to stabilize QDs in an appropriate host with retention of the fluorescence emission. However, possible nanoparticle aggregation in composites often limits the energy transfer pathway and leads to self-quenching of the fluorescence of QDs.…”