Doping poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene]with PbSe nanoparticles or fullerenes

Abstract

The positions of the molecular orbitals of the conjugated semiconducting polymer, poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), relative to the Fermi level, shift when lead selenide (PbSe) quantum dots or the fullerene based molecule [(6)]-1-(3-(methoxycarbonyl)propyl)-[(5)]-1-phenyl-[5,6]-C61, known as PCBM, are dispersed in the polymer host. This is evident from the consistent shifts of occupied molecular orbitals and the valence band edge to greater binding energies and a decrease in density of states near the Fermi level, as probed by photoemission. In the case of PbSe nanocrystal quantum dots, far smaller binding energy shifts were observed. This behavior seems more characteristic of a charge donor, though PbSe and PCBM should act as charge acceptors. In the case of both dopants, what doping does exist occurs only with small concentrations (<10%). MEH-PPV doped with a large-Z semiconducting material, such as PbSe nanocrystal quantum dots, is a candidate for use as a good gamma radiation detector.

Narrow bandgap colloidal metal chalcogenide quantum dots: synthetic methods, heterostructures, assemblies, electronic and infrared optical properties

“…Chambers et al 384 have also investigated the use of PbSe NCs with MEH-PPV as potential gamma radiation detectors. Fo ¨rster resonance energy transfer from NCs to polymer results in visible emission which is linearly proportional to the gamma radiation dose.…”

Polymeric nanocomposites containing non-covalently bonded fullerene C60: properties and applications

“…Further development of works on polysilanes 104,105 and polyphenylenevinylenes [106][107][108][109][110][111] not only met all optimistic expectations, but also led to new interesting and, in some cases, unique, results. For example, conditions for the preparation of thin films based on fullerene-modified polyphenylenevinylene (the content of fullerene is 7-40 vol%) were found.…”

“…Conditions for the preparation of composites based on polyphenylenevinylene and fullerene C 60 with improved all photovoltaic parameters were specified. 110,111 Impressive improvement in electric and/or optical characteristics was also observed for fullerene-doped polythiophenes, [111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126] PI, [127][128][129][130][131] and polyaniline. [131][132][133][134][135] Thin films based on polysilane were recommended for use in photodiodes and optical shutdown systems.…”