Synthesis and optical properties of two new PPV derivatives embedded on the surface of PbS nanocrystals

Probing slow dynamics by ultrafast process: Sol–gel transition detected by transient absorption spectroscopy of quantum dots

“…During the gelation process we register the evolution of the lifetimes of the excitons generated in QDs by the laser pulse. It has been shown in our previous papers [19,20] and by other authors [21] that these lifetimes are very sensitive to the environment, in which QDs are dispersed, and which in our study undergo structural transition. Moreover, since the energy band gap in semiconductor nanocrystals depends on their size [22], it can be adjusted to lie beyond the absorption range of the investigated gel.…”

“…The shorter lifetime t 1 is attributed to the transitions from the conduction band to the valence band, deep traps and shallow traps. The longer lifetime t 2 is connected with the transition from shallow traps to the valence band and to deep traps [19,[28][29][30]. The evolution of both resultant lifetimes in time of gelation is shown in Fig.…”

Studies of optical, photophysical, and thermal properties of poly(paraphenylenevinylene) (PPV) polymers with symmetric alkoxy side‐chain lengths for potential application in electronic devices

“…In this study, the synthesis of 2,5-dialkoxy poly(1,4-phenylenevinylene) derivatives (12)(13)(14)(15)(16) with various symmetric alkoxy side-chain lengths were carried out using a modified Gilch polymerization method. 16,24,[36][37][38][39] This series of compounds were prepared by altering the carbon chain length of the 2,5-bis(alkoxy) group, starting from a small propyl group to the octyl group of a larger carbon chain length. The syntheses of intermediates, monomers, and the resulting polymers 12-16 with different symmetric alkoxy side-chain lengths are shown in Figure 1.…”

Dip-coated PbS/PVP nanocomposite films with tunable band gap

“…1 Semiconducting conjugated or insulating polymers have been used as the host in PbS/polymer nanocomposites. Conjugated polymer hosts include poly[2methoxy-5-(2 0 -ethylhexyloxy-p-phenylenevinylene)] (MEH-PPV), [2][3][4][5][6][7][8] poly(2-(6-cyano-6 0 -methyl heptyloxy)-1,4-phenylene) (CN-PPP), 2 poly(3-hexylthiophene-2,5-diyl) (P3HT), 4,9-12 polypyrrole (PPy), 13 and poly[2-methoxy-5-(3 0 ,7 0 -dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV). 14 Insulating polymers, such as, polyacryl amide (PAM), 15,16 poly-p-xylylene (PPX), 17 polyacrylonitrile (PAN), 18 poly(methyl methacrylate) (PMMA), 19 polystyrene (PSt), 7,20,21 poly thiourethane (PTU), 22 polyvinyl alcohol (PVA), [23][24][25][26][27][28] poly(vinyl acetate) (PVAc), 29 poly(vinyl pyrrolidone) (PVP), 30,31 polyvinylidene uoride (PVDF), 32 and poly(ethylene oxide) (PEO) 33 have been employed as hosts.…”