Poly(N-vinylcarbazole) (PVK) Photoconductivity Enhancement Induced by Doping with CdS Nanocrystals through Chemical Hybridization

Abstract

We have functionalized poly(N-vinyl carbazole) (PVK) by controlled sulfonation. CdS nanocystals of 3−20 nm across were synthesized in the sulfonated PVK matrix with the CdS molar fraction of ∼1−18%. The CdS nanoparticle size increased with the molar fraction of CdS. At high CdS molar fractions, the CdS nanocrystals exist in both cubic and hexagonal phases. Photoluminescence efficiency of PVK decreases when the molar fraction of CdS increases due to quenching through interfacial charge transfer. Photoluminescence attributable to the CdS nanocrystals can be observed only at low molar fractions of CdS. Significant enhancement in photoconductivity induced by the chemical doping of CdS in PVK has also been demonstrated.

Optical and Electrooptical Properties of Porous‐Silicon/Conjugated‐Polymer Composite Structures

“…0.15 V. Furthermore, two distinct behaviors have been observed under illumination (red lines in Figure 6). The appearance of a photovoltage at zero current (open-circuit voltage) for the nPSi/cPVK junction is clear indication of a type-II band alignment and the generation of charge carrier separation (see Figure 7a for a schematic view of the junction's band alignment according to the cPVK [47,48] and PSi [49][50][51] electronic structure). On the other hand, no photovoltaic effect (e.g.…”

Organic Photorefractive Materials and Applications

“…[ 130 , 144 ] The synthesis involves sulfonation of the PVK material and fabrication of a suitable precursor (PVK(SO 3 ) 2 Cd), which is followed by the nanocomposite formation. [ 145 ] Benefi ts of this approach include enhancement of photoconductivity through higher charge generation effi ciency and an increase of the lifetime of the charge carriers compared to the PVK/capped-QD blend, [ 144 ] which is ascribed to a higher interface quality. Subsequently, a two-fold increase of the gain coeffi cient Γ was demonstrated for CdSe nanocomposites compared to the blend system of PVK and 4-methylbenzenethiol capped CdSe-QD.…”

Synthesis and Anticorrosive Properties of Novel PVK-ZrO₂Nano Composite Coatings on Steel-Substrate

“…The corrosion protection offered by selfassembled films of carbazole on copper (Cu) in NaCl solution were recently studied [16]. Exploring the literature confirms that the incorporation of various nanoparticles into PVK matrix enhances properties like antimicrobial [17], charge carrier transport [18], super capacitance [19], photoconductivity [20], optical [21], electrical conductance [22], thermal stability [23] and electrochemical [24]. It is evident from the literature that few investigations were carried out in the past to validate the corrosion protection offered by the PVK nano composite films on steels.…”