Photo-catalytic activity of Zn1-x Mn x S nanocrystals synthesized by wet chemical technique

Abstract

Polyvinyl pyrrolidone capped Zn1-xMnxS (0 ≤ x ≤ 0.1) nanocrystals have been synthesized using wet chemical co-precipitation method. Crystallographic and morphological characterization of the synthesized materials have been done using X-ray diffraction and transmission electron microscope. Crystallographic studies show the zinc blende crystals having average crystallite size approx. 3 nm, which is almost similar to the average particle size calculated from electron micrographs. Atomic absorption spectrometer has been used for qualitative and quantitative analysis of synthesized nanomaterials. Photo-catalytic activity has been studied using methylene blue dye as a test contaminant. Energy resolved luminescence spectra have been recorded for the detailed description of radiative and non-radiative recombination mechanisms. Photo-catalytic activity dependence on dopant concentration and luminescence quantum yield has been studied in detail.

The photoluminescence enhancement of Mn2+ ions and the crystal field in ZnS:Mn nanoparticles covered by polyvinyl alcohol

“…Recently, Mn doped ZnS nanoparticles (denoted by ZnS:Mn) is widely used in photonic, biological markers, photocatalytic applications and many other applications because they are wide band gap semiconductors with stable and strong PL intensity in the yellow-orange region and high luminescent efficiency (Bhargava et al 1994;Bhargava 1996;Pouretedal et al 2009;Chitkara et al 2011;Sajan et al 2015).…”

“…ZnS:Mn nanoparticles were often capped by surface active substances such as C 2 H 4 O 2 S thyoglycolic acid, (C 6 H 9 NO) n polyvinyl pyrrolidone (PVP) and [CH 2 CH(OH)] n polyvinyl alcohol (PVA) 3-mercaptopropionic acid (MPA) (Chitkara et al 2011;Onwudiwe et al 2014;Murugadoss 2010;Murugadoss et al 2010;Thi et al 2013;Hirankumar et al 2005;Kareem et al 2012;Zhou et al 2015). Meanwhile, ZnS:Mn nanoparticles isolated with the environment, un-aggregation, thus the particle size reduced.…”

Influence of Co-Dopant on Structural, Optical and Electrochemical Properties of Zinc Sulphide Quantum Dots

“…As far as prepared samples are concerned, Co +2 and Ni 2+ serves as trap state for ZnS. When the charge carriers are generated under visible light irradiation, there exist a competition between charge carrier recombination and charge carrier trapping, followed by competition between recombination of trapped carriers and interfacial charge transfer [27]. For efficient photodegradation, the charge carrier trapping, followed by interfacial charge transfer should predominate the charge carrier recombination.…”

Influence of Polyvinyl Pyrrolidone on Absorption and Radiation Transitions of Mn\(^{2 + }\) ions in Mn-doped ZnS Nanoparticles

“…6(a)). These bands could be assigned to the absorption transitions of 3d 5 electrons from 6 A 1 ( 6 S) ground state to 4 E( 4 D), 4 T 2 ( 4 D), 4 A 1 ( 4 G)-4 E( 4 G) and 4 T 2 ( 4 G) excited states of Mn 2+ cations in ZnS host lattice, respectively [15]. For PVP-capped ZnS:Mn nanoparticles with mass from 0.3 to 0.8 g, the intensity of these bands increased and achieved the maximum at mass equal 0.7 g (see Fig.…”

“…Under ultraviolet radiation, the PVP chain's electrons can be excited to transit between HOMO and LUMO levels, then collide with host lattice and emit radiation [2]. Therefore, PVP is widely used as a surfactant in order to prevent agglomeration and stabilize particle size, while simultaneously increase the emission intensity of the host matrices [3,4]. In this paper, c 2015 Vietnam Academy of Science and Technology we present the study of influence of PVP binding on the excitation characteristics of ZnS:Mn nanoparticles prepared by mean of the co-precipitation technique.…”