ZnS Samples Research Articles

All-Solid-State Post-Compression of Low-Energy Pulses at High Repetition Rate

We demonstrate a proof of principle of a simple all-solid-state post-compression setup for low-energy, high-repetition-rate laser pulses, where spectral broadening was performed using a combination of highly nonlinear bulk materials in a simple single-pass geometry. The 75 fs, 210 nJ pulses from an amplified 76 MHz, 15.7 W Yb:KGW oscillator after sequential spectral broadening in ZnS and YAG samples of 2 mm and 15 mm thickness, respectively, were compressed to 37 fs by means of Gires–Tournois interferometric mirrors. The post-compressed pulses with an average power of 11.47 W demonstrated reasonable spatial-spectral homogeneity of the beam with the spectral overlap parameter V>83% and good beam quality with Mx2=1.28 and My2=1.14.

Effects of Gamma-ray and neutron irradiation on infrared optical properties of ZnSe and ZnS for ITER divertor thermography

Gamma-ray and neutron irradiation tests were performed by using antireflective-coated and non-antireflective-coated samples of ZnSe and ZnS to examine the impact on their infrared optical properties. In neutron irradiation tests, ZnSe and ZnS samples showed minimal transmittance reduction even up to 1.44 × 1016 n/cm2 (evaluated by dpa value, the values are 5.77 × 10−6, 2.07 × 10−5 for ZnSe and ZnS, respectively), about 5.8 times higher than the expected neutron fluence in ITER. Gamma irradiation at 100 kGy did not affect any of the samples, however, at 5.6 MGy (2.6x the expected dose of ITER), non-antireflective-coated ZnSe and ZnS exhibited induced absorption bands. Antireflective coating did partially mitigate this effect, but ZnS, even with antireflective coating, showed up to 2.5 % degradation over the wide wavelength range of 1.5–4.5 µm, whereas ZnSe was less affected. Both ZnSe and ZnS exhibited a modest 2 % absorption around 3 µm. Surface analysis by SEM, laser microscope, and XPS linked the 3-µm degradation to gamma-irradiation-induced Zn(OH)2 formation that was confined to the surface. Thus, transmittance degradation of ZnSe over the lifespan of ITER was estimated to be a maximum of approximately 7.8 %. The practical use of ZnSe in the IRTh system requires further evaluation with Si and CaF2 lenses and for the optical design to be finalized. Nevertheless, these findings suggest that ZnSe is a promising candidate for the IRTh system's lenses.

Corrosion Resistance of NiS, ZnS and NiS/ZnS Thin Films Deposited by Spray Pyrolysis Technique on Low Carbon Steel in 3.5% Nacl Solution

Abstract In this work, the main object of this research is to investigate a new material based on ZnS and NiS nanostructures. NiS and ZnS solutions were sprayed on the heated Low Carbon Steel by a spray pneumatic deposition method. Electrochemical analyses of the prepared samples were investigated. The high corrosion resistance of coated by ZnS sample have a low value of surface roughness. However, the coated sample by ZnS also has good stabilization after corrosion and high compact of the film.

ZnS nanoparticles prepared by Prunus persica leaf extract: Morphological, optical and electrical properties

As compared to conventional physical and chemical techniques, the biological method (green synthesis) is an economical, nontoxic, fast, eco-friendly and cost-effective technique that utilizes plant extract to generate highly stable and biocompatible nanoparticles. The existing study focuses on the synthesis of zinc sulphide nanoparticles (ZnS NPs) using P. persica leaf extract which is used as a reducing agent and their associated properties. The prepared samples were examined in terms of structural, optical, morphological and compositional properties. The SEM images showed the agglomerated spherical particles while XRD spectra confirmed the hexagonal (wurtzite) phase of synthesized ZnS samples with average crystallite sizes found to vary from 12.45 to 14.36[Formula: see text]nm. The optical absorption spectra displayed the absorption peaks at 331[Formula: see text]nm (4.26[Formula: see text]eV) and 339[Formula: see text]nm (4.10[Formula: see text]eV). This blue shift in the absorption band suggests the formation of ZnS NPs compared with bulk ZnS ([Formula: see text][Formula: see text]eV) material. The FTIR peaks from 612– to 630[Formula: see text]cm[Formula: see text] and 860– to 1022[Formula: see text]cm[Formula: see text] are because of the symmetric bending vibrations of the Zn–S bands. Electrical measurements showed that the resistivity is found to be decreasing with increasing temperature, signifying the semiconducting behavior of the synthesized ZnS NPs. The findings of this study suggest the feasible use of P. persica leaves extract for the production of ZnS NPs which could be utilized as multifunctional material in medical applications, biosensors, photocatalytic and electrical applications.

Influence of molar concentration on structural, morphological, optical and luminescence of polyvinyl alcohol-capped nanostructured ZnS films

Nanostructured ZnS films of various molar concentrations have been deposited using chemical bath deposition (CBD) method on glass substrates in the matrix of polyvinyl alcohol (PVA). Structural analysis of the samples with the help of X-ray diffraction (XRD) shows that the films are of cubic phase structure and diffraction peaks shift toward higher diffraction angle with the increase of molar concentration. Crystallite size is obtained using Scherrer’s formula, Williamson–Hall (WH) plot as well as size–strain plot (SSP), and reveals decrease in size with increasing molar concentration. Surface morphology and surface texture of the samples are observed with the help of atomic force microscopy (AFM) and high-resolution transmission electron microcopy (HRTEM) which exhibit the roughly spherical shape of the particles as well as formation of cluster by a large number of ZnS nanoparticles. Observation from selected area electron diffraction (SAED) pattern also confirms the cubic phase of nanostructured ZnS samples. Surface topographic study using scanning electron microscopy (SEM) also shows particle agglomeration forming nanoclusters and energy-dispersive X-ray spectroscopy observation reveals that the films are composed of zinc and sulfur. With the increase of molar concentration, the optical bandgap energy increases whereas the refractive index as well as dielectric constant decrease, and in comparison to ZnS bulk counterpart, the samples are found to be blue-shifted. Samples exhibit blue emission photoluminescence (PL) band and second-order Raman scattering. Fourier-transform infrared (FTIR) technique is utilized to detect the presence of stabilizing agent.

Structural and Electrical Studies on ZnS Quantum Dots Using PEG as Capping Agent

AbstractZinc sulfide (ZnS) nanoparticles are produced in this study utilizing a simple wet‐chemical precipitation procedure using polyethylene glycol (PEG) as a capping agent. To analyze the structural, morphological, electrical, and electronic properties of the material, the ZnS nano powder is studied using X‐ray diffraction (XRD), scanning electron microscopy (SEM), FTIR, UV–visible absorption spectroscopy, and impedance spectroscopy techniques. The XRD patterns confirm the formation of the cubic phase in as‐prepared ZnS samples, whereas SEM and AFM images show the formation of prismatic and spherical morphology of nano crystallites, confirming the XRD results. FTIR spectra confirm formation of ZnS stoichiometric compound with a partial shifting of vibration bands in the presence of PEG in precursor solution. Optical band gap spectra show a blue shift of band gap with decrease in particle size. The controlled growth kinetics in the presence of PEG the ZnS synthesized nanoparticles show a better quantum confinement effect and enhancement of electrical conductivity behavior as predicted from impedance measurements. For the temperature range of the current investigation, the temperature dependence of conductivity is found to obey the Davis‐Mott model.

Cobalt-substituted ZnS QDs: a diluted magnetic semiconductor and efficient photocatalyst.

Recently, understanding the origin of induced magnetic characteristics in transition metal atom-doped QDs has been a major focus owing to their potential applications in the area of spintronic devices. A detailed experimental and theoretical investigation was conducted to understand the physical properties of Co-doped ZnS QDs containing different weight percentages of Co atoms [CoxZn1-xS (x = 0.00, 0.03, 0.06, and 0.09)], prepared using chemical co-precipitation techniques. X-ray diffraction studies proved that all the prepared QDs formed an extremely pure cubic zinc blende crystallographic phase free of contaminants. The validation of the quantum dot nature of all the samples was provided by the HRTEM images, BET studies, and blue shift in the absorption spectra. Both the obtained FTIR and PL spectra at room temperature also confirmed the phase purity of the prepared QDs. The observed weak ferromagnetic behavior of the doped samples was due to the presence of p-d hybridization between the 3d levels of Co2+ ions and 3p levels of S2- ions of the host ZnS QDs. Hysteresis loops that were obtained at room temperature validated this weak ferromagnetic nature. These obtained results were also supported theoretically using DFT calculations. FDTD simulations provided a detailed explanation for the observed blue shift in the absorption spectra originating from the quantum confinement effect of doped and undoped ZnS QDs. The dielectric properties of all the samples were examined properly, and it was also found that the grain boundaries contributed effectively to providing the dielectric response. The doped ZnS sample containing more Co dopants at low frequencies showed a progressive rise in polarisation loss. In addition, Co-doped ZnS QDs are efficient photocatalysts. A pH-dependent photodegradation test of ciprofloxacin (CIP) antibiotic was conducted using 9% Co-doped ZnS QDs. It was observed that 9% Co-doped ZnS nanocatalysts has sufficient capability to degrade CIP to around 94.7% in a solution of pH 10 within one hour. Therefore, besides showing photocatalytic effects, Co-doped ZnS QDs act as ideal dilute magnetic semiconductors (DMSs) and will undoubtedly become excellent candidates for the microelectronics industry because of their special ability to exhibit spin-dependent magneto-electro-optical properties that find use in spin-polarized light-emitting diodes, solid-state lasers, and spin-transistor devices.

Hierarchical ZnS layers-coated Ti3+-TiO2 nanostructures for boosted visible-light photocatalytic norfloxacin degradation

Self-doped Ti3+-TiO2 and amorphous ZnS layers-coated Ti3+-TiO2 nanostructures were successfully fabricated for via a calcination-ultrasonic synthesis strategy for organic pollutant degradation under visible-light illumination. The experimental results revealed that the synthesized Ti3+-TiO2 clusters displayed efficient visible-light absorption and photocatalytic performance. It was also found that amorphous ZnS layers were formed on the coral-like Ti3+-TiO2 clusters via an ultrasonic synthesis method, and the strongly combined interfaces greatly boosted the charge separation between ZnS layers and self-doped Ti3+-TiO2 clusters. The synthesized Ti3+-TiO2@ZnS-15% heterojunction presented the highest photocatalytic activity with a rate constant of 0.03197 min−1, approximately 9.87 times of commercial TiO2. In addition, the prepared Ti3+-TiO2@ZnS composites also exhibited highly boosted photocatalytic performance towards ciprofloxacin and tetracycline degradation under visible-light illumination compared with those of commercial TiO2, Ti3+-TiO2, and ZnS samples. Finally, the norfloxacin degradation pathways and visible-light photocatalytic mechanism over nanostructured Ti3+-TiO2@ZnS heterojunctions were suggested.

Phase transition in ZnS nanoparticles: electrical, thermal, structural, optical, morphological, antibacterial and photocatalytic properties

Zinc Sulphide nanoparticles (ZnS-NPs) are synthesized by microwave assisted chemical precipitation method. The as-synthesized nanoparticles are identified by X ray diffraction and electrical studies to examine the structural transition. The HT-XRD at 1000 C (373 K) and 2000 C (473 K) of ZnS-NPs also confirms structural transition of cubic to hexagonal phase. Thermal properties of the ZnS sample is also studied using thermo gravimetricdifferential thermal analysis (TG-DTA). From D.C. electrical resistance, a discontinuity occurs in the temperature resistance curve of the ZnS-NPs due to phase transition around 450 K. The energy dispersed x-ray analysis and Raman spectra of the ZnS-NPs confirm the presence of zinc and sulphur. The optical studies of the prepared ZnS-NPs are confirmed by its UV-vis and PL spectra. The TEM image of cubic ZnS-NPs reveals the well distribution of spherical shaped particles with mean size of 12.52 nm with standard deviation of 9.326 nm. According to the photocatalytic results of ZnS-NPs for the degradation of methylene blue (MB) have the highest degradation efficiency of 93.24% under UV irradiation within 80 min. Antibacterial effects of ZnS-NPs nanoparticles against some pathogens, like gram-negative, gram-positive, E. coli (Escherichia coli), S. aureus (Staphylococcus aureus) bacteria.

Microwave-assisted synthesis and characterization of undoped and manganese doped zinc sulfide nanoparticles

Undoped and Mn-doped ZnS nanocrystals were produced by the microwave-assisted solvothermal method and characterized by X-ray diffraction, photoluminescence spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy. All samples have the cubic zinc blende structure with the lattice parameter in the range of a = 5.406–5.411 Å, and the average size of crystallites is in the range of 6–9 nm. These nanoparticles agglomerate and form large grains with an average size of up to 180 nm. The photoluminescence of the undoped ZnS sample shows a broad emission band located at 530 nm, attributed to the defects at the surface of nanoparticles. In all Mn-doped samples, the emission peak at 598 nm was observed assigned to the characteristic forbidden transition between excited (4T1) and ground (6A1) levels of Mn2+. Synchrotron radiation X-ray absorption spectroscopy at the Zn and Mn K-edges combined with reverse Monte Carlo (RMC) simulations based on the evolutionary algorithm confirms that manganese ions substitute zinc ions. However, the difference in the ion sizes (R(Mn2+(IV)) = 0.66 Å and R(Zn2+(IV)) = 0.60 Å) is responsible for the larger interatomic distances Mn–S (2.40(2) Å) compared to Zn–S (2.33(2) Å). The static structural relaxations in ZnS:Mn nanoparticles are responsible for the large values of the mean-square displacements factors for Zn, S and Mn atoms obtained by RMC simulations.

Structural, optical and radiation shielding properties of ZnS nanoparticles QDs

In this paper, the structural, optical and radiation shielding properties of ZnS nanoparticles (NPs) Quantum Dots (QDs) were studied by changing the molarity of the sulfur source used for the synthesis. The molarity change method of the sulfur source is suitable for the fabrication of ZnS nanoparticles of different sizes. X-ray diffraction (XRD), transition electron microscopy (TEM), Fourier transform infrared spectrophotometer (FTIR), Photoluminescence (PL) and UV–visible spectroscopy were used to study the structure and optical properties of ZnS QDs. XRD analyses exhibit cubic structure with the average crystallite size in the range (3.8–2 nm). The spherical shape is observed from TEM images. Analyses of FTIR and PL emission peaks, with different molarity of the sulfur source, confirmed the structural deformation resulting from the different concentrations of S. The analyses of absorption spectra measured by UV–visible spectroscopy indicated a strong quantum confinement effect for the ZnS samples prepared with different molarity of S source. The linear attenuation coefficient (LAC), half-value layer (HVL), tenth value layer (TVL) and the mean free path (MFP) at the photon energy from 0.015 to 15 MeV, were evaluated using Phy-X / PSD software program. It is found that the LAC increases with increasing nanoparticle size, while HVL, TVL and MFP decrease as the particle size decreases. Moreover, the fast neutron removal cross-section ƩR has been evaluated.

Green synthesis of ZnS nanoparticles using allium sativum l. extract and study of their structural, optical and electrical properties

This work presents a simple, low-cost and environmentally friendly approach for the synthesis of zinc sulfide nanoparticles (ZnS NPs) using Allium sativum L. plant extract. Formation of cubic ZnS NPs is confirmed from X-ray diffraction study. Transmission electron microscopy image confirms the formation of spherical particles of average size 6.5 nm. Direct band gap energy of the NPs is found to increase from 3.87 – 4.25 eV with increasing volume of the extract. Fourier transform infrared spectroscopy analysis confirms the presence of biomolecules in the extract which are involved in the formation of ZnS NPs. The possible growth mechanism of ZnS NPs within the biopolymer matrix has been discussed. The dielectric constant of ZnS NPs is higher than the bulk ZnS. A.C. conductivity increases with increasing frequency and changes practically linearly with applied frequency. The impedance study suggests that the ZnS samples could be used as nano-tuned devices in electronics. It is found that as crystallite size decreases, d.c conductivity rises.

Structural and Optical Studies of Synthesized Semiconductor NixZn1-xS Nanostructure Thin Films for Optoelectronic Device Applications

Transition metal ions like Nickel doped ZnS semiconductor materials have a wide range of optoelectronic device applications. However, the doping concentration effect on the properties of NixZn1-xS has not been reported. This study, therefore, investigated the effects of nickel (Ni) doping concentration on the structural and optical properties of synthesized NixZn1-xS nanostructured thin films prepared by low-cost Chemical Spray Pyrolysis (CSP) technique. NixZn1-xS nanostructured thin films with a thickness of 320nm and different mole ratios (𝑥 = 0.00, 0.02, 0.04, 0.06 and 0.08,) were grown by the use of spray solution on hot glass substrates at a temperature of 300oC using CSP technique. The spray solutions contain nickel acetate, zinc acetate, and thiourea as precursors for Nickel, Zinc, and Sulphur, respectively. The influence of Ni doping concentration on the structural, optical, and morphological properties were investigated using X-ray diffraction (XRD), Ultraviolet-Visible spectroscopy (UV-vis) and Scanning Electron Microscopy (SEM) respectively. The XRD analysis indicated that all the prepared films retained the ZnS cubic zinc blend structure. SEM results show that the films are composed of well crystalline grains with various shapes and densely bound to each other. The UV-vis spectroscopy shows that transmittance is moderately high and increased with increasing Ni content. The average transmittance of NixZn1-xS are 61.3%, 62.8%, 63.9%, 67.6 and 69.6% for x = 0.00, 0.02, 0.04, 0.06 and 0.08, respectively. The bandgap of Ni-doped ZnS samples is low compared to the undoped, and the value increases gradually with increasing Ni concentration. Based on the results obtained, with the enhanced structural and optical properties, NixZn1-xS films could be a useful material in the future of optoelectronic applications.

Tuning the properties of ZnxS1-x nanoparticles by controlling reaction conditions

In this work, a modified synthesis method was deployed to obtain nanocrystalline zinc sulfide from zinc acetate. By utilizing the hydrothermal and sol gel method, the influence of: reaction time, solvent and temperature control were used to tune the properties of zinc sulfide. Our results showed that ZnS(B) (which was obtained by sol gel in water + hydrothermal) typified formation of increased sulfur vacancies while an increase in reaction time resulted in decreased sulfur vacancies. The introduction of chemical defects in ZnS(A) (which was obtained by sol gel in methanol + KOH) resulted in lower crystallite size. We observed that crystallinity improved with increased reaction time and utilization of water as solvent improved the crystallinity of the material as confirmed in ZnS(C) and ZnS(B). Furthermore, our result showed that reaction time influenced dislocation density of the material to a greater extent than type of solvent used. The crystallite size estimated by Scherer formula was in the range 1.35 nm – 18.64 nm while the band gap energy of the ZnS samples were calculated in the range 3.8 eV- 4.6 eV. Utilizing these novel syntheses methods can stimulate new directions in synthesizing ZnS crystals with options of choosing appropriate method for specific applications depending on properties to be traded off.

High sensitive samarium-doped ZnS thin films for photo-detector applications

We developed the ZnS and samarium-doped ZnS thin films for photo-detector applications via a simple Nebulizer Spray Pyrolysis technique. The structural, morphological, optical, and photo-detecting behavior of ZnS and Sm-doped (0.5, 1.0, and 1.5%) ZnS thin films were characterized by XRD, Raman, AFM, UV–Vis, and Keithley analyzer measurements. The XRD analysis confirms the hexagonal wurtzite structure with the polycrystalline nature of all the samples. This wurtzite nature of ZnS:Sm was also confirmed by E1 (LO) phonon mode present at 346 cm −1 in the Raman spectrum. AFM images and thickness measurement depicted enrichment of particles on the surface. The presence of constituents in the samples was identified by EDX analysis. The semiconducting nature of the prepared films was exhibited by optical studies and it shows the lowest optical band gap ( E g ) value for the 0.5% Sm-doped ZnS (3.35 eV) thin film. Photo-sensing measurements was carried out by Keithley analyzer and showed the enhancement of sensing parameters up to 0.5% of Sm doping and then decreases for higher concentrated ZnS:Sm. The highest value of Responsivity ( R) , EQE, and Detectivity ( D *) was 8.30x10 −2 AW −1 , 28.26%, and 2.42 × 10 10 Jones, respectively for as-prepared 0.5% Sm-doped ZnS. Hence, it clearly depicts that the doping of a small amount of samarium highly alters the host lattice and their photoconducting mechanism. • Development of high-performance photodetector based on Sm@ZnS has been presented. • The grown films are of good crystallinity. • Surface morphology of the pure and Sm-doped ZnS samples was identified by AFM. • Good optical transparency and variation in bandgap values of Sm:ZnS films was noticed. • Responsivity ( R) , EQE and Detectivity ( D *) are highest for 0.5% of Sm-doped ZnS film.

Influence of Synthesis Temperature on the Phases Developed and Optical Properties of Manganese Sulfide and Zinc Sulfide

AbstractNano MnS and ZnS samples are prepared through a simple thermolysis procedure. The effect of synthesis temperature on the different phases formed and their percentages, and on the lattice parameters and crystallite size of MnS and ZnS is examined using Rietveld analysis for X‐ray diffraction patterns. The minimum synthesis temperature at which MnS can be formed by the present simple procedure is 250 °C, while ZnS can be prepared at a lower temperature of 200 °C. For manganese sulfide, traces of Mn3O4 phase appear at 300 °C and increase with temperature, while ZnS resists oxidation until 500 °C; pure ZnO forms at 700 °C. The MnS and ZnS samples, obtained at all temperatures, are found to be biphasic; cubic and hexagonal. The nano nature of the samples and the particle morphology are investigated by high‐resolution transmission electron microscopy. Fourier‐transform infrared spectroscopy is applied to follow the characteristic vibration bands in both systems. The values of the different energy gaps depend on the crystallite size, phases’ percentages, and the preparation temperature. The photoluminescence intensity and the emitted colors from MnS and ZnS depend on the synthesis temperature.

Optical properties of Silica capped Mn doped ZnS quantum dots

In the present report, silica capped ZnS quantum dots (QDs) have been synthesized using one-step Stober process. The bare Mn doped ZnS samples have been prepared by the co-precipitation method. The samples have then been coated by a SiO2 layer. X ray diffraction have been used to confirm the presence of desired phases and the absence of any impurity phase. The particle size and morphology have been studied through high resolution transmission electron microscopy (HRTEM). The absorption and the emission properties of the bare and the capped samples have been studied through UV-visible and photoluminescence spectroscopy respectively. Fourier-transform infrared (FTIR) spectroscopy was employed to study the band resonances of the samples.

Study on the Photoluminescence Properties and First-Principles Calculations of L-cysteine Capped ZnS Quantum Dots

L-cysteine (L-cys) was used to coat ZnS quantum dots (QDs), which should benefit the improvement of water solubility and photoluminescence (PL) intensity of ZnS QDs. The impact of L-cys on the performances of ZnS QDs and the corresponding mechanism were discussed. It illustrated that L-cys modification didn’t change the crystal structure of ZnS QDs, and the mean diameter was enlarged as the content of L-cys was more. The results also displayed that the water solubility and PL intensity of samples coated with L-cys was better than that of the uncoated sample. The sample exhibited the maximal emission while the weight ratio of L-cys to QDs equaled 1.4:0.5, and it was 4.5 times as strong as ZnS sample. The result of the First-principles calculations indicated that L-cys shell layer is beneficial to prolong the lifetime of photon-generated carriers at surface location, which should lead to a reduction in the nonradiative recombination on the surface, and then the PL intensity will be enhanced. This work helps to investigate the surface modification of QDs modified by other organic compounds.

Structural, optical, and magnetic properties of Mn-doped ZnS nanoparticles

Undoped and Mn-doped ZnS nanoparticles were successfully prepared through a coprecipitation method at low-temperature processing. The X-ray diffraction patterns reveal that the undoped and Mn-doped ZnS nanoparticles have polycrystalline nature with cubic ZnS structure. Furthermore, the lattice constant of the ZnS nanoparticles increases with an increase in the Mn doping concentration. Transmission electron microscope images demonstrated the as-synthesized nanoparticles have particle size ranging from 3 to 5 nm with spherical-shaped particles. Optical band gap values were found to increase from 3.32 to 3.50 eV with the increasing Mn doping concentration. The magnetic properties of undoped and Mn-doped ZnS samples were studied using the vibrating sample magnetometer at room temperature. The synthesized undoped ZnS nanoparticles exhibit ferromagnetism, while Mn-doped ZnS nanoparticles showed paramagnetism at room temperature. Moreover, the saturation magnetization of Mn-doped ZnS samples is higher compared to undoped ZnS. The present synthesis technique to produce high-crystalline quality Mn-doped ZnS nanoparticles and prepared nanoparticles has great potential applications in spintronic and optoelectronic devices.

Influence of chromium incorporation on optoelectronic and magnetic properties of Zn1−xCrxS nanocrystals

A series of Zn1−xCrxS powder with (x = 0–0.18) has been obtained by hydrothermal synthesis. Hexagonal phase nanocrystalline structure of powder samples has been emphasized by X-ray diffraction (XRD) showing particle size ranging from ~ 7 to 11 nm. FE-SEM confirms the nanostructure nature of samples. Elemental compositional analysis confirmed the accurate atomic percentage of existing elements using EDX technique. FTIR spectra of Zn1−xCrxS powder samples indicate different bands corresponding to their structure. The fundamental optical bandgap transition observed at 3.36 eV and additional transitions exist for Cr-doped ZnS samples. Photoluminescence (PL) emission spectra of Zn0.82Cr0.18S nanoparticle powder pumped with different excitation wavelengths (200–290 nm) showed different emission peaks, the highest intensity peak at 398 nm is due to fundamental transition of bandgap which agree with the optical results. The sample with x = 0.11 displays the most intense PL signal. Diamagnetic behavior was observed for ZnS compound whereas ferromagnetic behavior was observed for ZnS-doped with Cr.