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The current study is on the deposition of Zinc Sulfide and Cadmium Sulfide thin films by chemical bath deposition (CBD) technique. The deposited films were annealed at 200 °C and 350 °C in vacuum system. The Structural, Surface morphology, elemental composition and Optic analysis were performed by XRD, SEM, EDX, PL and optical transmission spectra. The XRD confirmed the formation of ZnS and CdS which revealed a broad spectrum in the low 2θ region due to its amorphous behaviour. The average optical transmission spectrum of ZnS lies between 65 % and 80 % and CdS lies between 50 and 60 %. The optical band gap of both the annealed films was decreasing with increase in temperature. The higher optical transmittance observed from emission spectra of PL analysis can contribute better performance and proved that the annealed ZnS and CdS thin films are applicable for photovoltaic applications. • CdS and ZnS nano thin films are prepared by Chemical Bath Deposition. • By increasing the annealing temperature, the optical band gap decreases. • The optical transmittance is higher for the films prepared and confirmed by Photoluminscence spectroscopy. • Both the nanofilms are recommended for photovoltaic applications. • The films are amorphous in nature and confirmed by XRD Spectroscopy. [ABSTRACT FROM AUTHOR]

Diving into the forefront of polymer light-emitting diodes (PLEDs), this study pioneers the synthesis of PEDOT:PSS-ZnS composite films on ITO surfaces, achieving remarkable advancements in charge transfer efficiency. Through meticulous optimization, these films exhibit extraordinary electrical conductivity (133 S/cm), specific capacitance (74.75 F/g), and hole mobility (132.56 cm 2 /Vs), supported by a finely tuned HOMO energy (−5.02 eV) and work function (5.02 eV). The resultant heightened optical conductivity promises unparallelled performance in the crucial role of hole transport layers (HTLs) within PLEDs. Further analysis unveils an impressive quantum efficiency (QE) of 28% and fluorescence resonance energy transfer (FRET) efficiency of 52%, underscoring the exceptional HTL characteristics. This breakthrough heralds PEDOT:PSS-ZnS composites as game-changers in crafting high-efficiency HTLs for PLEDs, seamlessly merging advanced optical, electrical, and electrochemical properties. The implications extend far beyond, illuminating a pathway towards transformative advancements in display and lighting technologies, destined to redefine the future of illumination. • This study focuses on the fabrication of PEDOT:PSS-ZnS composite films on an ITO surface, demonstrating their favourable charge transfer characteristics. • The optimized sample exhibited an electrical conductivity of 133 S/cm, along with a specific capacitance of 74.75 F/g. The hole mobility of the optimized PPZ13 is 132.56 cm2/Vs, HOMO energy of −5.02 eV with work function of 5.02 eV. • These findings suggest an increased optical conductivity, which can contribute to the efficient performance of the HTL in PLEDs. [ABSTRACT FROM AUTHOR]

The structural, morphological, and nano-mechanical properties of vacuum evaporated cadmium telluride (CdTe) and Zinc Sulfide (ZnS) films had been studied. The films used for the fabrication of optoelectronic sensors in the infrared range. The films had been deposited by vacuum evaporation technique on Si (100) substrate. The X-ray diffractogram had indicated stable polycrystalline cubic structure with (111) preferential orientation for both films. The crystallite size, intrinsic stress, microstrain, and dislocation density values had been evaluated to be 17.5 nm, 0.09 GPa, 9.96, and 3.2 × 1011 lines/cm2, respectively, for CdTe film. While for ZnS film, the parameters had been estimated to be 15 nm, 0.49 GPa, 9.71, and 4.4 × 1011 lines/cm2, respectively. The Field Emission Scanning Electron Microscopy (FESEM) study had revealed homogeneous, dense, and defect free structure of the film. Compositional analysis had confirmed that the Te/Cd ratio 1.1 while S/Zn ratio 0.71 in the grown films. Atomic Force Microscopy (AFM) measurements had indicated smooth and uniform film with rms surface roughness of ∼0.96 nm. Hardness, Young's modulus, strain rate, and creep of the top layer (ZnS) had been evaluated by nanoindentation. The hardness of the ZnS film had evaluated to be 1.80–2.39 GPa, and Young's modulus evaluated to be 181–248 GPa, for a 50–100 μN load. The outcome of the investigations endorsed the fact that the CdTe and ZnS thin films grown by the vacuum evaporation technique are suitable for the fabrication of optoelectronic devices. The Manuscript contains the detailed analysis of the following properties of the thin film. • Detailed analysis of structural parameters of thin films like crystallite size, microstrain, Intrinsic stress, defect density (dislocation density) • Morphology analysis indicating continuous and defect free film as well as elemental analysis (purity) of the film • Topography analysis for surface roughness and uniformity of thin film • Determination of mechanical properties of thin film like hardness, Young's modulus, creep and strain rate [ABSTRACT FROM AUTHOR]

Hydrothermal and thermolysis techniques were used to create ZnWO 4 and 0.9ZnWO 4 -0.1MS (M = Cd, Zn, Pb) samples. The formed phases in each sample and their structure and microstructure were examined using Raman spectroscopy, Fourier-transform infrared spectroscopy and Rietveld refinement of Synchrotron x-ray diffraction data. The composition and morphology of the formed samples were investigated via scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDS). The average crystallite size remains relatively constant regardless of the different metal chalcogenides. MS/ZnWO 4 samples have two distinct morphologies. The UV diffuse reflectance spectroscopy (UV-DRS) technique is used to investigate the linear and nonlinear optical parameters for different samples. Alloying ZnWO 4 with CdS or PbS affects the photo response region of the sample to include visible light. MS/ZnWO 4 (MS=CdS, ZnS, PbS) samples have optical band gap values of 2.56, 2.43, 2.99 and 3.1 eV, respectively. The CdS/ZnWO 4 and ZnS/ZnWO 4 samples exhibit the highest refractive index and optical dielectric constant values within the visible range. CdS or PbS/ZnWO 4 samples show the highest nonlinear optical parameters values within the visible range. The impact of MS samples on the photoluminescence emission of ZnWO 4 was explored. The CIE chromaticity diagram reveals that MS/ZnWO 4 (M = Zn and Pb) samples display a different degree of blue color while CdS/ZnWO 4 sample reveals green-yellow colors. • Raman spectra analysis confirmed the formation of CdS phase, nonexistence of the ZnS phase and could not detect PbS phase. • The values of n and k are influenced by the measured range of wavelengths and the type of alloying sample (MS) with ZnWO 4. • All samples exhibit a wide-ranging emission in the blue-green region. • The examined samples become more sensitive to daylight. [ABSTRACT FROM AUTHOR]

Ag NWs have received much attention from researchers due to their excellent optoelectronic properties and mechanical flexibility. However, the nano-size effect of Ag NW leads to their poor stability in harsh environments and easy oxidation, which makes it challenging to meet the application requirements of flexible electronic devices. Covering the surface of Ag NW with a protective layer coating is one of the most effective methods to address the stability of Ag NW. In this study, a ZnS protective layer is covered on the surface of Ag NW by utilizing a low-cost, simple, thickness-controllable, and densely packed hot vapor deposition film-forming method. The prepared ZnS/Ag NW network has low sheet resistance (9.7Ω/sq.) and high transmittance (86.6% at 550 nm). It maintains good oxidation resistance and thermal stability in various harsh environments. The ultrasonic test and adhesion test show good adhesion between the ZnS/Ag NW network and the PET substrate, and excellent mechanical stability and flexibility are demonstrated by bending test and fatigue test. • The prepared ZnS/Ag NW network has low sheet resistance (9.7Ω/sq.) and high transmittance (86.6% at 550 nm). It maintains good oxidation resistance and thermal stability in various harsh environments. • The ultrasonic test and adhesion test show good adhesion between the ZnS/Ag NW network and the PET substrate, and excellent mechanical stability and flexibility are demonstrated by the bending test and fatigue test. [ABSTRACT FROM AUTHOR]

We report the laboratory synthesis of Poly methyl methacrylate (PMMA)-Zinc sulfide (ZnS) nanocomposite via free radical polymerization method and its structural, optical, electrical, and dielectric properties for various concentration of ZnS nanoparticles. The formation of PMMA, ZnS and PMMA-ZnS nanocomposites was examined by X-ray diffraction technique, Fourier transforms infrared spectroscopy and FT-Raman spectrometer. Morphological structure of PMMA-ZnS nanocomposites showed the combination of pebbled and nanosphere like structure. The in-depth topological images were examined by transmission electron microscopy which indicated that the particles were fairly in good contact. The optimized and reduced band gap was calculated ∼3.30 eV. The photoluminescence spectra showed blue, green and yellow band with increased rate of e−-h+ recombination. The decay time of the PMMA-ZnS (5.0%) nanocomposite was ∼4.8413 ns, and the color purity was calculated ∼ 34.08%. The current density increased ∼249% which indicated the enhancement in conductivity. The dielectric properties of the PMMA-ZnS (5.0%) showed high dielectric constant with a very low dielectric loss. The reduction in optical band gap, high dielectric constant, and increased conductivity with increased in recombination rate confirmed that the as-prepared PMMA-ZnS nanocomposite can be used as an emissive layer in OLED devices. Image 1 • PMMA-ZnS nanocomposites were successfully synthesized via free radical polymerization method. • Optimum photoluminescence intensity was recorded for PMMA-ZnS (5.0%) nanocomposite. • Optimized band gap was recorded ∼3.30 eV and PMMA-ZnS nanocomposites showed blue shift. • Enhanced current density was calculated ∼110% as compared to ZnS. [ABSTRACT FROM AUTHOR]

In order to solve the difficulty of characterizing the optical constants of ZnS at high temperatures, the multi-phonon absorption dielectric function model which includes temperature parameters is constructed and modified in this paper. The multi-phonon absorption parameters of ZnS have been inverted based on variable temperature infrared transmittance spectra. The variable temperature infrared transmittance spectra of ZnS have been well fitted. The temperature dependence of the dissociation energy of ZnS materials is demonstrated, and the optical constants of the ZnS material have been obtained at 25 °C, 100 °C, 200 °C, 300 °C, and 400 °C. • The relationship between the value of m max and temperature is established in the multi-phonon absorption model of ZnS. • The ZnS multi-phonon parameters for various temperatures obtained by spectral inversion conform to physical laws. • Highly accurate variable-temperature optical constants of ZnS were obtained based on the multi-phonon absorption model. [ABSTRACT FROM AUTHOR]

Abstract A facile one-pot method to synthesis CuInS/ZnS (CIS/ZnS) QDs was developed. The prepared CIS/ZnS QDs exhibited a high bright emission. Moreover, the upconversion photoluminescence (PL) of the CIS/ZnS QDs was explored. Interestingly, extraordinary excitation-independent emission for both up and down conversion fluorescence of the CIS/ZnS QDs were observed. Analysis of X-ray diffraction (XRD) of CIS/ZnS QDs showed chalcopyrite crystal structure. The high-resolution transmission electron Microscopy (HRTEM) images demonstrated crystalline CIS/ZnS QDs with spherical shape and average diameter sizes of 2.5 nm and 3.6 nm for CIS core and CIS/ZnS QDs core shell, respectively. The selected area electron diffraction (SAED) suggested that the prepared CIS/ZnS QDs are polycrystalline with about 0.32 nm lattice distance. The PL peaks position was almost fixed and exhibited a strong peak at about 640 nm for both up and down conversion emission with a linear relationship between the intensity of the PL emission peaks and excitation wavelengths. Graphical abstract Schematic diagram showing downconversion and upconversion and subsequent the PL emission of CuInS/ZnS QDs with excitation wavelengths 450 and 800 nm respectively. Image 1 Highlights • Facile method to synthesis of colloidal CIS/ZnS QDs. • Up and down conversion features can be observed. • The PL peaks position is fixed and exhibited a strong peak at about 640 nm for both up and down conversion emission. • A linear relationship between the intensity of the PL and excitation wavelengths can be done in both up and down conversion process. [ABSTRACT FROM AUTHOR]

Highly photoactive merocyanine 540 is revealed to form charge transfer complex with zinc sulphide and cadmium sulphide nanocrystals confirmed by FT-IR Spectroscopy, Fluorescence emission and UV-Visible spectrophotometer. The semiconducting nanocrystals were synthesized by co-precipitation method and characterized by Fluorescence emission spectroscopy, UV-Visible spectroscopy, Scanning electron microscopy (SEM), X-ray spectroscopy and Energy dispersive X-ray spectroscopy (EDAX). Merocyanine, in different concentrations was chemisorbed on the surface of ZnS and CdS nanomaterial. ZnS and CdS nanoparticles were used in hybrid solar cells in combination with organic polymer. These cells performed good efficiency at (6 × 10 −6  M) dye concentration. The decreased power conversion efficiency with short circuit current density below and above the optimal merocyanine concentration (6 × 10 −6  M) may be due to aggregation of merocyanine dye on CdS nanocrystals and subsequent self-quenching phenomena among dye molecules. The power conversion efficiency of the devices fabricated from P3HT-CdS-MC540 was higher than devices fabricated from P3HT-ZnS-MC540 because of particle size effect. [ABSTRACT FROM AUTHOR]

Detailed characterization for double blended nanocomposite films of PVP (Polyvinylpyrrolidone)/CMC (carboxy-methyl cellulose) polymer blends doped with SnO 2 and ZnS nanoparticles based on different proportional concentrations (1-x)SnO 2 -x ZnS (x = 0, 0.25, 0.5, 0.75, 1) has been represented. Nanoparticles were synthesized based on the sol-gel technique, while nanocomposite films were prepared using the casting technique. The crystalline structures for both nanoparticles and nanocomposite films before and after laser exposure have been discussed by the x-ray technique. Fourier transform infrared spectroscopic technique (FTIR) revealed variations in the vibrational bands intensities and locations under the effect of both laser exposure and nanoparticles. The morphological features of the studied samples have been discussed through SEM (Scanning Electron Microscope) images. The optical properties (linear-nonlinear) of nanocomposite films have been discussed in details using UV–Vis spectroscopy technique. The refractive index has been calculated based on different proposed models. Similarities in the refractive index values have been observed. The effect of direct laser beam exposure on the estimated values of energy gap E g has been represented in details. E g values showed a reduction from 5.1 eV (for undoped films) to 4.8 eV (for laser exposed doped films). Nanocomposite films fully doped with 100% zinc sulphide nanoparticles exhibited the lowest E g value (4 eV). Linear and nonlinear optical parameters confirmed the dominant effect of direct laser exposure compared with the particle size effect. • Enhancement in the nanocomposite films features upon laser exposure. • Optical properties are clearly affected by the nanofillers particle size. • A dominant effect for the laser exposure on the nanocomposite blends compared with the particle size. • A promising variations in the optical parameters under the effect of 70 mJ/cm2 laser exposure. • All proposed models proved the domination effect of laser compared to nanofillers. [ABSTRACT FROM AUTHOR]

Zinc sulphide (ZnS) and transition metal-doped ZnS nanocrystals were synthesized by co-precipitation method. Further the synthesized nanocrystals were characterized by Field Emission Scanning Electron Microscope (FESEM), High Resolution Transmission Electron Microscope (HRTEM), Fluorescence, UV–Visible, X-ray diffraction (XRD) and Fourier Transformed Infra-red (FTIR) Spectrometer (FTIR). Scanning electron microscope supplemented with EDAX was employed to attain grain size and chemical composition of the nanomaterials. A considerable blue shift of absorption band was noted by the manganese concentration (0.5 M) in the doped sample in comparison with ZnS quantum dots because of the decrease in the size of nanoparticles which may be due to quantum confinement. The photoluminescence emission observed at 596 nm is due to the emission of divalent manganese and can be ascribed to a 4 T 1 → 6 A 1 transition within the 3d shell. Though, the broad blue emission band was observed at 424 nm which may originates from the radiative recombination comprising defect states in the un-doped zinc sulphide quantum dots. XRD analysis exhibited that the synthesized nanomaterial endured in cubic structure. The synthesized nanomaterial combined with organic polymer P3HT, poly (3-hexyl thiophene) and worked in the construction of inverted solar cells. The photovoltaic devices with un-doped zinc sulphide quantum dots showed power conversion efficiency of 0.48% without annealing and 0.52% with annealing. By doping with manganese, the efficiency was enhanced by a factor of 0.52 without annealing and 0.59 with annealing. The morphology and packing behavior of blend of nanocrystals with organic polymer were explored using Atomic Force Microscopy. [ABSTRACT FROM AUTHOR]

We investigate the photoluminescence, optical absorption and structural properties of ZnS submitted to laser irradiation in water and isopropyl alcohol. Nanoparticles were produced by irradiating micro-sized ZnS particles dispersed in both liquids, with and without the addition of Ag nanoparticles, taking advantage of the laser-assisted fragmentation effect. When ZnS microparticles are irradiated either in pure water or isopropyl alcohol a considerable size reduction is achieved (from micra to few nanometers). The photoluminescence of these nanoparticles mainly occurs in the UV, centered at 350 nm, and with smaller intensity in the visible, centered at 600 nm. Irradiation of ZnS microparticles dispersed in colloidal silver triggers a reaction between both materials, modifying its optical absorption and photoluminescent properties. After irradiation of ZnS in alcohol containing Ag nanoparticles, a giant increase of the UV photoluminescence is observed. Interestingly, when the irradiation is performed in aqueous Ag nanoparticles colloids, the photoluminescence suffers a red-shift towards the violet-blue. The data show that core-shell (Ag-ZnO) nanostructures are formed after irradiation and the visible emission likely originates from the ZnO shell grown around silver nanoparticles. The presence of Ag nanoparticles in the liquid medium promotes a stronger absorption of the laser beam during irradiation due to the coupling with the surface plasmon resonance, fostering intense reactions among ZnS, Ag nanoparticles, and the liquid medium. Our study shows that with a simple change of the liquid medium wherein the irradiation is conducted the photoluminescence can be tuned from UV to visible and core-shell nanostructures can be obtained. [ABSTRACT FROM AUTHOR]

Manganese (Mn) doping of ZnS phosphors was achieved by precipitation method using different ultrasound (US) maturation times. The structural and luminescence properties of the samples were carried out by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), photoluminescence (PL), and cathodoluminescence (CL). The real amount of manganese incorporated in ZnS lattice was calculated based on ICP-OES results. According with XRD patterns, the phase structure of ZnS:Mn samples is cubic. EDS spectra reveal deviations of the Mn dopant concentration from the target composition. Both 300 K PL and CL emission spectra of the Mn doped ZnS phosphors display intense orange emission at 590 and 600 nm, respectively, which is characteristic emission of Mn ion corresponding to a 4 T 1 → 6 A 1 transition. Both PL and CL spectra confirmed manganese is substitutionally incorporated into the ZnS host as Mn 2+ . However, it is suggested that the origin of broad blue emission around 400 nm appeared in CL is due to the radiative recombination at deep level defect states in the ZnS. The ultrasound treatment at first enhances the luminescent intensity by ∼3 times in comparison with samples prepared by classical way. This study gives rise to an optimization guideline, which is extremely demanded for the development of new luminescent materials. [ABSTRACT FROM AUTHOR]

Chemical vapor deposited (CVD) ZnS is a promising long-wave infrared (8–12 μm) window material. Yet antireflection is necessary since Fresnel reflection from its surface is high due to the high refractive index of ZnS. Sub-wavelength structured surface of micro hole array was fabricated on CVD ZnS by scanning ultrafast pulse laser ablation. The effects of beam profile, pulse width and beam power on the radius and morphology of the holes were studied. Gaussian beam can cause severe melted-resolidified layers around the hole, yet Bessel beam only resulted in thin ribbon around the hole. The picosecond Bessel laser is more suitable than femtosecond laser for ablating holes on ZnS. The radius of the holes increases with increasing the Bessel beam pulse width and the beam power. But larger power may cause circle grooves around the central holes. Ordered hole array was fabricated on single side of CVD ZnS and antireflection was realized. [ABSTRACT FROM AUTHOR]

Porous ZnS/MXene Ti 3 C 2 nanocomposite was synthesized by one-step hydrothermal method. MXene Ti 3 C 2 with a unique layered structure was used as cocatalyst. ZnS/MXene Ti 3 C 2 nanocomposite was utilized for photocatalytic degradation of tetracycline hydrochloride (TCH). The photodegradation efficiency of TCH were 96% during 60 min under simulated sunlight irradiation. The opened 2D space of MXene Ti 3 C 2 was suitable for ZnS nanoparticles dispersion, which obtained a mesoporous nanocomposite with plenty of heterostructure interfaces. At the same time, the good electron transfer efficiency of MXene Ti 3 C 2 could also provide the high-speed channel through the numerous intimate heterostructure interfaces. Meanwhile, ZnS/MXene Ti 3 C 2 nanocomposite could still maintain a good stability after three cycles. It was significant that ZnS/MXene Ti 3 C 2 nanocomposite achieved an excellent separation efficiency of photogenerated carriers via constructing heterojunction. It proved that porous ZnS/MXene Ti 3 C 2 nanocomposite as a mesoporous superior photocatalyst was an effective and potential photocatalyst for antibiotic degradation. The opened 2D space of MXene Ti 3 C 2 was suitable for ZnS nanoparticles dispersion, which obtained a mesoporous nanocomposite with plenty of heterostructure interfaces. ZnS/MXene Ti 3 C 2 nanocomposite had a terrific photocatalytic capacity for photodegradation tetracycline hydrochloride. [Display omitted] • Porous ZnS/MXene Ti 3 C 2 nanocomposite was synthesized by one-pot hydrothermal method. • ZnS/MXene Ti 3 C 2 nanocomposite attained a fast photogenerated electron transfer path via numerous heterostructure interfaces. • Porous ZnS/MXene Ti 3 C 2 nanocomposite had a terrific photocatalytic capacity for photodegradation tetracycline hydrochloride. [ABSTRACT FROM AUTHOR]

The work investigates the incorporation of Eu 3+ ion in ZnS crystal through spectroscopic studies. ZnS: Eu 3+ nanocrystals was synthesized via the precipitation technique. Elemental composition analysis indicates a non-stoichiometric distribution between Zn and S. X-ray diffraction studies show lattice expansion demonstrating that Eu 3+ ions were incorporated in the host lattice. Annealing temperature gave rise to lattice contraction relative to the as-synthesized indicating a partial expulsion of the ion from the crystal due to heat treatment. Eu 3+ ions site symmetry probing from optical features show that trivalent europium were situated both at the nanocrystals surface and at the Zn 2+ ion site. Weak energy transfer from host to activator ion occurred probably mainly through exchange interaction and the transfer process was defect mediated. [ABSTRACT FROM AUTHOR]

In the present work, we have deposited indium-doped zinc sulfide (ZnS:In) thin films by chemical bath deposition technique (CBD). The structural properties studied by X-ray diffraction indicate that ZnS:In has a cubic structure with an average crystallite size 4.7–11.0 nm. Transmission and reflection spectra reveal the presence of interference fringes indicating thickness uniformity and surface homogeneity of deposited material. All the films were transparent in the visible and infrared regions (⩾60%), which allows us to use this material as an optical window or a buffer layer in solar cells. The obtained band gap energy E g is in the range of 3.70–3.76 eV. The refractive index and thickness of ZnS:In thin films was calculated using envelope method. The variation of the refractive index along the Cauchy distribution was observed in all ZnS:In thin films. The analysis of the refractive index data through the Wemple–DiDomenico model leads to the single oscillator energy ( E 0 ) and the dispersion energy ( E d ). [ABSTRACT FROM AUTHOR]

The present study deals with the structural, optical and photocatalytic studies of thioglycerol capped doped ZnS nanoparticles (NPs). Effect of two dopant metal ions (Ni and Mn) on photoluminescence emission and photocatalytic properties have been studied in detail. Zn 1− x M x S; M = Ni or Mn; x = 0, 0.01, 0.02, 0.03 and 0.04 NPs have been synthesized using simple chemical precipitation route. Structural and morphological studies have been done by using X-ray diffraction (XRD) technique and high resolution transmission electron microscopy (HRTEM). Capping of thioglycerol on the surface of doped ZnS has been confirmed by Fourier transform infrared (FTIR) studies. UV–Vis and photoluminescence studies have been carried out to study the effect of doping on optical properties of synthesized materials. Degradation of crystal violet has been carried out with the aim to investigate the effect of Ni or Mn doping on photocatalytic activity of ZnS. It has been observed that both the metal ions have decreased the photocatalytic activity of ZnS. The effect of photocatalytic reaction temperature on photocatalytic properties of one of the doped sample has also been investigated. It has been interpreted from the results that photocatalytic activity of doped semiconductor nanostructures is strongly dependant on their photoluminescence properties as well as on photocatalytic reaction temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZnS:X− (X=F and I) nanoparticles were synthesized by a solid state reaction. [•] Emission of ZnS nanoparticles was increased remarkably by doping F and I. [•] Luminescence of ZnS:F− nanoparticles was more intense than that of ZnS:I−. [Copyright &y& Elsevier]

Highlights: [•] The luminescence intensity of Mn2+ in ZnS:Mn,Eu is highly dependent on Eu2+. [•] The luminescence enhancement of Mn2+ by Eu2+ is as high as 5.5 times. [•] The X-ray luminescence enhancement is by a factor of 2.5. [•] There is energy transfer from Eu2+-related defects to Mn2+ in ZnS:Mn,Eu. [•] Energy transfer and phonon modification are responsible for the enhancement. [Copyright &y& Elsevier]

Abstract: Antireflective sub-wavelength structures (SWSs) combined a Ge1− x C x coating on Zinc sulfide (ZnS) can enhance the long-wave infrared transmission and durability of ZnS, which have the potent for practical applications. We have investigated the antireflective characteristics of Ge1− x C x sub-wavelength periodic hole structures on ZnS through the Fourier modal method (FMM) for application with normally incident, randomly polarized, 10.6μm wavelength. Then according to the results, we have successfully fabricated the sub-wavelength periodic square hole structures with Ge0.05C0.95 films on one side of ZnS. A substantial transmittance improvement for bare ZnS in the 8–12μm spectral region was obtained. [Copyright &y& Elsevier]

Abstract: ZnS quantum dots of size ∼3nm are prepared at 303K using ZnSO4 and Na2S2O3 precursors with thioglycerol as stabilizing agent. Cd2+ doped ZnS were prepared by varying doping concentration from 1 to 8 wt.%. ZnS quantum dots were mixed with CdS quantum dots of size ∼4nm in the 3:1, 2:1, 1:1, 1:2, 1:3 and 1:4M ratio. The nanoparticles were characterized by UV–vis, photoluminescence (PL), XRD and high-resolution TEM measurements. The XRD pattern, high-resolution TEM image and SAED pattern reveal that the nanoparticles are in well-crystallized cubic phase. The band gap of ZnS has increased from the bulk value 3.7 to 4.11eV showing quantum size effect. Excitonic transition is observed at 274nm in UV absorption and PL emission at 411nm. Doping with Cd2+ red-shifts both UV and PL spectral bands and enhances the PL band of ZnS nanoparticles. Mixing CdS and ZnS quantum dots in different molar ratios shows red-shift of the band edge in the CdS/ZnS hybrid system. In the 1:1 hybrid system of CdS/ZnS nanoparticles, PL band is red-shifted and the intensity is almost doubled with respect to that of CdS nanoparticles. [Copyright &y& Elsevier]

Abstract: ZnS nanocrystals (NCs) capped with tetramethylammonium (TMAH) were synthesized from ZnCl2 ·2H2O and thiourea using a wet chemical process. Further treatments of the nanocrystals such as aging, and annealing have been conducted to examine the stability of the grown samples. The X-ray diffraction spectra show that the crystal has a zinc blende structure with particle size of about 2nm. The evidence of nanocrystalline character is also clear in the UV–Vis absorption that shows an excitonic peak at about 236nm (5.2eV) arising from band edge transitions. A photoluminescence emission peak centered at about 450nm (2.7eV) is attributed to transitions between shallow donors and Zn+ vacancies. Both absorption and photoluminescence spectra show that sample aging does not affect the characteristics of the sample, possibly due to protection by TMAH capping. Annealing at 700°C and 900°C results in the red shift of the photoluminescence. [Copyright &y& Elsevier]

ZnS nanocrystallites doped with organic dye (molecular chromophore) have been synthesized using a simple chemical method. Composite ZnS nanoparticles having different sizes and morphology can be obtained. The size of these composite nanoparticles is typically 10–30 nm. A dramatic increase in the luminescence intensity and a change in the emission wavelength have been observed from the composite nanoparticles. Because of the different structure and properties of dyes, the absorption, excitation and emission spectra of the composite nanoparticles vary with different dyes. [Copyright &y& Elsevier]

ZnS nanoparticles doped with Ni2+ and Mn2+ have been prepared by co-precipitation from homogeneous solutions of Zn, Ni and Mn salt compounds, with S2− as precipitating anion formed by decomposition of thioacetamide (TAA). X-ray diffraction analysis shows that the average crystalline particle size of the doped and undoped ZnS nanometer scale samples is about 2–4 nm. A novel luminescent property has been observed in the photoluminescence (PL) spectra of the ZnS nanoparticles co-doped with Ni2+ and Mn2+. The ZnS nanoparticles can be doped with Ni2+ and Mn2+ during synthesis without altering the X-ray diffraction pattern. However, the emission wavelengths (with a color range from blue to green, λem=475–540 nm) and PL intensities of the co-doped samples vary with changing the impurity mole ratios of Ni2+ and Mn2+ in the co-doped samples. When the mole ratios of Ni2+ and Mn2+ in the co-doped sample are 0.3% and 2.0%, respectively, the relative fluorescence intensity of the co-doped samples is about four times of that of un-doped ZnS nanocrystals. The PL properties of the co-doped samples are dramatically different from those of Ni2+- and Mn2+-doped ZnS nanocrystals. [Copyright &y& Elsevier]

In this work, we present the fabrication of heterojunction Cu 2 SnS 3 /ZnS photovoltaic cell using indigenously developed cost-effective ultrasonic spray pyrolysis method. Substrate temperature of as-prepared films have been varied from 350 °C to 500 °C. Temperature played a key role in enhancing the optical properties of ZnS films making it useable as window layer for solar cell. The p-type Cu 2 SnS 3 (CTS) absorber layer of the cell is grown at optimized substrate temperature (500 °C) and with optimized Cu and Sn composition. Finally, solar cell is fabricated with these optimized p and n layers and have the structure of glass/FTO/Cu 2 SnS 3 /ZnS/Ag with V oc = 685 mV, J SC = 1.8 mA/cm2, fill factor = 39% and solar efficiency = 0.5%. A detailed discussion is given in overcoming the intricacies involved in the cell and improving the efficiency. [Display omitted] • A low-cost single step deposition of earth abundant window layer ZnS films. • Substrate temperature is optimized for better transmittance of ZnS films. • ZnS exhibited n type conductivity which is essential to form the PN junction for solar cell application. • Solar cell has been fabricated using low cost indigenously developed using ultrasonic spray pyrolysis techniques. [ABSTRACT FROM AUTHOR]

ZnS thin films were deposited on both soda-lime glass and p–Si substrates by radio frequency (RF) sputtering of a single ZnS target. The morphological, structural, and optical properties of the films were analyzed. It was seen that the thin films had (111) and (200) orientations of ZnS structure. The particle size distribution of the SEM image showed that the ZnS thin film had a 44.00 ± 0.56 nm average particle size. The optical band gap of ZnS thin films was calculated as 3.7 eV using UV–vis data. The electrical and photoelectrical properties of an Ag/ZnS/p–Si heterojunction were analyzed using current–voltage (I–V) and capacitance–voltage (C–V) measurements. The results showed that the device had 0.694 eV barrier height and 449 Ω series resistance values. In addition, the photodiode of the device was analyzed by I–V measurements under a solar simulator with AM1.5 global filter. Finally, the barrier height value obtained from C–V measurements was compatible with the I–V method. • Deposition of ZnS thin films by magnetron sputtering of single target. • Determination of the average particle size of the film by Gaussian distribution. • Execution of electrical and photoelectrical properties of Ag/ZnS/p-Si structure. • Report of photodiode behavior of Ag/ZnS/p-Si structure. [ABSTRACT FROM AUTHOR]

Albumin as a globular protein plays a substantial role in the preserving plasma pressure and the nutritional balance and consequently the albumin level serves as an indicator of liver health and function. In this work a simple synthetic method of highly photoluminescent (PL) Mn x 2 + Zn 2 − x S (0 ≤ x ≤ 0.1) doped quantum dots (QDs) were synthesized by the wet chemical method and capped with 3-mercaptopropionic acid (MPA). The prepared Mn doped ZnS QDs and the pristine ZnS QDs were characterized by fluorescent emission spectra, X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). The pristine ZnS QDs showed a relatively weak emission PL Gaussian peak at about 395 nm while Mn doped ZnS QDs illustrated dual emission peaks at 425 and 570 nm. HRTEM images appeared cubic nanocrystals for ZnS and Mn 0.04 2 + Zn 1.96 S QDs with average particle sizes of 13 and 16 nm, respectively. The prepared Mn- doped ZnS QDs were applied as an optical sensor for determination of bovine serum albumin (BSA) in aqueous solutions. The QDs sensor exhibited a linear working range from 0.1 to 0.95 μM of albumin with R2 = 0.984. The limit of detection (LOD) of this system was found to be 1.56 × 10−7 M. This method is not only simple, sensitive and low cost, but also reliable for practical applications. Solution-processed ZnS QDs was used for the real time, label free optical detection of BSA. • The prepared Mn2+ doped ZnS QDs were applied as an optical sensor for determination of BSA in aqueous solutions. • Novel synthetic method of Mn2+ doped ZnS QDs quantum dots based on wet chemical method and capped with MPA. • Characterize the fabricated BSA sensor based on fluorescent emission spectra, XRD, HTEM. • BSA sensor investigate a PL peak with linear working range from 0.1 to 0.95 μM, R2 = 0.984 minimum LOD of 1.56 × 10-7 M. [ABSTRACT FROM AUTHOR]

Solar photovoltaic cell research is always fascinating due to its clean, green nature. Cu 2 ZnSnS4Se 4 (CZTSSe)-based solar cells show fruitful performance in the field of power generation models based on sunlight. To improve the efficiency of CZTSSe-based solar cells, overall optimization remains an obstacle. Both thickness and bandgap of the absorber layer and the buffer layer have been optimized. Additionally, the contour plot of thickness vs. bandgap and bandgap vs. bandgap are further analyzed for overall optimization. Using the optimal values of the buffer layer based CZTSSe solar photovoltaic cell the efficiency has been observed as 24.8%. This earth's abundant, non-toxic buffer layer of CZTSSe solar photovoltaic cells could prove to be highly efficient CZTSSe based solar photovoltaic cells experimentally in the future. This earth's abundant, non-toxic buffer layer of CZTSSe solar photovoltaic cells could prove to be highly efficient CZTSSe solar cells experimentally in the future. Image 1 • Maximum efficiency of CZTSSe solar cell has been obtained as 24.8%. • This earth's abundant, non-toxic buffer layer (ZnS) is used. • Current (I s) rises lead to decreases the V oc due to temperature sensitive. • Both thickness and bandgap of the CZTSSe and ZnS have been optimized. [ABSTRACT FROM AUTHOR]

In this work, manganese doped zinc sulfide (ZnS: Mn2+) samples were synthesized by a solid-state method under various sintering temperature. With the increase of temperature, ZnS: Mn2+ was gradually evolved from zinc blende to wurtzite phase with particle size reduced. Further increasing the sintering temperature of wurtzite ZnS: Mn2+ could lead to a preferred orientation of crystal phase. The above physical structure evolutions aroused remarkably changes on the luminescent properties of ZnS: Mn2+, and the effects of sintering temperature and phase transition were investigated. The results suggested that ZnS: Mn2+ of wurtzite phase was more efficient for both photoluminescence and triboluminescence. This should be attributed to not only the enhanced excitation efficiency and piezoelectricity, but also the increased carrier density in traps and the beneficial kinetic order of ZnS: Mn2+ in wurtzite phase. The photoluminescence and triboluminescence of ZnS: Mn2+ showed different spectral shift behaviors along with the crystal phase variation, suggesting that they possessed different energy transfer pathways and thus the distinct dependence on crystal field and band gap. The presented research on the luminescent behaviors of ZnS: Mn2+ with varied crystal phase, especially for the content regarding to triboluminescence, should be useful to further guide the design and optimization of ZnS-based luminescent materials as well as the full reveal of its luminescent mechanisms. • Manganese doped zinc sulfide was synthesized under different sintering temperature. • The wurtzite structure was more efficient for both PL and TL. • The PL and TL showed different crystal phase effects on the spectral shift. [ABSTRACT FROM AUTHOR]

Antimony sulfide (Sb 2 S 3) solar cell is considered to be an emerging photovoltaic device technology. However, the conversion efficiency of Sb 2 S 3 solar cell remains limited to lower than 8%. To boost the conversion efficiency, a device structure consists of FTO/ZnS/Sb 2 S 3 /Cu 2 O/Au was proposed and the device photovoltaic performance has been numerical simulated by wxAMPS. The initial values of bulk defect density in Sb 2 S 3 layer and interface defect density at ZnS/Sb 2 S 3 and Sb 2 S 3 /Cu 2 O interfaces are set to be 1016 cm−3, 1010 cm−2 and 1010 cm−2, respectively. The conversion efficiency increases from 6.24% to 16.65% by incorporating a Cu 2 O layer into the solar cell. The influence of Sb 2 S 3 bulk material quality on device photovoltaic performance was also analyzed. It is important to note that a proper higher carrier diffusion length than the thickness of Sb 2 S 3 layer should be guaranteed to facilitate the conversion of photogenerated electron-hole pairs to photogenerated current. It is feasible to achieve a value of 1015 cm−3 for bulk defect density in Sb 2 S 3 layer (corresponding diffusion length is calculated to 1.6 μm) in further experimental work, then the optimized conversion efficiency of 21.99% at an optimized Sb 2 S 3 layer thickness of 0.8 μm could be arrived. Furthermore, the influence of interface defects at ZnS/Sb 2 S 3 and Sb 2 S 3 /Cu 2 O interfaces on device photovoltaic performance were also analyzed. It is feasible to achieve a value of 109 cm−2 for interface defect density at ZnS/Sb 2 S 3 and Sb 2 S 3 /Cu 2 O interfaces and a best conversion efficiency of 22.78% can be obtained. • High photovoltaics performance Sb 2 S 3 solar cell has been achieved using Cu 2 O hole transport layer. • A solar cell with a structure of FTO/ZnS/Sb 2 Se 3 /Cu 2 O/Au can achieve an efficiency as high as 22.78%. • The effects of physical parameters on the device photovoltaics performance parameters have been studied. [ABSTRACT FROM AUTHOR]