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In the era of Photonics, design and development of novel rare earth ion-doped quantum dots (QDs) for optoelectronic applications has gained significant interest owing to their outstanding characteristics. Simultaneously, the creation of a new class of photocatalytic materials on the nanoscale is also imperative for environmental purification. Thus, we report on wet chemical synthesis, the structural, morphological, and optical characteristics, fluorescence, and hydrogen evolution of ZnS:Eu (0, 2, 4, and 6 at%) QDs for optoelectronic and photocatalytic applications. Comprehensive structural studies depicted that Eu3+ ions were efficiently substituted into the host matrix and altered the original structure of the ZnS compound. The emission spectra of the ZnS:Eu QDs exhibited distinctive red fluorescence owing to the transition of dopant ions in 5D0 - 7F1, 5D0 - 7F2, 5D0 - 7F3, and 5D0 - 7F4 energy levels of the 4f orbital of the Eu3+ ions. Moreover, the photocatalytic properties of ZnS:Eu (6 at%) QDs possess better catalytic efficiency toward hydrogen evolution through a water splitting mechanism under simulated sunlight irradiation. The observed photocatalytic phenomenon in the synthesized samples agreed well with the luminescence properties exhibited by the QDs.

In the present study, we fabricate the ZnS: V (0, 2, 4, and 6 at%) nanoparticles (NPs) using the chemical-refluxing technique. We analyzed these samples based on structural, optical, magnetic, degradation, and hydrogen evolution properties. Comprehensive analyses of the chemical, structural, and optical measurements show that the vanadium (V) ions occupied the Zn host site without altering their original structure and without forming new phases. We confirmed the paramagnetic nature of the doped samples via magnetic measurements. We examined the photocatalytic properties of the fabricated NPs by the degrading Rhodamine-B (RhB) dye in an aqueous solution under the ultraviolet (UV) light, and the ZnS: V of 2 at% displayed higher degradation efficiency than the other samples. Moreover, 2 at% ZnS: V (sample showed a higher H2 evolution rate (1140 μmolg−1h−1) than the other samples and was 17 times greater than that of pure ZnS lattice. The observed efficient photocatalytic organic pollutant degradation and better hydrogen fuel evolution in 2 at% ZnS: V sample could be due to the presence of a large surface area, creation of more defect sites, dislocation sites of the prepared compound, generation, and the presence of a huge number of charge carriers due to the substitution of V-dopant in the Zn host site and non-recombination rate of charges.

The design and production of co-doped diluted magnetic semiconductor nanostructures for the development of spin-related operating electronic devices have gained considerable attention owing to their formidable characteristics. In this study, we strived to fabricate ZnO, Zn0.98Ni0.02O, Zn0.97Ni0.02Er0.01O, and Zn0.96Ni0.02Er0.02O nanoparticles. The successful penetration of Ni and Er ions into the ZnO host material was confirmed through wide-ranging structural analyses. A slight change in the bandgap of ZnO was obtained by doping and co-doping. The photoluminescence spectra revealed that doping and co-doping induced various emissions as well as structural defects in the fabricated nanoparticles. Magnetic hysteresis loops revealed that the ZnO and Zn0.98Ni0.02O nanoparticles possessed a paramagnetic nature. However, the Zn0.97Ni0.02Er0.01O and Zn0.96Ni0.02Er0.02O nanoparticles exhibited robust ferromagnetism with clear hysteresis loops. Bound magnetic polaron behavior is well-anticipated to describe the ferromagnetism in the synthesized nanoparticles. Hence, (Ni + Er) co-doping is a promising approach for extending the ferromagnetic nature of the ZnO system for spin-based electronic devices.

Diluted magnetic semiconductors related to II–VI-based compounds are of significant interest for the development of spin-based operating electronic devices such as magneto-optical instruments, spintronics, and nonvolatile memory devices. Thus, studies of electron paramagnetic resonance, magnetic characteristics, and the photocatalytic properties of transition metal-doped II–VI-based semiconductors are of great importance. We therefore comprehensively studied the structural, electron spin resonance, magnetic hysteresis, and photocatalytic characteristics of CdS:V4+ nanoparticles (NPs) fabricated by the rapid microwave route for the first time. The structural analyses revealed the authentic substitution of V4+ dopant ions into the CdS matrix. The widening of the optical band gap and relevant quantum confinement phenomenon are discussed in terms of the inclusion of V4+ ions into the CdS matrix. The electron paramagnetic resonance (EPR) spectroscopy results were corroborated by the increase in the number of magnetic spins with increasing V4+ dopant concentration. The assessed number of magnetic spins was nearly equal to 3.601597 × 106 and 7.254048 × 106 for the CdS:V (2 and 4 at%) NPs, respectively. Room-temperature magnetic hysteresis loops also revealed the existence of a large number of magnetic spins through the formation of clear paramagnetism in the CdS:V (2 and 4 at%) NPs. The CdS:V (4 at%) system displayed enriched visible light-driven photocatalytic degradation efficiency compared to bare CdS through the degradation of RhB dye in contaminated water.

Generation of hydrogen fuel via the photocatalytic water splitting mechanism using semiconductor nanoparticles under sunlight irradiation is highly important. Moreover, the development of nanophotocatalysts for polluted water treatment is significant. In this regard, we synthesized CdS, CdS:Er (2 at%), and CdS:Er (4 at%) nanoparticles by a simple reflux route. According to the comprehensive structural analysis, Er3+ ions were incorporated into the CdS host lattice at the substitutional and interstitial sites, without altering the original structure. Photocatalytic measurements revealed that the degradation efficiency of 2 at% Er-doped CdS nanoparticles reached 100% within 100 min of visible light irradiation. In addition, CdS:Er (2 at%) nanoparticles exhibited enhanced photocatalytic hydrogen generation ability under simulated sunlight irradiation. Hence, from the obtained results, we concluded that CdS:Er (2 at%) nanoparticles are promising semiconductor photocatalytic materials for wastewater treatment as well as hydrogen fuel generation.

Design and development of novel highly efficient diluted magnetic semiconductors for spintronic devices and photocatalytic application is of great importance. In this regard, we report on the synthesis and analysis of new class of highly efficient pure CeO2, Ce0.42Fe0.04Co0.04O50, Ce0.42Co0.04Ni0.04O50 and Ce0.38Fe0.04Co0.04Ni0.04O50 nanoparticles. The crystal structure, phase, optical characteristics, magnetic properties and photocatalytic characteristics of synthesized nanoparticles were measured using various analytical techniques. The comprehensive structural analyses revealed that incorporation of Fe, Co and Ni ions in host lattice without change their original structure. Presence of defect sites in synthesized nanoparticles was confirmed through photoluminescence studies. Room temperature magnetic measurements revealed that pure CeO2 and Ce0.42Fe0.04Co0.04O50 nanoparticles showed paramagnetic nature as well as Ce0.42Co0.04Ni0.04O50 and Ce0.38Fe0.04Co0.04Ni0.04O50 nanoparticles exhibited mixed behavior of paramagnetic and ferromagnetic characteristics. Further, Ce0.38Fe0.04Co0.04Ni0.04O50 nanoparticles showed better photocatalytic activity with pseudo first order rate constant 0.0157 (min−1) and it is 1.7 times larger than that of pristine CeO2 nanoparticles.

The design and development of one-dimensional nanostructures have been gaining considerable interest owing to the exceptional optoelectronic and catalytic properties of these structures. Thus, herein, wurtzite phase polycrystalline one-dimensional nanostructures of pristine and Co-substituted ZnO nanorods were fabricated using the hydrothermal method. Co ion substitution into the ZnO lattice was confirmed by structural analysis. Furthermore, an X-ray photoelectron spectroscopic survey suggested that Co ion inclusion in the host Zn2+ site occurred with a Co2+ oxidization state. The quenching of band gap with the Co inclusion into ZnO host sites was determined through optical studies. Room temperature hysteresis curves demonstrated the superparamagnetic nature of the synthesized ZnO and Co-doped ZnO nanorods. The photocatalytic activity of the synthesized nanorods was estimated by the exclusion of Rhodamine-B degradation under artificial solar light illumination. Distinctly, 66.5% photocatalytic degradation efficiency was achieved in Co-doped ZnO nanorods over 100 min; however, only 64.13% efficiency was observed for bare ZnO nanorods over 120 min. The enhanced photocatalytic activity in the Co-doped ZnO sample could be due to the creation of huge trapping sites, massive surface area, and generation and consequent separation of electron and hole pairs.

We report the fabrication of CdS:Nd nanoparticles (NPs) via an economical co-precipitation method, giving adjustable optical, magnetic and photocatalytic behavior of the nanocrystalline CdS by varying the Nd ion doping concentration. The sensible doping of Nd ions into the CdS matrix was confirmed by various structural characterization techniques. Transmission electron microscopy images demonstrated the basic spheroid shape of the nanoparticles, with sizes in the range of 8–10 nm. A doping concentration-dependent redshift was observed in the CdS NP spectra, resulting from the decrease in the bandgap. The M-H curves illustrate that the undoped sample is diamagnetic, the 2 at% Nd sample is ferromagnetic, and the 4 at% Nd sample is superparamagnetic at room temperature. Photocatalytic measurements revealed that the CdS:Nd (4 at%) sample displayed better photocatalytic activity than undoped CdS NPs. As per literature, this could be the first report on the CdS:Nd system and we believed that it will be more beneficial for the further research on the CdS:Nd system.

Magnetically polarized semiconductors are of significant interest in view of their application in spintronic devices. In this study, the microstructure and room temperature ferromagnetic characteristics of ZnO, Zn0.48Tb0.02O50, and Zn0.47Tb0.02Cu0.01O50 nanoparticles (NPs) have been reported. The crystal structure and grain size of the samples were elucidated from comprehensive structural analyses; the results revealed a wurtzite crystal structure with dopant and co-dopant ions located at substitutional or interstitial sites in the ZnO host lattice. The nanoparticles sizes estimated from X-ray diffraction were confirmed by transmission electron microscopy. Diffuse reflectance spectra and the corresponding Kubelka-Munk plots suggested band gap quenching due to the inclusion of dopant ions. Magnetic measurements revealed diamagnetic character for the bare host material, while Zn0.48Tb0.02O50 and Zn0.47Tb0.02Cu0.01O50 showed bending of hysteresis loops in the low magnetic field region and linear behavior within a certain range at higher fields, indicating ferromagnetic and paramagnetic behavior in the two regimes.

CdS, Cd0.98Gd0.02S, and Cd0.96Gd0.04S quantum dots (QDs) have been fabricated by solvothermal method and found to form in cubic phase. Raman spectra displayed first as well as second order longitudinal modes of CdS QDs. Transmission electron microscopy images depict the nearly spheroid particles of size in the range of 3.8–6.2 nm. Reflectance spectra showed that the absorption edge of the Cd0.98Gd0.02S and Cd0.96Gd0.04S QDs was red-shifted compared to that of CdS QDs. Electron paramagnetic resonance spectra of Cd0.98Gd0.02S and Cd0.96Gd0.04S reveal resonance signals at g ≈ 2.16 and 2.93 corresponding to the gadolinium (III) ions located at sites with frail as well as intermediate crystal field. Exploration of the magnetic property reveals that the Cd0.98Gd0.02S and Cd0.96Gd0.04S QDs show signs of superparamagnetism. The photocatalytic activity of CdS and Cd0.96Gd0.04S QDs was studied on malachite green oxalate dye under artificial solar light irradiation. The decomposition rate of CdS and Cd0.96Gd0.04S QDs evaluated on the malachite green oxalate dye is as follows: Cd0.96Gd0.04S > CdS.

Pristine and Co-doped ZnS quantum dots (QDs) were fabricated via a hydrothermal technique. Morphology studies showed that the fabricated QDs were nearly spheroidal with narrow size distribution. X-ray diffraction and Raman spectroscopy analyses demonstrated that the Co ions effectively penetrated the host matrix without changing its cubic phase. A minimal blue shift was found in the pristine ZnS QDs after doping with Co. The pristine and Co-doped samples exhibited similar blue emission, while increased (two times) photoluminescence intensity was observed for the Co-doped sample. X-ray photoelectron spectroscopy analysis showed trivalent Co ions in the ZnS lattice. The diamagnetic ZnS QDs were turned into ferromagnetic through Co-doping. The Co-doped ZnS QDs portrayed higher photocatalytic degradation (PCD) of Rhodamine B dye under artificial solar simulator irradiation than pristine ZnS. Hence, the Co-doped ZnS QDs may find applications in luminescent, spintronic and photocatalytic devices.

CdS and CdS:Eu quantum dots (QDs) with relatively uniform size and a narrow size distribution were fabricated by a solvothermal method. X-ray diffraction and Raman spectroscopy analyses revealed that the synthesized samples were polycrystalline with a cubic structure. An almost spheroidal morphology with slight polydispersity was observed in both low and high-resolution transmission electron microscopy images. The optical band gap of the CdS and CdS:Eu QDs was found to be 3.1–3.3 eV. An X-ray photoelectron spectroscopy analysis disclosed the existence of Eu with a trivalent state and the obtained composition values are nearer to stoichiometry. The CdS:Eu QDs displayed room-temperature ferromagnetism. The CdS:Eu QDs showed enhanced photocatalytic activity compared to CdS during malachite green oxalate dye degradation under artificial solar illumination. Hence, Eu doping is a promising path for facilitating better photocatalytic activity and ferromagnetism of CdS.

Zinc Sulfide (ZnS) quantum dots (QDs) with enhanced fluorescence efficiency and photocatalytic activity have been attained through Ga doping for the first time. Ga-doped ZnS QDs were synthesized via a solvothermal method using Polyethylene glycol (PEG) as a stabilizer. Transmission electron microscopy studies disclosed that the obtained QDs were slightly polydispersed with an average size of 5.5–3.8 nm. The results of X-ray diffraction and Raman and X-ray photoelectron spectroscopy stipulated that the Ga ions were successfully incorporated into the ZnS crystal lattice without amending their internal structure. A blue shift was noticed in the ZnS QDs when doped with Ga. The photoluminescence spectra of all the QDs displayed the same blue emission and enhanced fluorescence efficiency with increase in Ga doping content. The photocatalytic degradation of the phenol red dye under UV-light illumination was enhanced with increasing Ga doping concentration. Thus, the Ga-doped ZnS QDs are potential and favorable candidates for both photoluminescent and photocatalytic device applications.

A semiconductor compound, which portrays ferromagnetism with tunable optical and photoluminescence properties after a sensible doping of suitable dopant, is vital for modern spintronic and luminescent applications. In this sense, we fabricate CdS, Cd0.98Er0.02S, and Cd0.96Er0.04S nanoparticles (NPs) via an inexpensive co-precipitation way. No structural deformation was found in cubic CdS after Er (III) doping. The as-fabricated NPs demonstrated good crystallinity as well as slight changes in sizes varying 3 nm–7 nm. An X-ray photoelectron spectroscopy results confirmed that the impure-free nature of the prepared samples. A decreasing trend in the optical band gap was found by the increase in the doping level. The 1CdS NPs showed diamagnetic character, whereas the Er (III)-doped CdS NPs exhibited frail ferromagnetic character at room temperature, which slightly increased as a function of Er (III) concentration. Based on the literature, this is the initial magnetic report on the CdS:Er system and this will be very informative for the further magnetic investigations on the Er doping. Hence, the tunable optical and ferromagnetic magnetic properties of CdS:Er NPs demonstrated in this work may be beneficial for optoelectronic, solar cell and spintronic applications.

In the present report, we represent on synthesis of pristine ZnO and ZnO:Ga nanorods by a simple and economical hydrothermal method. Comprehensive structural analyses revealed that the Ga dopant ions were effectively penetrated the ZnO parent matrix. Morphological analysis illustrated that the synthesized samples belonged to one-dimensional nanostructures such as nanorods. Optical studies revealed the substitution of the Ga dopant into the host lattice and reduction of the optical bandgap. Enhanced luminescence characteristics were observed in the pristine ZnO nanorods through photoluminescence spectroscopic analysis. Magnetic hysteresis loops indicated that both, the pristine ZnO and ZnO:Ga nanorods, exhibited strong ferromagnetic characteristics. Photocatalytic studies revealed that the ZnO:Ga nanorods exhibited enhanced photocatalytic activity than the pristine ZnO, by degrading methyl orange (MO) in aqueous media under UV light irradiation.

SnS is a promising material for use in thin-film solar cells because of its suitable optoelectronic properties. So far, SnS thin films with a cubic crystal structure, prepared by chemical bath deposition, with long deposition times and low film thicknesses have been reported. Herein, we report the rapid fabrication of cubic SnS films by increasing the concentration of ammonia(aq) in the solution. SnS films deposited with low ammonia(aq) (0.1875 M) took 6 h to form 400 nm film, and the films were mixedphase. Increasing the concentration from 0.375 to 0.5625 M increased the film thickness from 600 to 1000 nm, with a deposition time of 6 h, and the formation of single-phase SnS. Further increase in the concentration from 0.75 to 0.9375 M decreased the deposition time to 4 h and increased the film thickness (1100–1300 nm). Again, increasing the concentration further to 1.125 M decreased the deposition time to 2 h and film thickness to 900 nm. Thus, increasing the concentration of ammonia(aq) increases the thickness of cubic SnS formed and decreases the deposition time. This work proposes a very useful technique for producing good-quality cubic SnS thin films in a short deposition time of 2–4 h.

In this study, we attempted to synthesize ZnO nanoparticles with various Eu3+ doping concentrations by a simple coprecipitation method for multifunctional applications. Morphology studies of the synthesized samples revealed the presence of hexagonal-shaped and monodispersed particles. A slight shift in the X-ray diffraction patterns of the Eu3+-doped ZnO samples confirmed the successful incorporation of the dopant ions into the host crystal. A change in the E2 (high)-mode intensity was ample evidence of intrinsic defects associated with the oxygen atoms. Diffuse reflectance spectroscopy studies provided sufficient evidence of tuning of the bandgap of ZnO by Eu3+ doping, with a typical red shift. X-ray photoelectron spectroscopy studies revealed the presence of Eu with a +3 state in the ZnO lattice. All the doped ZnO nanoparticles exhibited typical room-temperature ferromagnetism (RTFM). The Eu3+-doped samples displayed a higher photocatalytic degradation (PCD) of RhB dye under UV light illumination compared with the undoped ZnO nanoparticles. Thus, Eu3+ doping is an effective approach for enhancing the RTFM and PCD properties of ZnO for spintronic and photocatalytic applications.

In the present investigation, we made an endeavor to fabricate the ZnO nanoparticles and achieved the tunable properties with Nd doping. The Nd-doped ZnO nanoparticles were characterized via X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) studies that confirmed the successful doping of Nd ions in the ZnO crystal lattice without amending its hexagonal phase. The particle morphology revealed nearly spherical particles with uniform size distribution. The band gap of these samples was determined using diffuse-reflectance spectra (DRS) and was found to vary from 3.17 to 3.21 eV with increasing Nd concentration. A broad and intense emission band at 1083 nm for Nd doped ZnO nanoparticles is observed and is assigned to corresponding emission transition 4F3/2 → 4I11/2 of Nd3+ ions. Furthermore, the magnetic studies indicate that the Nd doping altered the magnetic behavior of nanocrystalline ZnO particles from diamagnetic to ferromagnetic at 300 K and that the magnetization of these samples decreased with increasing Nd concentration. The tunable optical band gap as well as room-temperature ferromagnetism of these samples may find applications in both optoelectronics and spintronics.

Herein, the growth of large-grained and compact Sb2S3 thin films with good electrical properties by Sn doping using a chemical bath deposition (CBD) and annealing approach is detailed. Sn-doped Sb2S3 thin films were prepared using the CBD method with SbCl3, SnCl2.2H2O, and Na2S2O3 as source materials, and ethylenediamine tetraacetic acid (EDTA) as the complexing agent at 40 ° C for 3 h followed by annealing at 250 °C for 30 min under Ar ambience. Un-doped Sb2S3 films exhibited an orthorhombic crystal structure with lattice parameters of a= 1.142 nm, b= 0.381 nm, and c= 1.124 nm, crystalline grain sizes of 100 nm, a direct optical band gap of 1.70 eV, p-type electrical conductivity with high electrical resistivity, and low hole mobility. With Sn doping, a significant increase in the grain size of the films from 6 to > 10 μ m was observed with increasing Sn content from 1.0 to 5.5 at% followed by a decrease in the grain size. The direct optical band gap of the films was 1.71–1.72 eV. By varying Sn at%, the electrical resistivity of the films decreased, and hole mobility increased from 117 to 205 cm2 V−1 s−1 up to 5.5 at% and decreased to 166 cm2 V−1 s−1 at 7.2 at%. With the addition of 1.0–5.5 at% Sn in the Sb2S3 films, the grain growth and electrical properties of the films were drastically enhanced, which is beneficial for the fabrication of planar heterojunction solar cells.

In recent years, CuSbS2 has attracted significant research interest because of its direct optical band gap of 1.5 eV, high optical absorption coefficient, p-type electrical conductivity, and composition involving earth-abundant and non-toxic precursor elements. We prepared CuSbS2 thin films by annealing chemically grown Sb2S3 and sputter deposited Cu (Sb2S3/Cu) stacks in a graphite box, and studied the effect of the Cu/Sb ratio on the growth and properties of these films by varying the thickness of Cu while keeping the thickness of Sb2S3 constant. The Cu/Sb ratio significantly impacted the phase purity, grain growth, and morphology of the CuSbS2 films. The CuSbS2 films prepared with a Cu/Sb ratio of 0.78 showed some unreacted Sb2S3 and nonuniform grain growth. Upon increasing the Cu/Sb ratio from 0.85 to 0.97, the Sb2S3 phase was consumed completely, and phase-pure CuSbS2 with homogeneous grain formation was obtained. These films exhibited an orthorhombic crystal structure with the (410) preferred orientation. Further increase in the Cu/Sb ratio from 1.28 to 1.52 resulted in a change in the growth direction along the (200) plane and the formation of several micron-sized grains with a compact morphology and Cu3SbS4 secondary phase. The direct optical band gap of the films decreased from 1.52 to 1.48 eV when Cu/Sb ratio was increased from 0.91 to 1.28. The films exhibited p-type electrical conductivity and their electrical resistivity decreased with increasing Cu/Sb ratio. From this investigation it was clear that deviation in the Cu/Sb ratio from the stoichiometric proportion leads to inhomogeneous grain growth of CuSbS2 films, which affect the performance of devices using these films.

In this paper, we report the fabrication of Cu4SnS4 thin films by annealing chemically deposited SnS–CuS precursors at 823 K for 90 min, and we studied the effect of the (N2 + S2) pressure during annealing on the growth and properties of the Cu4SnS4 films. Films prepared at a (N2 + S2) pressure of 1.3 kPa exhibited an orthorhombic crystal structure with lattice parameters of a = 1.371 nm, b = 0.766 nm, and c = 0.643 nm, a grain size of 3–6 μm, a direct optical band gap of 1.0 eV, p-type electrical conductivity, and a hole mobility of 69.5 cm2 V−1 s−1. Increasing the (N2 + S2) pressure from 1.3 kPa to 66.7 kPa increased the grain size to more than 6 μm and the hole mobility to 150 cm2 V−1 s−1 at 26.7 kPa and then decreased to 86 cm2 V−1 s−1 at 66.7 kPa. Further increasing the (N2 + S2) pressure to 101.3 kPa resulted in the formation of a monoclinic Cu2SnS3 secondary phase. This study reveals that an annealing temperature of 823 K and a (N2 + S2) pressure of 1.3–66.7 kPa are the optimized conditions to obtain large-grained Cu4SnS4 films free of secondary phases with good optical and electrical properties.

Terbium (0, 2, and 4 at%)-doped ZnS quantum dots (QDs) were synthesized via a solvothermal method. The crystal structures of the synthesized QDs were determined to be zinc blend by X-ray powder diffraction (XRD) and Raman analyses. Transmission electron microscopy (TEM) studies revealed that particles with a mean size of 2–4 nm were formed. An X-ray photo electron spectroscopy (XPS) examination disclosed the existence of terbium with a trivalent state in the ZnS host lattice. The absorption bands of all QDs were located around 325 nm (3.81 eV) and were higher than that of the bulk ZnS band gap (3.67 eV), consistent with the quantum confinement effect. The photoluminescence spectra of the terbium-doped samples displayed five emission peaks at 467 nm (5D4→7F3), 491 nm (5D4 → 7F6), 460 nm (5D4 – 7F5), 484 nm (5D4 – 7F4), and 530 nm (5D4 – 7F3), respectively. The terbium-doped QDs exhibited a higher photocatalytic activity during the degradation of crystal violet dye under UV-light illumination compared to the undoped ZnS QDs. These interesting properties of terbium-doped ZnS QDs are potentially useful for both luminescent and photocatalysis applications.

Nowadays, diluted magnetic semiconductors with improved ferromagnetic feature is utterly seeking for use in modern spintronic applications.We describe the optical as well as magnetic properties of CdS, CdS:Cr, CdS:(Cr + Al), and CdS:(Cr + Mn) co-doped samples. The substitution of Cr dopant and co-dopant ions (Al and Mn) in the host sites were confirmed through structural analysis. Declining of energy band gap with the incorporation of Cr dopant and co-dopant ions (Al and Mn) into the CdS host lattice was estimated through optical studies. Room-temperature magnetic hysteresis curves revealed that pure CdS exhibited paramagnetic nature due to its surface defects, whereas CdS:Cr, CdS:(Cr + Al), and CdS:(Cr + Mn) co-doped nanoparticles showed better ferromagnetic characteristics. Among all synthesized nanoparticles, CdS:(Cr + Al) semiconductor sample exhibited enhanced ferromagnetic nature and may benficial for spintronic applications.

The tunable room-temperature ferromagnetism (RTFM) of ZnO nanoparticles through Dy doping were fabricated through a simple co-precipitation method for spintronic device applications. The synthesized samples were analyzed by studying their structural, morphological, optical, chemical, and magnetic properties. X-ray diffraction, selected area electron diffraction, and X-ray photoelectron spectroscopy results display that the Dy3+ have successfully entered for a few of the Zn2+ as a substitute in the ZnO crystal lattice without altering their hexagonal structure. Morphology studies of the suspensions consist of monodisperse and slightly hexagonal shaped nanoparticles. The tunable optical band gap was observed in the ZnO samples via Dy doping, confirmed by diffuse reflectance spectroscopy studies. Declaration of RTFM of the ZnO:Dy has been established with the noticed hysteresis in M–H loops and these studies indicate that the saturation magnetization of the ZnO sample as a function of Dy content. Amalgamating with the above results, it is suggested that, the observed RTFM in the ZnO:Dy nanoparticles may be interpreted by the contribution of the magnetic moments from the unpaired 4f electrons of Dy3+ ions.

Famatinite (Cu 3 SbS 4 ) thin films were prepared by annealing chemically grown Sb 2 S 3 –CuS stacks in a graphite box at 370–430 °C for 30 min under sulfur and N 2 atmospheres. The films grown at 370 °C contain a minor CuSbS 2 phase with dominant Cu 3 SbS 4 . Those films prepared at 400 °C and 430 °C are single-phase Cu 3 SbS 4 with a tetragonal structure and lattice parameters a = 0.537 nm and b = 1.087 nm and a crystallite size of 25 nm. The grain size of the films increases as the annealing temperature is increased to 400 °C and subsequently decreases. The film morphology is compact and void-free with a grain size of 300–800 nm at 400 °C. The band gap of the films is 0.89 eV. The films exhibited p-type electrical conductivity and a relatively high hole mobility of 14.70 cm 2 V −1 s −1 at 400 °C. Their attractive optoelectronic properties suggest that these films are suitable as solar cell absorber layers.

Monoclinic $$\text {Cu}_{2}\text {SnS}_{3}$$ (CTS) thin films are prepared by annealing chemically deposited SnS–CuS precursors at 520-580 $$^{\circ }\text {C}$$ in a graphite box under atmospheric ( $$\text {N}_{2}+\text {S}_{2}$$ ) pressure, and the effects of annealing temperature and time on the grain growth and morphology of the films are investigated. The films prepared at 520 and 550 $$^{\circ }{\text{C }}$$ show improvement in grain size and the formation of uniform and compact grains with increasing annealing time. The films prepared at 580 $$^{\circ }\text {C}$$ exhibit good grain growth with grain sizes $$\sim 1.0{-}3.0\,\upmu \text {m}$$ ; however, the grain size does not increase with annealing time. Further, annealing time of 120 min at 550 and 580 $$^{\circ }\text {C}$$ leads to material loss. A small amount of $$\text {Cu}_{4}\text {SnS}_{4}$$ is detected in the films. In addition, annealing the films at 550 and 580 $$^{\circ }\text {C}$$ for 90 min with decreased CuS thickness results in a reduction of $$\text {Cu}_{4}\text {SnS}_{4}$$ phase, homogeneous grain growth with grain sizes of $$2.0{-}3.5\,\upmu \text {m}$$ throughout the film thickness, and hole mobilities in the range of $$6.0{-}5.3\,\text {cm}^{2}\,\text {V}^{-1}\,\text {s}^{-1}$$ . These results demonstrate the effectiveness of this annealing approach for producing high quality CTS films with micron-sized grains, which is useful for improving the efficiency of CTS-based thin film solar cells.

We report the growth of SnS 2 thin films by annealing chemically deposited cubic SnS films under a sulfur atmosphere in a graphite box. The chemically deposited SnS films were annealed in the temperature range of 200–550 °C to understand its influence on the conversion of SnS into SnS 2 . In the X-ray diffraction analysis, the as-deposited SnS films annealed in the temperature range of 200–250 °C showed the formation of a minor SnS 2 phase along with the dominant SnS phase. The films annealed at 300 °C contained mixed phases of SnS and SnS 2 . Increasing the annealing temperature from 350 to 500 °C led to the formation of only the dominant SnS 2 phase. Further increasing the annealing temperature to 550 °C gave rise to the formation of a highly oriented SnS 2 film with hexagonal structure having (001) as the preferred orientation. The crystallite size of the SnS 2 films was found to increase from 17 nm to 25 nm with increasing annealing temperature from 350 °C to 550 °C. The lattice parameters were found to be a = 0.365 nm and c = 0.592 nm. Raman spectroscopy analysis confirmed the formation of single phase SnS 2 films at annealing temperatures above 350 °C. The morphological studies showed the conversion of the round shaped grains into flake-like ones on annealing at temperatures above 350 °C. These flakes increased in size on increasing the annealing temperature from 350 °C to 500 °C. The direct optical band gap of these SnS 2 films was found to be 2.58 eV.

High-quality Cu4SnS4 thin films are prepared by annealing chemical bath-deposited SnS–CuS stacks in a graphite box. The effects of annealing temperature on the grain growth and morphology of these films are investigated in this study. Results showed that the films prepared at 500–580 °C yielded an orthorhombic crystal structure with lattice parameters a = 1.371 nm, b = 0.766 nm and c = 0.643 nm, a crystallite size of 260 nm, an increased grain size from 2 μm to greater than 6 μm, a direct optical band gap of 1.0 eV, and p-type electrical conductivity. The films prepared at 550 °C and 580 °C exhibited a relatively high hole mobility of 150 cm2V−1s−1. These properties suggest that the films developed in this study can yield reasonable device efficiency when used as solar cell absorber layers.

Undoped, Gd doped, and (Gd, Mn) co-doped ZnO nanoparticles were fabricated via a hydrothermal method and their structural, morphological, optical, and magnetic properties were examined. X-ray diffraction and Raman spectroscopy studies confirmed that the Gd and Mn ions successfully entered the ZnO hexagonal lattice as substitute ions without changing the internal structure of the lattice. Morphology studies revealed that the synthesized nanoparticles were monodisperse and closely hexagonal shaped. The reflectance spectra showed a red shift of the absorption edge in both doped and co-doped samples. The diamagnetic ZnO sample was altered into a ferromagnetic material when doped with Gd ions, but this behavior was suppressed when Mn ions were co-doped into the matrix.

Dilute magnetic semiconductors with extended ferromagnetic properties are heavily sought for use in next-generation spintronic devices. In this work, we show that co-doping 3 at% Al into Zn 0.44 Gd 0.03 O 0.50 nanoparticles can change their magnetic nature from weak to well-defined ferromagnetism (FM) at room temperature. X-ray diffraction (XRD), selected area electron diffraction (SAED), and Raman spectroscopy show that the Gd and Al atoms replaced the Zn atoms in the ZnO crystal lattice without forming other impurity phases. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analyses of the suspensions revealed the high crystallinity and monodispersity of the 34–44 nm nanoparticles. The undoped and Gd-doped ZnO samples showed diamagnetism and weak FM, while the (Gd, Al) co-doped samples exhibited robust room temperature FM. The enhanced FM of the Zn 0.44 Gd 0.03 Al 0.03 O 0.50 sample can be achieved by increasing the carrier concentration via Al co-doping.

Cu 3 SbS 4 is a promising material for thin film heterojunction solar cells owing to its suitable optical and electrical properties. In this paper, we report the preparation of Cu 3 SbS 4 thin films by annealing the Sb 2 S 3 /CuS stacks, produced by chemical bath deposition, in a graphite box held at different temperatures. The influence of annealing temperature on the growth and properties of these films is investigated. These films are systematically analyzed by evaluating their structural, microstructural, optical and electrical properties using suitable characterization techniques. X-ray diffraction analysis showed that these films exhibit tetragonal crystal structure with the lattice parameters a=0.537 nm and b=1.087 nm. Their crystallite size increases with increasing annealing temperature of the stacks. Raman spectroscopy analysis of these films exhibited modes at 132, 247, 273, 317, 344, 358 and 635 cm −1 due to Cu 3 SbS 4 phase. X-ray photoelectron spectroscopy analysis revealed that the films prepared by annealing the stack at 350 °C exhibit a Cu-poor and Sb-rich composition with +1, +5 and −2 oxidation states of Cu, Sb and S, respectively. Morphological studies showed an improvement in the grain size of the films on increasing the annealing temperature. The direct optical band gap of these films was in the range of 0.82–0.85 eV. Hall measurements showed that the films are p-type in nature and their electrical resistivity, hole mobility and hole concentration are in the ranges of 0.14–1.20 Ω-cm, 0.05–2.11 cm 2 V −1 s −1 and 9.4×10 20 –1.4×10 19 cm −3 , respectively. These structural, morphological, optical and electrical properties suggest that Cu 3 SbS 4 could be used as an absorber layer for bottom cell in multi-junction solar cells.

We report a detailed investigation of the effect of post-deposition annealing on the growth and physical properties of chemically grown cubic SnS films. Chemically deposited cubic SnS films were subjected to annealing in a graphite box with loaded elemental sulfur under N 2 at 150−350 °C for 10, 30, and 60 min in order to understand the grain growth and morphology of the films. Films annealed at 150−250 °C for 10 min showed improved grain size and a more uniform grain morphology. Films annealed at 150−250 °C for 30 and 60 min showed a decrease in the grain size and non-uniform grain morphology for the cubic SnS phase. Films annealed at 300 and 350 °C for 10 min revealed the formation of minor secondary phase SnS 2 , and the grain morphology changed from round shape to flake-like. Longer annealing at 300 and 350 °C improved the extent of the SnS 2 phase, and it was found to be the dominant phase after annealing at 350 °C for 60 min. The direct optical band gap of SnS films is 1.75−1.67 eV, depending on the annealing temperature and time. The films exhibited p-type electrical conductivity. The films annealed at 250 °C for 10 min showed a higher hole mobility of 77.7 cm 2 V −1 s −1 . Thus, lower annealing temperatures and shorter annealing times are favorable conditions to produce high-quality cubic SnS films.

ZnO/Sm (0, 2, and 4 at.%) nanopowders have been prepared by using chemical refluxing method and characterized to understand their chemical, structural, optical, as well as magnetic properties. Energy dispersive X-ray analysis (EDAX) spectra confirmed the existence of zinc, samarium, and oxygen in the prepared samples with expected ratios. X-ray diffraction (XRD) studies indicate that the Sm has been successfully incorporated in the ZnO host matrix. The average diameter of the particles confirmed by transmission electron microscopy (TEM) studies was in the range 14–20 nm. X-ray photoelectron spectroscopy (XPS) analysis divulged that the Sm ions existed in trivalent (+ 3) state in the doped ZnO lattice. Magnetic measurements showed that the undoped ZnO was diamagnetic and the Sm-doped ZnO nanopowders were paramagnetic at 300 K. The paramagnetic nature of the doped samples may be attributed to the random distribution of the Sm 3+ ions in ZnO lattice, giving rise to the formation of a weak interaction.

The creation of oxide based magnetic materials has attracted a great deal of scientific attention, owing to their novel applications in optoelectronic, memory, and spintronic device applications. In this study, the authors report upon the structural, optical, and magnetic properties of Co-substituted CeO2 nanocrystals synthesized via the wet chemical precipitation method. The obtained nanoparticles show good crystallinity as well as an FCC structure with an Fm3m space group of host CeO2 lattice, as confirmed by an X-ray diffraction results. It is noted that Co substitution at low concentrations enhances the photoluminescence characteristics of CeO2 nanoparticles, while higher concentrations significantly reduce the intensity of PL emission, as revealed by PL studies. The estimated M − H loops illustrate that pristine CeO2 shows a paramagnetic nature, while all Co-substituted samples were ferromagnetic in nature. Furthermore, magnetic parameters such as saturation magnetization (MS) and residual magnetization (MR) increased with the inclusion of Co content, reaching a maximum at 4 at% Co and quenching at 6 at% and 8 at% of Co-substitution. In particular, Ce1-xCoxO2 (x = 0.04) nanoparticles show better luminescence and magnetic characteristics than the remaining concentrations.

Impurity free cobalt 3d and erbium 4f co-doped ZnS nanoparticles (NPs) were synthesized using a chemical reflux technique. The as-synthesized NPs exhibited high crystallinity and a narrow particle-size distribution. X-ray diffraction and optical analysis showed that cobalt (II) and erbium (III) ions substituted the zinc (II) ions in tetrahedral sites. The tunable bandgap for ZnS NPs was attained through mono- and co-doping. The cobalt and erbium co-doped NPs displayed a robust magnetization with an enhanced coercivity at room temperature compared with the cobalt-doped ZnS NPs; this was due to the exchange interaction between the cobalt (II) electrons as well as the localized carriers incited through the erbium (III) co-doping. The sense captured with the regulating bandgap and ferromagnetic property in a single substance opens a new platform for advanced applications in optoelectronics and spintronic devices.

Recently, thin films of cubic SnS emerges as a promising solar cell absorber layer owing to its suitable optical and electrical properties. In this paper, we report the growth of cubic SnS thin films by a chemical bath deposition technique using ethylene diamine tetra-acetic acid (EDTA) as the complexing agent. Optimization of EDTA concentration has been carried out to increase the film thickness and to obtain compact and uniform cubic SnS films with good grain size. SnS films with a thickness in the range 500− 620 nm could be obtained with increasing the EDTA concentration in the solution for a deposition time of 6 h. The X-ray diffraction analysis of these films revealed the presence of cubic SnS with (222) and (400) as the preferred orientations. The lattice parameter of these films is found to be a = 1.158 nm and their crystallite size increases from 46 nm to 60 nm with increase in the EDTA concentration from 0.075 M to 0.125 M. Raman spectroscopy analysis revealed the presence of a minor SnS 2 secondary phase in these films. X-ray photoelectron spectroscopy analysis revealed that Sn and S exhibit oxidation states of +2 and −2, respectively in these films. Scanning electron microscopic studies showed that the grain size first increased with increasing EDTA concentration from 0.075 M to 0.10 M and then decreased when the EDTA concentration is further increased to 0.125 M in the solution. The films deposited with an EDTA concentration of 0.10 M are compact and uniform with an average grain size of ∼1 μ m. The direct optical band gap of these films, estimated from their spectral transmittance (T λ ) and reflectance (R λ ) data, is found to increase from 1.67 eV to 1.73 eV with increase in the EDTA concentration from 0.075 M to 0.125 M in the solution. Hall Effect measurements showed that the films are p-type in nature. The films deposited with 0.10 M EDTA concentration exhibited higher hole mobility of 28.6 cm 2 V −1 s 1 , resistivity of 1.53 × 10 5 Ω cm and carrier concentration of 2.86 × 10 12 cm −3 . The above properties suggest that the films deposited from solution with 0.10 M EDTA concentration could be useful as solar cell absorber layer to obtain reasonable device efficiency.

Cubic SnS is a promising absorber material for thin film heterojunction solar cells. In this paper, we report the fabrication of cubic SnS films by chemical bath deposition technique. The effects of bath temperature and Na 2 S 2 O 3 concentration on the properties of the films were investigated. Films deposited at different bath temperatures showed a slightly Sn-rich composition. An increase in the bath temperature from 25 °C to 65 °C caused increase in the crystallite size from 17 nm to 70 nm. An increase in the bath temperature to up to 45 °C resulted in an improvement in the grain size, whereas a further increase in the bath temperature resulted in a slight decrease in the grain size. The band gap of the films decreased from 1.74 eV to 1.68 eV with increasing bath temperature. The films deposited from solutions on increasing the Na 2 S 2 O 3 concentration showed a slight improvement in the atomic percentage of S. The films deposited with a Na 2 S 2 O 3 concentration of 0.125 M showed a compact and uniform morphology with a grain size of ∼1 μm. With an increase in the Na 2 S 2 O 3 concentration from 0.125 M to 0.175 M in the solution, the band gap of the films increased from 1.73 eV to 1.82 eV. The films exhibited p-type electrical conductivity. The films deposited with the Na 2 S 2 O 3 concentration of 0.125 M showed a higher hole mobility of 75.1 cm 2 V −1 s −1 . Thus, the above results showed that a bath temperature of 45 °C and Na 2 S 2 O 3 concentration of 0.125 M are the optimum conditions for obtaining near-stoichiometric cubic SnS films with good structural, microstructural, optical and electrical properties.

ZnS:Tb3+ (0, 1, 3, and 5 at.%) NPs were synthesized via a hydrothermal method using polyethylene glycol as a stabilizer. The prepared samples were characterized systematically using various characterization techniques, such as energy dispersive X-ray spectroscopy, high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry .The XRD studies showed that all of the samples exhibited a cubic structure without any secondary phases. The formation of ultrafine (

$$\hbox {Cu}_{3}\hbox {SnS}_{4}$$ thin films were deposited onto soda-lime glass substrates held at $$360\,^{\circ }$$ C using spray pyrolysis technique. The influence of thiourea concentration on the growth and properties of these films is studied by varying the thiourea concentration (0.04–0.09 M) and keeping cupric chloride (0.015 M) and stannic chloride (0.005 M) concentrations as constant in solution. These films were analyzed by studying their elemental composition, structural, microstructural, optical and electrical properties using appropriate characterization techniques. X-ray diffraction and Raman spectroscopy analyses revealed that the films deposited from solutions with 0.04 and 0.05 M thiourea concentrations contain CuS and $$\hbox {Cu}_{2}\hbox {SnS}_{3}$$ (CTS) phases, respectively. Nanocrystalline $$\hbox {Cu}_{3}\hbox {SnS}_{4}$$ films with cubic structure could be obtained by increasing the thiourea concentration from 0.07 to 0.09 M in the starting solution. The lattice parameter and crystallite size of these films are found to be 0.540 and 6 nm, respectively. The direct optical band gap of these films is found to decrease from 1.75 to 1.70 eV with increasing the thiourea concentration from 0.07 to 0.09 M in the solution. The room temperature electrical resistivity of these films is found to lie in the range $$1.9\times 10^{-3}$$ – $$0.9\times 10^{-3}\Omega$$ cm.

This paper reports the structural as well as the magnetic properties of ZnS:Eu 3+ (0, 1, 2, 3, and 4 at%) nanoparticles prepared by a hydrothermal method. The compositional, structural and magnetic properties of ZnS:Eu 3+ nanoparticles were investigated by energy dispersive X-ray spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry (VSM) measurements. XRD studies confirmed that all the samples had a cubic structure with good crystallinity. TEM showed that the particles were polycrystalline with a mean size of 5–8 nm. XPS revealed the oxidation state of the Eu in the ZnS lattice to be +3. All the Eu 3+ -doped ZnS nanoparticles exhibited room temperature ferromagnetic behavior as a function of doping concentration. The observed RTFM may be interpreted by the contribution of the magnetic moments from the unpaired 4 f electrons of Eu 3+ in the ZnS:Eu 3+ nanoparticles. The interesting magnetic properties of ZnS:Eu 3+ nanoparticles may be further explored for new generation spintronic devices.

The present study describes the elemental and structural as well as the room temperature magnetic properties of pure ZnS, Zn0.96Eu0.04S, and Zn0.95Eu0.04Tb0.01S NPs. The energy dispersive X-ray spectroscopy (EDAX) perceived the existence of zinc, terbium, europium, and sulfur in the prepared samples in expected stoichiometry ratio. X-ray diffraction (XRD) studies revealed that all the prepared NPs had a cubic structure. Transmission electron microscopy (TEM) studies showed the creation of wispy particles with an average size in the range of 5–8 nm. Magnetization (M) versus applied magnetic field (H) studies indicated that the pure ZnS NPs exhibited diamagnetic behavior, whereas both Zn0.96Eu0.04S and Zn0.95Eu0.04Tb0.01S NPs evinced the ferromagnetic nature at room temperature. However, suppression in ferromagnetism was observed in Zn0.95Eu0.04Tb0.01S compared to Zn0.96Eu0.04S nanoparticles due to the interactions between the Eu–Eu ions, Tb–Tb ions, and Eu–Tb ions. The above experimental results suggesting that both doped and co-doped ZnS nanoparticles are useful for spintronic device applications.

The compositional, structural, optical and magnetic properties of ZnS , Zn 0.98 Co 0.02 S, Zn 0.98 Sm 0.02 S and Zn 0.96 Co 0.02 Sm 0.02 S nanoparticles synthesized by a hydrothermal method are presented and discussed. X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) studies revealed that all the samples exhibited cubic structure without any impurity phases. X-ray photoelectron spectroscopy (XPS) results revealed that the Co and Sm ions existed in +2 and +3 states in these samples. The photoluminescence (PL) spectra of all the samples exhibited a broad emission in the visible region. The room temperature magnetization versus applied magnetic field ( M – H ) curves demonstrated that the Sm+Co doped nanoparticles exhibited enhanced ferromagnetic behavior compare to Co and Sm individually doped ZnS nanoparticles, which is probably due to the exchange interaction between conductive electrons with local spin polarized electrons on the Co 2+ or Sm 3+ ions. This study intensifies the understanding of the novel performances of co-doped ZnS nanoparticles and also provides possibilities to fabricate future spintronic devices.

Cu 2 SnS 3 (CTS) is a promising candidate for thin film solar cells due to its suitable optical and electrical properties. In this paper, we report the growth of CTS thin films by co-evaporation of Cu, Sn and S onto soda-lime glass substrates held at 350 °C. The effect of annealing temperature on the growth and properties of these films is investigated by studying their structural, microstructural, optical and electrical properties using appropriate characterization techniques. XRD and Raman analyses revealed that the co-evaporated films contain CTS, CuS and Cu 4 SnS 4 phases. On annealing these films at 520 °C for 10 min, Cu 1.9375 S emerges as a secondary phase, CTS being dominant phase. Further increase in the annealing temperature from 550 °C−580 °C leads to the elimination of Cu 1.9375 S phase completely. The films are found to be near-stoichiometric and polycrystalline CTS with monoclinic structure having ( 1 ¯ 31)/(200) preferred orientation. The crystallite size of the annealed CTS films is found to be 70 nm. The surface morphology of the films annealed at 550 °C for 10 min is found to be compact with grain size in the range 100 nm−500 nm. The direct optical band gap of these films is found to be 0.97 eV.

This paper reports the synthesis and characterization of ZnS:Gd nanoparticles prepared by a hydrothermal process using different doping concentrations. The chemical, structural, luminescence and magnetic properties of these nanoparticles were investigated by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, and vibrating sample magnetometer (VSM) measurements. XRD confirmed that all the samples had a cubic structure with good crystallinity. HRTEM showed that the particles were polycrystalline with a mean size of 4–6 nm. XPS revealed the oxidation state of Gd in the ZnS lattice to be +3. The PL spectra of all the nanoparticles exhibited broad emission peaks in the visible region. All the Gd doped nanoparticles exhibited well-defined ferromagnetic behavior at room temperature. The saturation magnetization increased significantly with increasing Gd concentration, reaching a maximum for 3 at.% Gd and decreasing for the 5 at.% Gd doped ZnS nanoparticles.

Zn1−xDyxS (x=0, 0.02 and 0.04) nanoparticles (NPs) were synthesized by chemical refluxing technique at 100 °C. The prepared samples were analyzed by studying their compositional, morphological, structural, optical and magnetic properties. EDS analysis confirmed the presence of zinc, dysprosium and sulfur in the samples in near stoichiometric ratio. The X-ray diffraction patterns do not show any Dy related peaks for the as-synthesized ZnS nanoparticles. The average diameter of the particles confirmed by TEM studies, was in the range 2–4 nm. Raman studies revealed that all the samples are single phase and exhibit cubic structure. From DRS studies, the band-gap was found to be in the range of 3.85–3.70 eV. All the doped ZnS nanoparticles exhibit ferromagnetic behavior with the Curie temperature higher than room temperature and the magnetic properties of doped ZnS nanoparticles depend on the concentration of Dy ions.