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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.

Nano-ZnO and ZnO doped with Cu: Mn samples (Mn = 2% and Cu = 2% and 4%) have been synthesized by combustion synthesis. The effect of Cu content (Cu/Mn co-dopant) on the structural, optical, and magnetic properties has been studied. X-ray diffraction studies revealed hexagonal Wurtzite structure, and the particle size is around 36–18 nm. From scanning electron microscopy (SEM) analysis, morphology of all the samples was spherical in shape with high porous structure. The elemental composition of the synthesized samples was investigated using energy dispersive X-ray analysis (EDAX), which confirmed the presence of selective elements in the samples near stoichiometric ratio. FTIR spectra confirmed the presence of functional groups in synthesized samples. From UV–Vis absorbance spectra, blue shift is observed with increasing dopant concentration. From VSM studies, the enhanced magnetization properties were observed in doped samples. From photoluminescence (PL) studies, decrease in rate of recombination of electron–hole pairs is observed. The simultaneous enrichment of magnetic and optical properties of Cu doped ZnO: Mn nanoparticles can be used in future spintronic and optoelectronic devices.

ZnO nanoparticles at different temperatures were synthesized by using the combustion method. The effect of synthesis temperature on the properties of the nanoparticles was studied by using XRD, FESEM, EDS, TEM, photoluminescence (PL), Raman, diffuse reflectance spectra (DRS), and VSM characterization techniques. The XRD results reveal that the grown nanoparticles have a hexagonal wurtzite structure without any impurities and agreed with EDS results. FESEM and TEM micrographs show that the ZnO nanoparticles possess a spherical shape with agglomeration free, and the size increases with increase of synthesis temperature. From DRS studies, it was noticed that the band gap decreases with increase of synthesis temperature. In PL studies, blue peak at 465 nm may be due to defect-related transitions. A sharp intense peak in Raman spectra at 485 cm−1 represents E2H mode is a characteristic of a hexagonal wurtzite structure. The magnetic studies show that the magnetization decreases from 0.0172 to 0.0042 emu/g as the synthesis temperature increases from 400 to 550 °C. ZnO synthesized at 500 °C has a large squareness ratio. These materials are potential candidates for memory devices.

EDTA surfactant assisted bare and Cu doped CdS nanoparticles were prepared by simple chemical coprecipitation method. As the prepared samples were characterized by energy dispersive analysis of X-rays (EDAX), X-ray diffraction patterns (XRD), transmission electron microscopy (TEM), Raman spectroscopy and photoluminescence spectroscopy (PL). Existence of Cu in host lattice with near stoichiometric ratio was corroborated by EDAX spectra. X-ray diffraction patterns revealed that cubic structure as that of CdS host lattice. TEM images suggested that spherical nature of nanoparticles with a size ranging from 4–6 nm. Room temperature photoluminescence (PL) spectra revealed that pristine host lattice nanoparticles demonstrate a strong green emission peak located at 525 nm as well as weak red emission shoulder situated at 598 nm. Auxiliary in Cu doped CdS samples, the luminescence intensity was gradually reduced as well as the green emission peak was shifted to red region (660 nm). With increase of Cu content in host matrix a red shift is found in the PL emission peak.

A simple sol-gel technique is used to synthesize zero-dimensional pure and Er-doped BiFeO3 (BFO) nanoparticles. The effect of Er dopant on morphology, structure, optical, magnetic, and photoluminescence properties of single-phase BFO was studied. X-ray diffraction (XRD) studies reveal that the structural phase transformation is noticed from rhombohedral to orthorhombic with substitution of Er to pure BFO. From scanning electron microscopy (SEM) and transmission electron microscopy (TEM), morphology of the synthesized samples were spherical in shape. Agglomeration and particle size reduced with substitution of Er, particle size is around ∼ 30 nm. Energy-dispersive analysis of X-ray (EDAX) spectra confirms the presence of selective elements in synthesized samples. Fourier transform infrared spectra (FTIR) confirms that all the bonds strongly correspond to BFO. The substitution of Er in BFO nanoparticles also demonstrates a strong reduction in optical band-gap energy compared with pure BFO. Magnetization studies were carried out by using vibrating sample magnetometer (VSM), and the saturation magnetization increases with increasing substitution of Er. A photoluminescence (PL) spectrum reveals that the substitution of Er suppressed the recombination of electron-hole pairs.

Nanoparticles (Nps) of Ba (0, 1 to 5 at.%)-doped BiFeO3 were synthesized by a sol-gel route at 100 °C using tartaric acid as a chelating agent. The obtained results were studied by using XRD, SEM with EDAX, TEM, UV-vis diffusion reflectance spectra, VSM, and impedance analyzer. EDAX spectra confirmed the presence of Bi, Ba, and Fe in the samples. X-ray diffraction studies showed that BiFeO3 and Bi1−xBaxFeO3 samples exhibited the expected rhombohedral perovskite structure up to a Ba concentration of 3%, whereas 4 and 5% of Ba concentration exhibited the tetragonal phase. TEM studies indicate the particle sizes in the range of 08–28 nm. Reflectance spectra measurements showed a decrease in band gap with increasing Ba concentration. Magnetic properties indicated that the undoped BiFeO3 and Ba-doped BiFeO3 samples were ferromagnetic at room temperature. The dielectric constant (e′) and loss (e″) show large dispersion behavior. The dielectric constant increases with an increase of dopant concentration, but a very high value of the dielectric constant was noticed for x = 0.05.

Here in, we synthesized pure BiFeO3 (BFO) and Bi0.8-XCaXEr0.2FeO3 (x = 0.0, 0.05, 0.1, and 0.15 at.%) nanoparticles using sol–gel technique and investigated their optical, magnetic, and electrical properties. X-ray diffraction studies reveals structural transformation in BFO from the rhombohedral structure to orthorhombic, without forming any defect phases, with the doping of Er or Ca/Er into BFO. EDX analysis confirms the presence of doped elements (Er and Ca) along with the Bi, Fe and O elements corresponding to BFO host material. TEM images indicate the significant reduction in particle size with increasing the Ca dopant concentration. Further, the band gap of pure BFO nanoparticles (2.30 eV) decreases notably to a minimum of 1.81 eV for Ca and Er co-doped BFO nanoparticles. All samples exhibited the ferromagnetic behavior, Bi0.8-XCaXEr0.2FeO3 (x = 0.05 at.%) nanoparticles yielded 2.9 times higher saturation magnetization compared to BFO nanoparticles. In addition, the conductivity increases by 11.8 times for Bi0.8-XCaXEr0.2FeO3 (x = 0.05 at.%) nanoparticles compared to BFO nanoparticles.

Hierarchical 1-D CdS nanorods adorned with MoS2-SnS2 nanocomposites were developed by a simple solvothermal method at nano-regime. In the present work, we noticed a tremendous enhancement in H2 evolution by loading MoS2-SnS2 nanostructures on 1D-CdS nanorods under the solar light irradiation. Notably, for the CdS/MoS2-SnS2 (6 wt%) nanocomposites, the hydrogen production rate reached to 185.36 mmol. h−1. g−1., this is much higher than that of pristine CdS (2.5 mmol. h−1. g−1) and 6 wt% of MoS2 loaded CdS nanorods (123 mmol. h−1. g−1). The efficient photocatalytic performance in MoS2-SnS2 loaded CdS nanorods could be due to high light harvesting capability, bifurcation of electron-hole pairs, trapping sites, active catalytic zones, migration of charge carriers towards the surface of a semiconductor, and suitable energy levels. We strongly believe that the current design plan on the synthesis of MoS2-SnS2 loaded CdS nanorods and its efficiency for catalytic performance towards hydrogen evolution is an inherent alternative route for sustainable energy production.

In the era of modern technology, the development of spintronic devices using diluted magnetic semiconductor nanoparticles has drawn significant attention from the world researchers. In this work, we report on novel Cu1−x Mn x S (x = 0.00, 0.01, 0.03 and 0.05) compounds synthesized at room temperature through a simple precipitation method via EDTA as a capping agent. XRD patterns suggested that the entire synthesized nanoparticles exhibit covellite-phase hexagonal configuration like CuS. Reflectance measurements indicated energy band gap reduction by augmentation of Mn content. Photoluminescence spectra of prepared nanoparticles showed strong blue, green and weak yellow emissions at 471, 533 and 583 nm, respectively. The room-temperature VSM measurements suggested that bare CuS showed a diamagnetic nature, while Mn-doped CuS nanoparticles exhibited paramagnetism, which is enhanced with increasing Mn dopant concentration.

In this paper, we report systematic investigations on the effects of Ni doping on the structural, optical, magnetic and photocatalytic characteristics of CuS nanoparticles synthesized by simplistic wet chemical co-precipitation route via EDTA molecules as templates. XRD studies confirmed that accurate phase formation of synthesized nanoparticles and chemical composition were obtained by EDX. Magnetic measurements revealed that 3% Ni doped CuS nanoparticles show signs of good ferromagnetism at room temperature and transition of magnetic signs from ferromagnetic to paramagnetic nature by increasing the Ni dopant concentration in CuS host matrix. The photocatalytic degradation efficiency of the prepared pure and Ni doped CuS nanoparticles were evaluated as a function of simulated sunlight irradiation via RhB organic dye pollutant as a test molecule. Particularly, in the presence of 3% Ni doped CuS nanoparticles in pollutant solution 98.46% degradation efficiency was achieved within 60 min of sunlight irradiation; meanwhile bare CuS attained only 83.22%. Further, after five cycles 3% Ni doping CuS nanoparticles exhibit good photocatalytic stability with very negligible catalyst loss. We believe that the investigations in this study provides adaptable pathway for the synthesizing of various diluted magnetic semiconductor nanoparticles and their applications in spintronic devices as well as sunlight-driven photocatalysts intended for wastewater purification.

The authors have presented synthesis and structural and magnetic properties of Tb (0, 2, 4, and 6 at.%)doped ZnS semiconducting nanoparticles and employed via chemical co-precipitation process using polyethylene glycol (PEG) as capping agent. X-ray diffraction (XRD) and selected area electron diffraction (SAED) studies confirm the formation of singlephase, cubic structure, nanometric samples (˜10 nm). Highresolution transmission electron microscopy (HRTEM) analyses of the suspensions revealed the size of the particles in the range 5–8 nm. The undoped ZnS sample displayed the expected diamagnetic behavior and the terbiumdoped ZnS samples exhibited room temperature paramagnetic character as a function of Tbdoping concentration.The observed paramagnetism may be due to the random distribution of the terbium ions into the ZnS crystal lattice giving rise to the formation of feeble interaction.

The development of novel highly efficient semiconductor metal oxide catalysts for enhanced photocatalytic dye degradation had of great significance. Herein, we report the synthesis of novel and highly efficient CuO/BiOI nanocomposite (0, 10, 20, 30, 40 wt % of CuO) semiconductor photocatalysts by a facile hydrothermal method. High crystallinity of tetragonal structure had observed from XRD studies. From SEM and TEM studies flower like morphology had observed up to 30% of CuO in CuO/BiOI nanocomposite and for 40% of CuO nanoflower like morphology slightly diminishes. EDAX and XPS spectra depict the presence of Bi, O, I, Cu only no other impurities had observed. Stretching and bending vibrational modes had observed from FTIR analysis. Bandgap decreases gradually upto 30% of CuO in CuO/BiOI nanocomposite and slightly increases for 40% of CuO in CuO/BiOI nanocomposite. Decrease in peak intensity due to charge carriers were observed from Photoluminescence studies Photocatalytic activity had estimated by the degradation of methyl orange (MO) solution under visible light irradiation. The flower-like morphology of 30% CuO in CuO/BiOI nanocomposite showed the high absorption ability to facilitate the generation of charge carriers as well as active oxygen species.

The present work is planned for a simple, inexpensive and efficient approach for the synthesis of Cu1-xFexS (x = 0.00, 0.01, 0.03, 0.05 and 0.07) nanoparticles via simplistic chemical co-precipitation route by using ethylene diamine tetra acetic acid (EDTA) as a capping molecules. As synthesized nanoparticles were used as competent catalysts for degradation of rhodamine-B organic dye pollutant. The properties of prepared samples were analyzed with energy dispersive analysis of X-rays (EDAX), X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-visible optical absorption spectroscopy, Fourier transform infrared (FTIR) spectra, Raman spectra and vibrating sample magnetometer (VSM). EDAX spectra corroborated the existence of Fe in prepared nanoparticles within close proximity to stoichiometric ratio. XRD, FTIR and Raman patterns affirmed that configuration of single phase hexagonal crystal structure as that of (P63/mmc) CuS, without impurity crystals. The average particle size estimated by TEM scrutiny is in the assortment of 5–10 nm. UV-visible optical absorption measurements showed that band gap narrowing with increasing the Fe doping concentration. VSM measurements revealed that 3% Fe doped CuS nanoparticles exhibited strong ferromagnetism at room temperature and changeover of magnetic signs from ferromagnetic to the paramagnetic nature with increasing the Fe doping concentration in CuS host lattice. Among all Fe doped CuS nanoparticles, 3% Fe inclusion CuS sample shows better photocatalytic performance in decomposition of RhB compared with the pristine CuS. Thus as synthesized Cu0·97Fe0·03S nanocatalysts are tremendously realistic compounds for photocatalytic fictionalization in the direction of organic dye degradation under visible light.

Pristine and Co doped covellite CuS nanoparticles were synthesized in aqueous solution by facile chemical co-precipitation method with Ethylene Diamine Tetra Acetic Acid (EDTA) as a stabilizing agent. EDAX measurements confirmed the presence of Co in the CuS host lattice. Hexagonal crystal structure of pure and Co doped CuS nanoparticles were authenticated by XRD patterns. TEM images indicated that sphere-shape of nanoparticles through a size ranging from 5 to 8 nm. The optical absorption edge moved to higher energies with increase in Co concentration as indicated by UV–vis spectroscopy. Magnetic measurements revealed that bare CuS sample show sign of diamagnetic character where as in Co doped nanoparticles augmentation of room temperature ferromagnetism was observed with increasing doping precursor concentrations. Photocatalytic performance of the pure and Co doped CuS nanoparticles were assessed by evaluating the degradation rate of rhodamine B solution under sun light irradiation. The 5% Co doped CuS nanoparticles provide evidence for high-quality photocatalytic activity.

The present paper brings out the results concerning the preparation and optical properties of Sm 3+ and Dy 3+ each ion separately in different concentrations (0.3, 0.5, 1.0 and 1.5 mol.%) and also together doped (x mol.% Dy 3+ + 1.5 mol.% Sm 3+ ): Li 2 O-LiF-B 2 O 3 -ZnO (where x = 0.5, 1.0 and 1.5 mol.%) glasses by a melt quenching method. Structural and thermal properties have been extensively studied for those glasses by XRD and TG/DTA. The compositional analysis has been carried out from FTIR spectral profile. Optical absorption spectral studies were also carried out. Sm 3+ : LBZ glasses have displayed an intense orange emission at 603 nm ( 4 G 5/2 → 6 H 7/2 ) with an excitation wavelength at 403 nm and Dy 3+ : LBZ glasses have shown two emissions located at 485 nm ( 4 F 9/2 → 6 H 15/2 ; blue ) and 574 nm ( 4 F 9/2 → 6 H 13/2 ; yellow ) with an excitation wavelength at 385 nm. Remarkably, it has been identified that the significant increase in the reddish orange emission of Sm 3+ ions and diminished yellow emission pertaining to Dy 3+ ions in the co-doped LBZ glass system under the excitation of 385 nm which relates to Dy 3+ ions. This could be due energy transfer from Dy 3+ to Sm 3+ . The non-radiative energy transfer from Dy 3+ to Sm 3+ is explained in terms of their emission spectra, donor lifetime, energy level diagram and energy transfer characteristic factors. These significantly enhanced orange emission exhibited glasses could be suggested as potential optical glasses for orange luminescence photonic devices.

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.

Nanoparticles of ZnS:Nd (0, 2 and 4 at%) were synthesized by a chemical co-precipitation method at 300 K using PEG as capping agent. The effect of Nd doping on the structural, optical and magnetic properties of ZnS nanoparticles was investigated. EDAX spectra confirmed the presence of Zn, Nd and S in the samples. X-ray diffraction studies showed that all the samples exhibited the expected zinc blende structure. Raman studies revealed the cubic structure and absence of impurities in the undoped and Nd doped ZnS nanoparticles. TEM studies indicated that the particles were a few nm (

Multiferroic BiFeO3 and Bi0.8-XGdXEr0.2FeO3 (X = 0.0, 0.05, 0.1 & 0.15) nanoparticles have been prepared by sol-gel technique. The effect of Gd content (in Gd/Er co-dopant) on the structural, magnetic, dielectric, and optical properties of the BiFeO3 materials has been studied. X-ray diffraction analysis revealed rhombohedral to orthorhombic phase transition of BiFeO3 when doped with Er or Er/Gd. All samples composed of aggregated spherical nanoparticles and the size of the particles is decreased with increasing the Gd content in Gd/Er co-doped BiFeO3 nanoparticles. Energy dispersive spectra confirm the presence of all the selective elements in synthesized samples and are in near stoichiometric ratio. The Fourier transform Infrared spectra confirmed the presence of functional groups of elements of synthesized nanoparticles only. Optical properties of the samples, as studied by UV–visible spectroscopy, showed the decreased optical band gap with increasing the Gd content in Bi0.8-XGdXEr0.2FeO3 nanoparticles. The Er/Gd co-doping in BiFeO3 had a significant effect on the magnetic properties and effectively reduced the leakage current. The simultaneous enrichment of magnetic and electric properties indicates the potential application of Bi0.8-XGdXEr0.2FeO3 (X = 0.0, 0.05, 0.1 & 0.15) nanoparticles in future multifunctional devices.

Photocatalytic H2 generation through water splitting using heterogeneous semiconductor nanostructures under the beneath of sunlight is a significant route for alternation of renewable energy. In this perception we fabricated novel hierarchical CdS/MoS2-CoSe2 nanostructures via facile solvothermal route combined with ultra-sonication technique. Optical studies explored that synthesized nanostructures are most reliable host lattices for harvesting of visible light owing to their optimum energy band gap. The MoS2-CoSe2 encumbered on CdS nanorods component provided immense of hydrogen evolution (191.5 mmolg−1 h−1) with outstanding stability. It is noteworthy that the observed H2 evolution rate is much higher in synthesized structures as compared to numerous reported CdS based nanohybrids. The robust H2 evolution rate and outstanding stability may be owing to fast charge carriers separation and migration between CdS and MoS2-CoSe2, creation of huge surface area and broad light harvesting nature. It is evident from PL, optical, photocurrent and impedance results. From the obtained results we believe that the proposed design strategy is preferable path way to develop new type of photocatalysts with robust H2 evolution rate.