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The present study investigates the effect of precursor solution volume on the structural, morphological, compositional, optical, and electrical properties of In2S3 films. Thin films of In2S3 were deposited by a nebulizer spray pyrolysis technique on glass substrates with varying precursor solution volumes (4 mL, 8 mL, 12 mL, and 16 mL). X-ray diffraction studies confirmed the formation of the tetragonal phase and the compositional studies using energy-dispersive x-ray spectra showed the presence of only indium and sulfur. The energy bandgap of the films was found to be in the range of 2.51–2.4 eV. The I-V characteristics and photoresponses of the photodetectors including photosensitivity, responsivity, and detectivity were evaluated under visible light illumination. Enhanced photo-responsivity was observed with an increase in the precursor solution volume, with a maximum value of 0.213 AW−1 observed for the thin film coated with 12 mL precursor solution volume. For the thin film coated with a volume of 12 mL precursor solution, external quantum efficiency of 69% and detectivity of 20 × 109 Jones were observed. This In2S3 thin film may find application in the fabrication of efficient and cost-effective photodetector devices.

In this paper we demonstrate the use of atmospheric pressure plasma jet (APPJ) to functionalize the surface of hydrothermally synthesized vertically aligned TiO2 nanorods (TNRs) for photo electrochemical (PEC) application. The TNRs functionalized with the atmospheric pressure He-plasma showed relatively higher crystallinity, improved light absorption, and change in the morphology with additional surface area, leading to an enhanced photocurrent density than that of the untreated. Achieving the PEC performance on par with the best in the literature, this APPJ treatment is shown to be a promising technique to obtain better functionality with TNR kind of materials and many other nano-micro systems for various applications such as PEC hydrogen generation.

In the present work, zinc tungstate (ZnWO4) nanoparticles were synthesized by a simple co-precipitation technique without the addition of any templates and complexing agent. The X-ray diffraction study confirmed the formation of monoclinic structure ZnWO4. The annealing temperatures play a significant role on the crystallization of the samples and the crystallite size of ZnWO4 nanoparticles are varied between 30 and 65 nm. The well dispersed spherical solid shells along with nanoplatelet like morphology was obtained from the surface morphological study. The concomitant decrease in optical energy band gap value of ZnWO4 is due to the effect of crystallite size enhancement. It was observed that the crystallinity is one of the primary factors that affect the luminescence property of ZnWO4 nanoparticles. The purity and stoichiometric nature of synthesized product was confirmed by compositional analysis. The highest degradation efficiency of 87% was observed for 300 °C annealed ZnWO4 nanoparticles in the photocatalytic study by the degradation of methylene blue dye under ultraviolet light irradiation. The photocatalytic study confirmed the decomposition of methylene blue after 1 h irradiation.

Cadmium oxide (CdO) thin films doped with different yttrium (Y) concentrations have been prepared by the cost-effective spin coating technique. The effect of Y doping on structural, morphological, linear, and nonlinear optical properties of the as-prepared CdO thin films is studied. The AFM morphology of the thin films revealed grain size increase with the increase in the percentage of Y doping. From the optical properties, it is found that the films are highly transparent and the optical band gap spreads over the range of 2.3–2.8 eV. The Y doping drastically suppresses the linear and nonlinear optical properties.

Hydroxyapatite (HAP) have been widely used as bone implants for its biocompatibility, and bioactivity. Other approaches like scaffold development, drug delivery and nanomaterials preparation are explored recently. Herein, hydroxyapatite incorporated with 5-nitroisatin (HAP-5 N) were prepared and tested for its anticancer potential. The prepared HAP-5 N were found to have rod like structures as seen using scanning electron microscopic analysis. The structural elucidation of 5-nitroisatin were confirmed by performing 2D heteronuclear single quantum correlation experiment. The synthesized HAP-5 N were assessed for its possible role as an anticancer agent against cervical cancer (SiHa) cells. From the study, it was found that HAP-5 N is efficient in inhibiting the growth of cervical cancer cell lines.

The effect of Nd doping (1, 3 and 5 wt%) on the structural, morphological, electrical and optical properties of NiO thin films deposited on glass substrates using nebulizer spray pyrolysis method are investigated. The X-ray diffraction study reveals cubic structure with an improvement in crystallinity upon the incorporation of Nd into NiO lattice. The films are > 50% transparent in the high wavelength region. The absorption spectra witnesses a sharp fall in the wavelength range, 300 nm

Carbon dots (CDs) that exhibit fluorescence properties are generally derived from carbonaceous materials, and possess ultrasmall sizes with various exciting physical, chemical and photo-properties, which have been used in many different fields in recent time. Here, we have focused on the preparation of nitrogen-doped CDs (N-CDs) that emit a bright blue fluorescence upon exposure to UV excitation. Furthermore, by employing Rhodamine B (RhB) as a donor molecule, the emission color of N-CDs is altered from blue to red. Interestingly, the optical tuning based upon emission from one particular color to various other colors has been achieved by varying the doping ratio of the donor molecule, RhB. The reason is mainly attributed to the non-radiative energy transfer of the exciton energy from an excited donor to an acceptor through fluorescence resonance energy transfer (FRET). Furthermore, this emission behavior is explored for the ratiometric sensing of mercury ion (Hg2+) in aqueous medium. Among different color emissions, we chose one particular emission color, namely violet, for the detection of the Hg2+ ion. The photoluminescence properties of N-CDs are effectively and systematically quenched with the addition of different mercury ion concentrations, leading to efficient energy transformation arising from the synergetic effect of the electrostatic interaction and metal - ligand coordination between the surface functional groups of N-CDs and Hg2+ ion. On the other hand, RhB has no interaction with Hg2+ ions. These findings provide a way for developing a cheap, selective and suitable sensing matrix for the detection of toxic metal ions, such as mercury (Hg2+) at a low concentration level.

The influence of polyether compound on the preparation of composite polymer electrolyte (CPE) membrane based on poly(vinylidene difluoride) (PVdF) matrix via spinning cum immersion precipitation technique is investigated with different weight ratios of polyethylene glycol (PEG-6000). The addition of polyether compound into the composite polymer matrix is found to improve the physico-chemical properties such as porosity, electrolyte absorption, and ionic conductivity of the resultant membranes. The maximum ionic conductivity of the fabricated PVdF(80%)/PEG(10%)/BaTiO3(5%) based LiFePO4|B2-CPE|Li system is determined to be 9.4 mS cm−1 at room temperature that is favorable for exhibiting good electrochemical performances. The Li+ transference number is computed to be 0.23 for B2 composite polymer electrolyte based symmetric cell. At 0.2C rate, the LiFePO4|B2-CPE|Li cell showed a good discharge capacity of 144.3 mAh g−1 and improved the capacity retention up to 98.4% after 50 cycles. The findings suggest that the porous composite PVdF electrolyte is a promising candidate for lithium-ion batteries.

This is paper briefly explains the MEMS based piezoelectrically actuated micropump and its applications for the drug delivery system. The micropump is designed and it consists of four elements like electrodes, piezoelectric layer, flexible membrane and a reservoir. It is analyzed for three different materials like PZT-5H, PZT-5A and BaTiO3. Among them BaTiO3 is used as piezoelectric material. By using the FEM tool COMSOL Multiphysics, mechanical behavior of the micropump is evaluated as flow velocity and flow rate of 8.92 m/s and 0.854 ml/min at 50 V respectively. The obtained flow rate for the micropump is best suitable in cardio-vascular, hypertension cases where the drug need to be delivered with an appropriate flow rate.

Magnetic nanoparticles of iron oxide (γ-Fe2O3) have been prepared using bio-assisted method and their application in the field of biosensors is demonstrated. Particularly in this work, different nanostructures of γ-Fe2O3 namely nanospheres (NS), nanograsses (NG) and nanowires (NW) are prepared using a bio-surfactant namely Furostanol Saponin (FS) present in Fenugreek seeds extract through co-precipitation method by following “green” route. Three distinct morphologies of iron oxide nanostructures possessing the same crystal structure, magnetic properties, and varied size distribution are prepared and characterized. The resultant materials are analyzed using field emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, vibrating sample magnetometer and Fourier transform infrared spectroscopy. Moreover, the effect of reaction time and concentration of FS on the resultant morphologies of γ-Fe2O3 nanostructures are systematically investigated. Among different shapes, NWs and NSs of γ-Fe2O3 are found to exhibit better sensing behaviour for both the individual and simultaneous electrochemical detection of most popular biomarkers namely dopamine (DA) and uric acid (UA). Electrochemical studies reveal that γ-Fe2O3 NWs showed better sensing characteristics than γ-Fe2O3 NSs and NGs in terms of distinguishable voltammetric signals for DA and UA with enhanced oxidation current values. Differential pulse voltammetric studies exhibit linear dependence on DA and UA concentrations in the range of 0.15–75 µM and 5 μM – 0.15 mM respectively. The detection limit values for DA and UA are determined to be 150 nM and 5 µM. In addition γ-Fe2O3 NWs modified electrode showed higher sensitivity, reduced overpotential along with good selectivity towards the determination of DA and UA even in the presence of other common interferents. Thus the proposed biosensor electrode is very easy to fabricate, eco-friendly, cheaper and possesses higher surface area suggesting the unique structural patterns of γ-Fe2O3 nanostructures to be a promising candidate for electrochemical bio-sensing and biomedical applications.

This paper reports successful fabrication of copper-doped tin sulphide (SnS:Cu) thin films using nebulized spray pyrolysis. Different Cu doping concentrations (2, 4, 6, and 8 wt-%) were employed to...

Currently several type of energy sources exist in the modern world. The energy makes people's life more comfortable, easy, time savings, fast transformation of information and various modes of transmission. Because of large demand of energy, efforts on production of energy increases day by day which subsequently increase serious environmental concerns such as pollution and lack of existing natural resources. In this respect, several attempts have been proposed for new type of renewable and chemical energy systems to overcome the economic burden, global warming and environmental problems caused by the use of conventional fossil fuels. Hydrogen production via water splitting is a promising and ideal route for renewable energy using the most abundant resources of solar light and water. Cost effective photocatalyst for Photoelectrochemical (PEC) water splitting using semiconductor materials as light absorbers have been extensively studied due to their stability and simplicity. Over the past few decades, various metal oxide photocatalysts for water splitting have been developed and their photocatalytic application was studied under UV irradiation. Alternative semiconductor photocatalyst should harness solar energy in the visible light, one such semiconductor material is indium gallium nitride (InGaN), owing to its suitable and tunable energy band-gap, chemical resistance and notable photoelectrocatalytic activity. This review article is initiated with the brief introduction about the origin and methods of production of hydrogen gas from both renewable and nonrenewable energy sources. Multi-functional properties and applications of InGaN are described along with past and recent efforts of InGaN materials for hydrogen evolution by several investigators are provided in detail. In addition, future prospects and ways to improve the PEC performance of InGaN are presented at the end of this review.

Carbon (C)-coated zinc oxide (ZnO) nanoparticles (NPs) having different sizes and morphologies were successfully synthesized by a flash combustion biomimetic approach using different contents of gelatin as the medium. Structural and vibrational studies indicate that the NPs are grown in a hexagonal wurtzite structure. The amount of gelatin content has a strong effect on the growth mechanism and the physical and optical properties. The presence of C in the ZnO was clearly confirmed by Raman analysis in which the Raman bands corresponding to the presence of C were observed at ∼ 1343 cm−1 (G-band), 1580 cm−1 (D-band), and 2700 cm−1 (G′-band). At low concentrations, the NPs grew in the shape of spherical aggregates which arranged themselves in the form of a spherical flower-like structure. At 1 g of gelatin content, the spherical flower-like structure disappeared to be distributed at 3 g of gelatin content into a uniform planar spherical NP arrangement in the shape of a multi-aggregated cauliflower-like structure. At higher concentrations, the NPs rearranged themselves in the shape of a hexagonal disk or a prism-like structure. The band gap values were found to decrease with increasing gelatin content and were in the range of 3.18–3.26 eV, though it showed the dependency on the size, shape and presence of C in ZnO. Studies of the dielectric properties and ac conductivity on the prepared NPs were also carried out.

Large size growth of Zinc(tris) thiourea sulphate (ZTS) crystals has been successfully done through slow solvent evaporation technique in presence of l-Ascorbic acid (LAA). The possibility of any extra phase due to presence of LAA was ruled out through structural analysis. The deviation in lattice parameters and shift in peaks position indicates the interaction of LAA with ZTS. Crystalline perfection of grown crystals was judged by High-resolution X-ray diffraction (HRXRD) study and found that the crystalline perfection of ZTS in presence of 10 wt% LAA is enhanced compared to others. The low optical absorbance and high band gap confirms its application in optoelectronic devices. A burly blue emission band at 460 nm was observed in Photoluminescence spectra of ZTS crystals grown in presence of LAA when excited at 310 and 358 nm both. However, when these specimens were excited at 385 nm this blue emission band is observed at 470 nm. The remarkable enhancement of blue band emission intensity was noted which may be attributed due to presence of defects (color centers). Further the dielectric measurement was done and shows that the dielectric constant has been improved due to presence of LAA. The enhanced optical band gap, photoluminescence intensity and dielectric constant suggests that the LAAZTS single crystals are suitable for electro-optic device applications. Keywords: Crystal growth, X-ray diffraction, HRXRD, Optical properties, Dielectric response

In this study, solvothermal method was used for the synthesis of MnFe₂O₄ nanoparticles at different processing period of 7, 14, and 21 h. X-ray diffraction (XRD) pattern study confirms that MnFe₂O₄ nanoparticles correspond to the face-centered cubic spinel structure and belong to the Fd3m [227] space group. From Raman spectra analysis, two major peaks were observed at 476 and 616 cm-1, which correspond to the vibration modes of MnFe₂O₄ nanoparticles; especially, the broad peak at 620 cm-1 (A1g) corresponds to the symmetric stretching vibration of oxygen atoms at tetrahedral site. Infrared spectra (FTIR) analysis at 490 and 572 cm-1 can be attributed to the stretching vibration of tetrahedral groups of FeO₄, and the vibration of octahedral groups of FeO6 belongs to the intrinsic vibrations of manganese ferrites. The uniformly distributed MnFe₂O₄ nanospheres (RT2) can be affirmed by field emission scanning electron microscopy images and confirmed by the high-resolution transmission electron microscopic studies. The electrochemical properties of synthesized MnFe₂O₄ nanoparticles investigated by cyclic voltammetry, impedance spectroscopy and galvanstatic charging and discharging (GCD) studies clearly predict the reversible faradaic reactions of MnFe₂O₄ nanospheres. Further, the MnFe₂O₄ nanospheres (RT2) exhibit high specific capacitance of 697 F g-1 at 0.5 A g-1 current density in galvanostatic charging and discharging profile and after 1000 cycles exhibits 79% retain ability of initial specific capacitance and hence can be considered as the efficient electrode for supercapacitor applications.

A transparent flexible polymer film is chemically functionalised with a bent-core liquid crystal (BCLC) compound for effective alignment of the bulk BCLC sample at the substrate–LC interface. The surface attachment was achieved via a simple procedure which involved pre-treatment of the polymer film (commercial name: over head projector film) using piranha solution followed by chemically attaching the BCLC compound through silane condensation reaction. Surface characterisation of the unmodified and BC-modified flexible films was carried out through X-ray photoelectron spectroscopy (XPS), attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy, contact angle (CA) and atomic force microscopy (AFM) techniques. The BC-modified flexible substrates are analysed for their efficiency to orient the bulk LC sample. Remarkably, the chemically modified polymer substrates are highly efficient in vertically aligning both the BC and rod-like LC samples at the substrate–LC interface, in comparison to their unmodified counterparts. The described method is simple, reproducible, surface modified substrates are highly stable and more importantly reusable. The demonstrated method for the alignment of BCLCs advances a step forward towards the realisation of applications proposed for these fascinating compounds.

The photoelectrical splitting of water is an important technique for the efficient generation of hydrogen using catalysts. However, understanding the effects of the size and crystallinity of catalysts is essential for tuning the efficiency of photo electrochemical hydrogen production. In this study, we synthesized WO3 nanocubes with controlled uniform size and shape using a low-temperature hydrothermal method at various temperatures. The nanocubes obtained at a calcinations temperature of 450 °C exhibited higher crystallinity and superior photo catalytic performance during the photo electrochemical production of hydrogen via the oxidation of water in KOH solution. The band gap was determined as ∼2.54 eV with a photocurrent density of 0.0021 mA/cm2 and a flat band potential around −0.77 V. The nanocubes also exhibited good stability in the alkaline KOH electrolyte for 2 h. Therefore, the superior crystallinity of the WO3 nanocubes could enhance the density of the charge carriers and improve the stability while also decreasing the band gap. These findings may facilitate the fabrication of a stable photo anode for large scale water splitting applications.

Neodymium doped zinc sulphide (Nd: ZnS) thin films were coated on glass substrates at 450 °C through low cost nebulizer spray pyrolysis (NSP) method. Structure, morphology, opto-electrical characteristics of Nd doped ZnS films with various Nd doping concentrations (0%, 1, %, 3% and 5%) were studied. X-ray diffraction patterns revealed that all coated films were polycrystalline hexagonal structure with (102) as a preferential direction. SEM images showed smooth and uniform spherical grains without any cracks and pinholes. Topological view by AFM described the increasing of roughness of the film through doping concentration. EDAX and Elemental mapping images confirmed the presence of Zn, S and Nd without any other impurities. Raman spectra reveals that E1(LO), 2TO, 2LO and 3LO emission modes with corresponding to the wave number. PL spectra showed high intense visible and broad UV emission band at 463 nm and 397 nm, respectively. Thickness of the films increased with Nd doping concentration reflecting the reduction of transparency of the films from 86% to 78% for 0% and 5% of Nd. UV–Vis Spectrum was used to study the energy gap (Eg), dielectric constant(e), refractive index(n), and extinction coefficient (k) of the prepared films. Four-point probe method was used to calculate the activation energy of Nd: ZnS thin films from the graph drawn between ln (ρ) and (1/T).

Er-doped CdO thin films are coated on FTO substrates using so-gel-spin coater technique. XRD studies confirm the polycrystalline nature of (111) orientation of the films. Crystallite size, dislocation density, and Lattice strain is calculated from XRD data and found that they are varying with doping percentage. AFM studies revealed homogeneous distributions of the nano-grains of 13–19 nm size. Energy dispersive spectroscopy and mapping analyses confirm the elemental composition. All the films are showing high transmission of nearly 80% in the visible spectrum. The calculated direct, indirect band gap values are changing with a variation of doping from 2.85 to 2.97 eV. At higher wavelength, the dielectric constant values are in the range of 20–80. The linear, third-order susceptibilities and nonlinear refractive index values are varying from 2 to 7, 1.6 × 10−13 to 5.41 × 10−13 esu and 1.39 × 10−12 to 8.1 × 10−11 esu respectively.

The flower like TiO2 nanoparticles have been identified as potential electrode material for efficient next generation electrochemical energy storage devices. The present work reports, a novel green approach to synthesize high surface area TiO2 nanoparticles using medicinal plant leaf extracts namely Ocimum Tenuiflorum Plant and Calotropis Gigantea Plant. The TiO2 nanoparticles synthesized using Calotropis Gigantea plant confirmed rutile phase from X-ray powder diffraction and Raman spectra. The fourier transform infrared spectroscopy spectra of the sample indicate the presence of TiO2 vibrational bonds. The field emission scanning electron microscopy images revealed that the flower like shape of nano-granules with an average granule size of 200 nm. The presence of Ti and O elements qualitatively confirmed using energy dispersive spectroscopy spectra, which shows the good stoichiometry in the sample. The flower like shapes with nano petals were further disclosed with the help of high resolution transmission electron microscopy. The corresponding optical band gap was observed to be 3.0 eV. The electrochemical investigations of the sample exhibited a high specific capacitance of 224 F g-1 at 0.5 A g-1 with 71% of capacitive retention after 5000 cycles.

Quercetin is well known for its effective inhibition of cancer cell proliferation by inducing the apoptosis. In the present study, quercetin isolated from Allium cepa were loaded on a biodegradable polymer, poly(lactic-co-glycolic acid) (PLGA) microspheres and its apoptotic potential in Michigan Cancer Foundation (MCF-7) cell was investigated. PLGA microspheres before and after loading indicated no significant difference in size as the average size of the microspheres were 100 μm. The encapsulation efficiency of quercetin on PLGA was found to be 74 ± 1.2%. Cytotoxicity and flow cytometric analysis were used to evaluate the capacity of quercetin-PLGA microspheres (PLGAq) on anticancer activity. PLGAq were assessed at two different concentrations (1.5 μg and 3.0 μg) and indicated that at higher concentrations it showed effective inhibition of cancer cells. The results indicated that the PLGAq microspheres efficiently inhibit cell proliferation by inducing the apoptosis demonstrating that the biodegradable PLGAq microspheres will provide a promising therapeutic approach for the treatment of breast cancer.

Undoped and rare earth Neodymium (Nd) doped cuprous oxide (Cu2O) thin films were prepared by electrodeposition method. The prepared film's structural, morphological, optical and photosensitive properties were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, ultra violet-visible and I-V measurements. The fabricated Cu2O:Nd films exhibited polycrystalline nature with cubic crystal system, and favorably grown along (111) orientation. Crystallite size was decreased from 56 nm to 30 nm with Nd concentrations. Raman spectrum confirmed the Cu2O phase of the prepared films. The morphological analysis showed pyramidal shaped particles for the undoped Cu2O thin film. The energy gap was reduced from 2.04 eV to 1.89 eV as Nd doping level was increased. From photoluminescence spectrum a high intense peak was observed at 619 nm which confirms the optical quality of Cu2O phase. The dielectric constant was increased by increasing the Nd doping concentration from 0 to 5%. In photosensitivity analysis an increase of photo response with respect to illuminated current was observed.

A simple, room-temperature approach for the synthesis of stable microparticles of copper in a lyotropic liquid crystal (LLC) template is described. The LLC phase having a hexagonal ordering is prepared using a mixture of non-ionic surfactant triton-X 100 and water in the ratio of 40:60 wt%. A controlled growth of copper particles is achieved in this medium by reducing cupric chloride using hydrazine hydrate under basic condition without the aid of any external stabilizing agent. Monodisperse, platelet-like copper microparticles (size ∼0.25 μm) are formed in this synthesis, which are well-dispersed in the lyotropic phase without aggregation. Besides, the copper particles are found to be stable for several months in the liquid crystalline medium. The LLC medium directed the growth of anisotropic microparticles and also acted as a stabilising agent. These micro platelets of copper are found to exhibit significant catalytic and electrocatalytic activity for the sodium borohydride mediated conversion of 4-nitrophenol to 4-aminophenol and for the reduction of hydrogen peroxide respectively.

La-doped SnO2 thin films (1, 2.5, 5.0, 7.5 and 10%) have been coated on FTO substrates by a sol-gel spin coating technique. XRD studies confirms the (100) orientation of all prepared films of polycrystalline nature. Vibrational modes confirm the fabrication of single phase SnO2 films. EDX/SEM mapping confirms the presence of La in SnO2 films. AFM reveals the grain size in range of 17–82 nm along with RMS roughness in 13 and 38 nm. The direct band gap values of pure and La doped SnO2 thin films are varying between 4.15 and 3.95 eV. The refractive index (n) and absorption index (k) values were found to be reducing below 5% La doping and showed an increasing tendency beyond 5% doping. Further, the investigated values ( χ 1 ) , ( χ 3 ) and n 2 were found in the range of 0.032–47, 1.5 × 10−8 to 8 × 10−4 esu and 2.3 × 10−7 to 1.2 × 10−3, respectively.

In the current work, the authors studied a hybrid organic-inorganic photodiode combining n-type monocrystalline silicon (n-Si) and indigo dye where the natural dye indigo has been applied as an interfacial layer between Gold (Au) and n-Si. The electrical and photo-response characteristics of photodiode based on indigo dye were investigated through current, conductance and capacitance studies measured under the wide illumination intensity and frequency ranges. The frequency dependency of capacitance-voltage (C-V) and conductance-voltage (G-V) characteristic properties of the Au/Indigo/n-Si photodiode was examined in the frequencies varying from 100 kHz to 1 MHz in view of the effects of series resistance (Rs), the concentration of donor atoms (Nd) and density of interface states (Nss). The C-V and G -V studies indicate that the Nss and Rs are key factors which are strongly influencing the electrical properties of the fabricated Photodiode. From the obtained results, the fabricated Au/Indigo/n-Si photodiode can be a promising contender for electro-optic device engineering.

The SnO2 nanoparticles formation by hydrothermal method at different experimental conditions such as temperature, pH, reaction time, and capping agent (cetyltrimethylammonium bromide), was studied. X-ray diffraction results confirmed regular rutile crystal structure of SnO2. The characteristic Raman peak observed at 635 cm−1 corresponded to A1g modes of Sn–O vibrations. The study of optical property using photoluminescence confirmed the emissive spectra of SnO2. The infrared peak observed at 618 cm−1 corresponded to Eu modes of Sn–O vibrations of TO phonon because of E⊥ to c-axis. Scanning electron microscope images clearly revealed the formation of complete SnO2 nanoparticles. The unique SnO2 nanoparticles stacked together to form microspheres at pH-5 showed high specific capacitance of 274.8 F/g at a current density of 0.5 A/g. The observed results confirmed the feasibility of SnO2 nanoparticles being used as appropriate positive electrode candidate for supercapacitor applications.

In this study, Fe-, Ce-, and La-doped TiO2 ultrafine nanospheres were synthesized via low-temperature solvothermal method. The structural and morphological variations of bare and M (Fe, Ce, La)- doped TiO2 were confirmed by X-ray photoelectron spectroscopy and transmission electron microscopy images. The fabricated photoanodes were tested using 1 M KOH electrolyte and demonstrated that they can be used for eco-friendly photoelectrochemical solar water-splitting application. Compared to bare TiO2 photoanodes, foreign cations (Fe, Ce, La)-doped TiO2-based photoanodes exhibited higher photocurrent response without bias. In nutshell, the rare-earth element La-doped TiO2 nanosphere photoanode showed good photocurrent response to approximately 0.48 mA/cm2 under illumination, with lower flat band potential shift of −0.83 V. The highest photostability of 96% was achieved over 2 h for 10% La-doped TiO2 nanosphere photoanode and was suitable for solar water-splitting applications.

Synthesis of pure and 0.1 to 5 wt.% Gd-doped CdS nanoparticles (NPs) was achieved through a modified domestic microwave-assisted route in a short timespan at 700 W power. The formation of hexagonal CdS NPs was verified via X-ray diffraction analysis, and no structural variation was observed except for lattice variation. The size of the crystallites (D), dislocation concentration, and lattice strain were calculated, and the D was in the range of 3–6 nm. Fourier transform-Raman analysis confirmed the presence of 1LO, 2LO, and 3LO modes at 294.76, 590, and 890 cm−1, respectively, in all the synthesized nanostructures, with minute variations in their positions due to doping; however, no new mode was observed. The position of the vibration modes was red shifted compared to that of the bulk material, indicating a confinement effect. Scanning electron microscopy (SEM) mapping/energy-dispersive X-ray spectroscopy revealed homogeneous doping of Gd and the presence of all the constituents in the final products. The morphology of the synthesized materials was tested via field-emission SEM, which revealed spherical NPs with small dimensions. Additionally, high-resolution transmission electron microscopy was performed to visualize the shape and size of the prepared 0.1% Gd:CdS NPs. The energy gap was calculated using the Kubelka–Munk theory and found to be in the range of 2.31–2.41 eV. The photoluminescence emission spectra exhibited two green emission peaks at 516 ± 2 nm and 555 ± 2 nm and showed the reduction of defects with Gd doping in terms of intensity quenching. The dielectric constant ( e ' ), loss, and alternating-current electrical properties were studied in the high-frequency range. The values of e ' were in the range of 17–27. An enhancement of these values was observed for CdS when it was doped with Gd. The electrical conductivity exhibited frequency power law behavior.

Organic electrode materials have high capacity, and environmentally friendly advantages for the next generation lithium-ion batteries (LIBs). However, organic electrode materials face many challenges, such as low reduction potential as cathode materials or high reduction potential as anode materials. Here, the influence of chemical functionalities that are capable of either electron donating or electron withdrawing groups on the reduction potential and charge-discharge performance of anthraquinone (AQ) based system is studied. The cyclic voltammetry results show that the introduction of two —OH groups, two —NO2 groups and one—CH3 group on anthraquinone structure has a little impact on the reduction potential, which is found to be 2.1 V. But when three or four—OH groups are introduced on AQ structure, the reduction potential is increased to about 3.1 V. The charge-discharge tests show that these materials exhibit moderate cycling stability.

Transparent conductive oxides (TCOs) are having emerging applications in optoelectronic technology. Hence, herein, we have designed and fabricated the cadmium oxide (CdO/FTO) TCO films with different concentrations of Lanthanum (La) through a facile spin coating technique. The crystal system and phase confirmation of fabricated films was analyzed by X-ray diffraction analysis. The values of D 200 are found in the range of 25–31 nm indicates nanostructured thin films fabrication. EDX/SEM mapping revealed the presence of La and its homogeneity in CdO film. Atomic force microscopy was carried out to investigate the effect of La doping on surface topography of CdO films. The average values of grain size were estimated in the range of 7.56–10.95 nm along with surface roughness in range of 15.25–17.56 for pure and La-doped CdO films. The optical transparency of films was noticed in range of 75–85% in the NIR region. Direct and indirect band gap values are found in the range of 2.55–2.8 eV and 2.0–2.4 eV, respectively. The dielectric constant, loss, refractive and absorption indices were also calculated. Moreover, the linear, nonlinear susceptibilities and refractive index values were estimated and found in the range of 0.1–3, 1 × 10−12 to 1.6 × 10−7 esu and 2 × 10−12 to 1.28 × 10−8 esu, correspondingly.

NiO has been found to have excellent physical properties which are crucial for several significant electro-optical devices. Herein, we have designed and fabricated high-quality films of NiO with various concentrations of Ce and studied their key properties. X-ray diffraction (XRD) study confirmed the cubic phase, good crystallinity and growth direction along (111) plane in the prepared samples. The crystallite size was noticed in the range of 13–30 nm. For confirming the presence of Ce doping and its homogeneity in NiO films the EDX/SEM mapping was carried out. AFM study provided the topographic information in terms of size of the grains and roughness of all films. The grown films were found to be 70–80% optically transparent in the whole testing region. Optical energy gap was found to expand from 3.60 to 3.68 eV owing to Ce-doping. The refractive index value was noticed to be in the range from 1.7 to 2.7. The n2 and χ ( 3 ) values for pure and Ce-doped NiO films varied from 2 × 10−10 to 1.4 × 10−11 and 1 × 10−12 to 1.1 × 10−11 esu, respectively. Obtained results indicated that Ce has strong influence on opto-nonlinear characteristics of NiO films and proposed their application in the opto-nonlinear devices.

The present work addresses the important need of new materials to improve energy storage materials. The synthesis of MnCo2O4 nanospheres by employing solvothermal method at different incubation times was carried out. The effects of reaction time on structural, morphological, and electrochemical studies were briefly investigated. The X-ray diffraction result unveils the formation of cubic-structured MnCo2O4 nanospheres with Fd3m (2 2 7) space group. The appearance of two Raman peaks at 480 and 662 cm−1 was greatly attributed to the stretching vibration mode of M–O (M = Mn, Co), and substantiates the formation of MnCo2O4. The presence of functional group and characteristics group was analyzed by Fourier-transform infrared spectroscopy. The scanning electron microscope image clearly indicated different sizes of nanoparticles due to the effect of solvothermal reaction period. The energy storage behavior of MnCo2O4 nanospheres was studied by employing the cyclic voltammetric and charge–discharge cycles. The results confirmed the pseudocapacitive nature of MnCo2O4 nanoparticles (RF3) with porous, spherical nanostructure with larger radius than others and contribute to better specific capacitance of 252 F g−1 at current density of 1 A g−1 which could be considered as a potential candidate for pseudocapacitive electrode for energy storage devices. Keywords: Cubic, MnCo2O4, Nanospheres, PVP, Fd3m (2 2 7) space group, Energy storage

Highly stable Rose Bengal (RsB) organic semiconductor thin films were deposited on glass substrates with different thicknesses ranging from 95 to 325 nm. Optical transmission, reflection, and absorption studies were employed to analyze various optical constants. Refractive index and extinction coefficient values were attained using Kramers-Kronig calculations from the reflectance data. Dielectric constant, loss and dissipation factor were studied. Third-order nonlinear optical susceptibility and refractive index values were estimated using linear refractive index and absorption coefficient data for RsB films and studied their properties in nonlinear media. Optical limiting characteristics are found to be enhanced by increasing the thicknesses of films. The studied films can be used to limit the laser power of wavelengths 632 nm and 532 nm as an optical limiting material. The present work suggests that film of RsB is a promising candidate for wide-scale optoelectronic applications including IR pass filter, laser power attenuation, and selective CUT-OFF laser filters in the wavelength range 490–595 nm.

Synthesis of polyoxometalates (Cu3Mo2O9 nanopowders) was obtained by using solvothermal method and confirmed by X-ray diffraction pattern, with orthorhombic crystalline structure belonging to the space group Pna21(33). Further, the synthesized Cu3Mo2O9 nanopowders were analyzed by using Raman, infrared, and photoluminescence studies. X-ray photoelectron spectroscopy study explained the oxidation states of Mo-3d, Cu-2p, and O-1s in Cu3Mo2O9 nanopowders. Field emission scanning electron microscopy images clearly revealed the formation of nanostructure randomly oriented to form an interconnected rout, which emerged as a good candidate for storing more charges at the surface of Cu3Mo2O9 nanopowders. The electrochemical studies, such as cyclic voltammetry, electro impedance analysis, and galvanostatic charging–discharging studies, were used to analyze its electrochemical properties. To ensure the stability of Cu3Mo2O9 nanopowders, continuous charging and discharging studies were conducted for 1000 cycles at a current density of 5 A g−1 and it exhibited good stability over a large number of cyclic studies with capacity retention of 99.2% after the first 500 cycles.

Recently there has been immense interest in the exploration of richly available two-dimensional non-toxic layered material such as tin disulfide (SnS2) for potential employment in energy and environmental needs. In this regard, we report on the synthesis of few-layered Sn1−xMgxS2 nanosheets through a facile one-step hydrothermal route to address all such functions concerning photocatalysis and photoelectrochemical conversion. The crystalline order and structure of processed layered Sn1−xMgxS2 were initially found to exhibit a strong influence on their physicochemical properties. Their optical properties attest the Mg doping in SnS2 to benefit us with enhanced visible-light absorption via red-shift in their absorption edge. In the photoluminescence spectrum the emissions observed along visible and red region signifies the association of Mg related trap states in Sn1−xMgxS2. Next, the photocurrent and electrochemical impedance spectroscopic results revealed the Mg doping to promote the effective charge transfer process (which was beneficial to enhance their photocatalytic activity). Consequently, the layered Sn0.98Mg0.02S2 made photoanodes displayed 1.7 fold higher photocurrent density under simulated solar radiation with respect to their undoped counterpart. Furthermore, the layered Sn0.98Mg0.02S2 nanosheets exhibits enhanced visible light decomposition of organic dye while compared with pristine SnS2 nanosheets. The value of rate constants obtained for the Sn0.98Mg0.02S2 nanosheets was found to be 1.4 times higher than that of pristine SnS2. Finally, the results obtained through the present study projects the huge potential of layered Sn0.98Mg0.02S2 nanosheets for future multifunctional applications.

In present work, bulk size (∼5 cm in length and 2 cm in dia.) single crystal of glycine zinc sulfate (GZS) was harvested from Sanakaranarayan - Ramasamy (SR) technique. The harvested crystal was exposed to in-depth study of its physical properties such as: optical, nonlinear and mechanical. Moreover, the DFT is also applied to study the molecular geometry, optical and nonlinear characteristics. XRD study confirms the formation of GZS crystal which was further confirmed through vibrational analysis. Optical absorbance and transmittance measurements were carried out. The grown crystal was found to be ∼80% transparent in wavelength from 300 to 950 nm and the band gap was estimated to be ∼4.6 eV. The respective μtot and βtot values are obtained about 3.6 times and 15 times larger compared to urea which confirm the application of GZS in NLO devices. The robust chemical etching and mechanical properties has been studied by applying different models.

A new ionic liquid crystal (ILC) containing cholesterol and bearing a terminal imidazolium moiety was synthesised and its mesophase behaviour was investigated by polarising optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. The ILC displayed an intercalated lamellar mesophase having a wide phase range. Cyclic voltammetry studies of the synthesised ILC revealed electrochemical stability with a good electrochemical window. Further, the electrochemical performance of the ILC was evaluated as an electrolyte (0.5% in ethanol) for supercapacitor applications using a three electrode system consisting of a graphene oxide–manganese dioxide (100 μm) coated carbon fiber electrode, silver–silver chloride (Ag–AgCl) reference and platinum foil counter electrodes. Among three different ratios of graphene oxide–manganese dioxide (1 : 1, 1 : 0.5, and 0.5 : 1) investigated, the electrode containing 0.5 : 1 wt% graphene oxide–manganese dioxide over carbon fiber showed good capacitive behaviour with a specific capacitance of 157.5 F g−1 at a constant current density of 0.5 A g−1 along with a good cyclic stability. In addition, the ILC was also studied as an electrode material in combination with carbon paste for investigating electron transfer reactions.

In this work, nanostructured methyl violet-10B (MV-10B) thin films of various thicknesses were coated on glass substrates by a low-cost spin coating method at different rpm. The structural analysis of nanostructured MV-10B thin films was carried out by X-ray diffraction and atomic force microscope. Optical measurements were carried out, and the direct band gap of MV-10B films was estimated. The study showed that the prepared MV-10B thin films act in the same manner as that of conventional direct bandgap semiconductors. From optical studies, the sample exhibited bandpass filter characteristics in IR range from 700 nm to 900 nm and in the visible range centered around 408 nm. Also, the sample absorbs or attenuates the range of wavelengths in the visible spectrum between 470 and 650 nm creating a good absorption band valley making a CUT-OFF laser filter. Optical constants such as refractive index (n) and extinction coefficient (k) were computed using Kramers–Kronig relations. The real and imaginary components of dielectric constant were calculated on the basis of polarization of light when it is impinging on semiconductors. Nonlinear index of refraction and susceptibilities were estimated by linear refractive index dispersion principles. Optical limiting studies showed that the MV-10B thin films are very good optical limiters even at low thickness. The MV-10B showed a laser attenuation behavior for He-Ne and green lasers. The obtained results suggest that the newly designed thin films are the promising candidate in different applications.

Herein, we report samarium (Sm) dopant concentration effect on Cu2O films characteristics prepared by electrodeposition method. XRD patterns of the films indicated that pristine and Sm:Cu2O films have polycrystalline cubic structure with (111) preferred orientation. It was seen from the SEM photographs pinhole free dense triangle shaped grains for undoped Cu2O thin films and the grain size was decreased as concentration of samarium was increased. Raman spectroscopy showed peaks at 108, 146, 217, 413 and 637 cm−1 which conformed the Cu2O phase formation and intensity of the peaks was decreased with a increase in dopant concentration. UV–Vis spectra exhibited that the absorption value of Cu2O films is increased gradually with reduction in band gap value for the increase of samarium content. Photoluminescence (PL) spectra revealed that all films display a visible light emissions and its intensity was reduced due to increase in doping concentration. Photosensitivity observation study indicated that the photocurrent of deposited Cu2O films was increased along with the increase in dopant material concentration.

Pure and Ag doped CdS nanocrystalline films with different Ag doping concentrations were successfully grown on glass substrates by a sol-gel spin coating method. Ag doping was performed using silver acetate aqueous solution with 0.01, 0.02 and 0.03 M concentrations via ion exchange. The influences of Ag doping on structural, vibrational, morphological, linear and third order nonlinear optical properties of CdS nanocrystalline films were studied. The x-ray diffraction patterns of the films exhibited a broad peak centered at an angle 2θ = 26.5° along the (111) plane, which confirms the cubic structure and formation of nanocrystalline films. Raman spectra of films demonstrate a shift in longitudinal optical phonon vibrations as compared to the bulk counterpart. Pure CdS film shows high transmittance (83%) in the visible and near infrared (NIR) regions. With Ag doping, a significant red shift in the band edge and reduction in the transmittance of the films in visible and NIR regions were observed. However, the films doped with Ag showed appreciable transmittance in visible region for window layer applications. A significant effect on optical parameters such as absorption index, refractive index, and optical dielectric constant was observed after Ag doping. The nonlinear optical properties of films were enhanced with incorporation of Ag atoms into the CdS binary system. The values of nonlinear optical susceptibility χ(3) and refractive index n2 were found to increase with increasing Ag concentration and were estimated to be in the range of 2.92 × 10−10 − 1×10−7esu and 1.00 × 10−9 − 2.00 × 10−7esu, respectively. These values suggest that these films can be potential candidates for nonlinear optical device applications.

In this study, we investigated the monocrystal growth and characteristics of pure and methyl violet (MV) dyed zinc(tris) thiourea sulfate (ZTS) large size single crystals. The morphology of ZTS was modified in the presence of MV dye. The crystals were crushed for a finite time to obtain powders for X-ray diffraction analysis and the lattice parameters were determined. The crystals were analyzed based on Fourier transform-Raman spectroscopy measurements and the vibrational modes were identified. Some extra vibrational modes were observed due to the presence of the MV dye. Ultraviolet–visible–near infrared optical absorbance measurements were recorded and the band gap was calculated. A large band gap ∼4.31 eV was obtained for the ZTS crystals, which supports their possible application in electro-optic devices. Two absorption bands at around 584 nm (sharp) and ∼362 nm (broad) were also observed in the dyed crystals but not in the pure crystals, thereby indicating the interaction between the dye and ZTS. Photoluminescence (PL) emission studies were conducted at an excitation wavelength of 360 nm. PL emission peaks were observed at ∼433 nm in the pure crystals, and at ∼421 and 444 ± 5 nm in the dyed crystals. Differential scanning calorimetry demonstrated the increased melting temperature of ZTS in the presence of the dye. The dielectric constant, ac electrical conductivity, and mechanical strength were higher for the dyed crystals. Our results suggest that the dyed crystals may be more suitable for applications in opto-electronic devices compared with the pure crystals.

In the present work, pure and dysprosium (Dy) doped SnO2 films have been fabricated through sol-gel spin coating technique. Strong influence of Dy doping is observed on structural, morphological, vibrational, linear and nonlinear optical properties of SnO2 films. X-ray diffraction study revealed that deposited films exhibit tetragonal crystal structure with preferentially grown along (2 0 0) plane. With increase of doping concentration in SnO2, the crystallite size decreases while dislocation density and lattice distortion ratio increases. The characteristics Raman peaks of doped SnO2 thin films broaden, shifted and intensity decreases as compared to pure film which confirm the bonding between Dy and SnO2. Optical study shows that the prepared thin films are highly transparent and absorption increases with doping concentrations owing to increase of defects states. It is also observed that the optical band gap first increases and then lessens with rise of Dy-doping concentration which attributed to the Burstein-Moss (BM) effect. Additionally, dielectric constant and refractive index first decreasing with small doping concentration (1–3%) due to increase of carrier concentration, and then increases for higher doping (5–7%) due to increase of defect in SnO2 lattice. The values χ 3 and β obtained by Z-scan measurement are observed in range of 0.31 × 10−7 to 1.28 × 10−7 and 1.27 to 5.32 × 10−4 cm W−1, respectively. The limiting threshold of pure and Dy doped SnO2 nanostructured films were calculated to be in the range of 5.37–11.18 kJ/cm2.

Nanostructured thin films of pure as well as Mg-doped Zinc Oxide (MZO) were successfully casted on glass substrates through sol-gel technique. X-ray diffraction patterns display that all deposited films exhibit good crystallinity, hexagonal wurtzite structure and are preferentially grown along (002) plane (i.e. C-axis). Surface morphology, vibrational modes and optical properties were inspected by AFM, FT-Raman and UV–Visible–NIR spectroscopy. AFM Analysis revealed the uniform nanowire growth of MZO films where each nanowire was made up of very fine nanoparticles. The grain size was found to be increased from 16 to 25 nm with increasing the Mg-doping which agreed with the crystallite sizes obtained from the XRD analysis. The linear and nonlinear optical functionals were evaluated from optical data. Further, the deposited films were subjected to Z-scan measurement and studied its different key properties. The values of χ ( 3 ) is found to be enhanced from 0.27 × 10−8 to 4.36 × 10−8 due to Mg doping. The optical limiting threshold of MZO nanostructured films are also studied, and the obtained threshold values are found in the range 1.7 to 7.4 kJ/cm2. These low values suggests that the fabricated films can be used as optical limiters to protect sensor devices from high intensity light.

The present work deals with the deposition of NiO and Nitrogen (N)-doped NiO thin films by sol-gel spin coating technique. Structural, morphological, linear and non-linear optical characteristics of undoped and N-doped (1–15 wt%) NiO films were studied. From XRD measurements, it is evident that single phase nano crystalline NiO is formed for all doping concentrations. Surface morphology study shows that higher concentration of N doped NiO thin films were of high quality and EDX mapping confirmed the doping of Nitrogen in films. The Raman spectra of the studied films were analyzed over the range of 1400-200 cm−1. The optical studies confirm that as doping increases, transparency of the film decreases (except at 10% N doping) and the band gap narrows. Nonlinear parameters such as refractive index and susceptibilities also depend on N dopant concentration. Z-scan studies viz., absorption index, nonlinear refractive index were carried out on undoped and N doped NiO samples and the results were matched with theoretical calculated values.

Metals and metal oxide-based nanocomposites play a significant role over the control of microbes. In this study, antibacterial activity of iron oxide (Fe2O3) nanocomposites based on induction furnace (IF) steel slag has been carried out. IF steel slag is an industrial by-product generated from secondary steel manufacturing process and has various metal oxides which includes Al2O3 (7.89%), MnO (5.06), CaO (1.49%) and specifically Fe2O3 (14.30%) in higher content along with metalloid SiO2 (66.42). Antibacterial activity of iron oxide nanocomposites has been revealed on bacterial species such as Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus. Micrococcus luteus has undergone maximum zone of inhibition (ZOI) of 12 mm for 10 mg/mL concentration of steel slag iron oxide nanocomposite. Growth inhibitory kinetics of bacterial species has been studied using ELISA microplate reader at 660 nm by varying the concentration of steel slag iron oxide nanocomposites. The results illustrate that IF steel slag is a potential material and can be utilized in building materials to increase the resistance against biodeterioration. Graphic abstract

The changes in power quality are very quick and a difficult task to know under power networks. Most of the power quality issues are observed in interconnected networks due to different sources of power generation can be attributed to temporary faults and sudden loading conditions. The Flexible AC Transmission Systems (FACTS) provide one of the fastest controls of reactive and active power through a multi bus system. The Static Var Compensator (SVC) is one of the FACTS controllers with reasonably good features. Operating with multi terminal systems, when incorporating with FACTS devices are very complex in power systems which needs effective and detailed study, particularly for fault identification. The present research work explores the analysis of wavelet multiresolution with the usage of the mother wavelet Bior1.5 for different Power Quality problems are presented to evaluate the analysis of a 5-bus network. In this work different power quality issues are tested during different faulty conditions and when sudden load of 50 MW injecting in to the line conditions and the performance and effectiveness is analysed in the environment of SVC. The effectiveness of wavelets is useful to find out the fault in under different fault conditions as well as under sudden loading conditions.

The undoped and terbium (Tb)-doped SnO2 thin films are coated on the glass substrates using the nebulized spray pyrolysis (NSP) technique. The crystallite size is calculated using the Williamson-Hall method and is found to be decreased from 80 to 56 nm with the increase of Tb doping concentration. Atomic force microscope (AFM) images show the spheroidal shape of the grains. The elemental analysis of the samples was investigated by energy dispersive analysis of X-rays (EDX). An increase in absorbance and decrease in bandgap values provide more photon absorption which enhances the photocatalytic reaction. The PL studies reveal the creation of more defect levels by doping which provides more active sites for catalyzed reactions. The Tb doping with SnO2 improved the rate constant about 0.015/min, and a maximum photocatalytic dye degradation efficiency of 85% against methylene blue dye was observed. Therefore, the fabricated films found potential applications for photocatalysis that enable them to chemical industries.

This work reports the changes in the properties of Ag-doped SnS thin films (SnS:Ag), and CdS/SnS solar cells with an Ag dopant concentration in the absorber varied from 0 to 6 wt.% in steps of 3 wt.% prepared by the nebulizer-assisted spray pyrolysis method (NSP). X-ray diffraction (XRD) studies confirm the SnS:Ag (3 wt.%) thin film has a higher crystallite size than the undoped and SnS:Ag (6 wt.%) thin film. An atomic force microscope (AFM) image shows SnS:Ag (3 wt.%) film possesses larger-sized grains than other samples. The energy-dispersive X-ray analysis (EDS) confirms the presence of the constituent elements in the SnS:Ag thin films. PL analysis revealed the films possess the band edge as well as the other defect-related emissions of SnS. The Ag doping facilitates the tunability in absorption and decreases in optical bandgap for the SnS:Ag (3 wt.%) film. Hall measurements provide the low resistivity of 3.31 Ωcm, the high charge carrier concentration of 1.56 × 1017 cm−3, and high mobility of 12.1 cm2 V−1 s−1 for 3 wt.% Ag-doped SnS film. The better photovoltaic conversion efficiency of 0.285% was observed for the device prepared with SnS:Ag (3 wt.%) thin film compared to other samples due to enhanced absorption, optimum bandgap, and better electrical properties.

Sol–gel-assisted spin coating technique has been employed to deposit Ce-doped cadmium oxide films (CdO) thin films on a glass substrate. Structural analysis carried out by XRD revealed that the films are polycrystalline and crystallize in a cubic structure. The preferential directions for the CdO growth are (2 0 0), and (2 1 0) and doping of Ce ions inhibits the growth. In addition to XRD, Raman analysis also supports the crystalline phase with no impurities. Using the Kramers–Kronig relations, the dispersion relation is evaluated from which the refractive index and the absorption coefficient were derived. The deposited doped and pure CdO films are highly transparent. The energy gap values of pure and doped CdO films are in the range of 2.2–4.2 eV, making them suitable for optoelectronic applications. The lower values of ‘n’ and ‘k’ are making the films most significant. The dielectric constant and nonlinear optical properties showed an increasing tendency on doping Ce ions into CdO films.

Novel nebulizer spray pyrolysis method was used to prepare erbium (Er) and fluorine co-doped tin oxide (FTO) films with doping concentration (0.5, 1, 1.5 wt.%). The effect of Er on FTO were analyzed by various characterization tools. XRD studies revealed tetragonal crystal structure with polycrystalline nature and crystallize size decreasing with Er concentration. AFM studies confirmed the smoothness of the films. Photoluminescence study revealed the emission peaks in UV and visible region. Transmittance, carrier concentration and carrier mobility are more in case of 1.5 wt.% doping concentration confirms the prepared films are opting for optoelectronic devices.