Sulfide Thin Films Research Articles

Transforming energy and water landscapes with MnS2:Ni9S8:Co3S4: A promising paradigm for a sustainable future

AbstractBackgroundConsiderable research efforts have been dedicated to comprehensively evaluate the electrochemical and photocatalytic properties of newly synthesized metal sulfides.AimsThis research aims to determine the viability of using metal sulfide, MnS2:Ni9S8:Co3S4 thin film with excellent energy retention capacities and amazing photocatalytic activities.Materials & MethodsSingle source precursor method was utilized for the synthesis of metal sulfide. Furthermore, deposition of thin film was performed through physical vapour deposition route. Detailed characterization was done by using UV‐visible spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction crystallography and X‐ray photoelectron spectroscopy. Electrochemical investigation was done through cyclic and linear sweep voltammetry while competence of the thin film in degrading various environmental pollutants, including crystal violet dye, fuberidazole and phenol, was evaluated by photocatalytic degradation.Results & DiscussionA crystallite size of 47 nm with 86.5% crystallinity was found along with a 3.4 eV bandgap energy. Round‐edged cubical structures in the composite were seen. X‐ray photoelectron spectroscopy revealed core level peaks of Mn 2p, Ni 2p, Co 2p and S 2p. A specific capacitance of 590 Fg−1 was observed from the electrochemical analysis showing the presence of electroactive sites that allow for effective electrochemical processes. After 60 minutes of exposure to the thin film, phenol showed the slowest rate of degradation, whereas crystal violet and fuberidazole showed significant percentages of deterioration.ConclusionThe findings highlight MnS2:Ni9S8:Co3S4 thin film's adaptability as viable compound for addressing the critical concerns of storing energy, production, and environmental cleanup. These significant findings highlight the versatility of tri‐metal sulfide thin films, opening up avenues for further research and technological advancements.

Advancing energy and water solutions: Unleashing the potential of Nd2S3:Ni9S8 thin film for supercapacitors and sustainable water purification

AbstractThe research was done on the creation and use of bi‐metal sulfide thin film, Nd2S3:Ni9S8. 41 nm‐sized crystallites with 80% crystallinity were found in the material. The evaluated optical characteristics showed a 2.9 eV band gap energy. The presence of Nd3d, S2p, and Ni2p in the created material was confirmed by X‐ray photoelectron spectroscopy. Voltammetry tests were carried out to assess the electrochemical characteristics. With a value of 750 Fg−1, the findings obtained showed remarkable supercapacitive capability. Additionally, a thorough examination was done to learn more about the material's potential as a photocatalyst. Malachite green dye, fuberidazole, and phenol were used as environmental contaminants to test the thin films' photocatalytic degradation effectiveness. The highest degradation was found for fuberidazole with a rate constant of 2.46x10−2 min−1. The results demonstrated the versatility of thin films and their efficacy in degrading these pollutants, highlighting their potential for environmental remediation applications.

Carbon Nanodots as Complexing Agent in the Formation of Lead(II) Sulfide Thin Films via Direct Deposition of Lead(II) Sulfide Powder

This study reveals for the first time the formation of lead(II) sulfide (PbS) thin films via direct deposition of PbS powder using carbon nanodots (Cdots) as a complexing agent. The chemical bath deposition (CBD) technique was utilized and the Cdots’ mass was varied, i.e., (in g) 3, 5, 7, and 9. The Cdots were prepared from the waste of a rice noodle production home industry via the low-temperature carbonization method. The Cdots were characterized using UV-Vis spectrophotometry, showing absorption peaks at 275 nm and 325 nm; PL, showing an emission peak at 500 nm with cyan luminescence; XRD, showing several peaks, indicating an incomplete carbonization process; FTIR, indicating the existence of C=C, C-H, C-O, and O-H functional groups; HRTEM, revealing the sizes of the Cdots in the range of 2 nm to 6 nm; and SEM, showing a smooth morphology of the Cdots’ surface. The thin films obtained were smooth with higher XRD peaks and better material distribution compared to pure PbS thin film. The band gap measurement indicated that the increase of the PbS band gap was caused by the increase of the Cdots’ mass. Hence, the thin films’ band gap may be tuned using the Cdots’ mass.

Biological approach synthesis and characterization of iron sulfide (FeS) thin films from banana peel extract for contamination of environmental remediation

Biological approach synthesis and characterization of Iron Sulfide (FeS) thin films from banana peel extract for contamination remediation of environment studied. Iron chloride, Sodium thiosulfate and Ethylene-di-amine-tetra acetate (EDTA) were used as precursor solutions without further purification. The nanoparticle of banana peel was extracted and prepared with synthesized FeS thin films and analyzed by X ray-diffraction for structural examination, Scanning electron microscope (SEM) for surface morphological analysis, Ultra-violet-visible-spectrometer (UV–Vis) and photo-luminescence spectro-photo-meter (P-L) for optical characterizations. XRD peaks are shown with recognized to (110), (200), (310), and (301) crystalline planes. The occurrence of this deflection peak are recognised the FeS crystal segment of the tetragonal crystalline systems. SEM micrographs of the films prepared biological method show the distribution of grains, which cover the surface of the substrate completely and are uniform and films deposited purely have defects. The photo-luminescence, absorbance, and transmittance strength of banana peel extract FeS thin film is greater than pure FeS thin films in which wide-ranging and symmetries groups were perceived. In the present study, the comparison of pure FeS thin films and Nano synthesized banana peel extract with FeS thin films was studied. It is observed that Nano synthesized banana fibre absorbs higher than pure FeS thin films in solar cell application. Finally, green synthesis is an ecofriendly, easy and cheap promising method for the fabrication of thin films for solar cell applications.

Influence of Substrate Temperature on Structural and Optical Properties of Co-Evaporated Cu<sub>2</sub>SnS<sub>3</sub>/ITO Thin Films

In this study report the structural and optical properties of Copper Tin Sulfide (Cu2SnS3) thin films on indium tin oxide (ITO) substrate using co-evaporation technique. High purity of copper, tin and sulfur were taken as source materials to deposit Cu2SnS3 (CTS) thin films at different substrate temperatures (200-350 °C). Further, the effect of different substrate temperature on the crystallographic, morphological and optical properties of CTS thin films was investigated. The deposited CTS thin films shows tetragonal phase with preferential orientation along (112) plane confirmed by X-ray diffraction. Micro-Raman studies reveled the formation of CTS thin films. The surface morphology, average grain size and rms values of the deposited films are examined by Scanning electron spectroscopy (SEM) and Atomic Force Microscopy (AFM). The Energy dispersive spectroscopy (EDS) shows the presence of copper, tin and sulfur with a nearly stoichiometric ratio. The optical band gap (1.76-1.63 eV) and absorption coefficient (~105 cm-1) of the films was calculated by using UV-Vis-NIR spectroscopy. The values of refractive index, extinction coefficient and permittivity of the deposited films were calculated from the optical transmittance data.

Structural and Optical Properties of Chemically Deposited Metal Chalcogenide Thin Film CrS and its Photovoltaic Application

In this work, chromium sulfide (CrS) thin films were grown on the acetic acid substrates by chemical bath deposition to prepare non-toxic photovoltaic devices. The combined single-source precursor approach has been developed for the deposition method using tris(diethyldithiocarbamato)chromium(III) for the deposition of CrS thin films grown at bath temperatures of 30, 60 and 90 ºC and at a constant deposition time of 30-120 min. The sufrace mophology of the prepared films have been analyzed by SEM and HR-TEM techniques. The study of the films indicate the distributed roughness and nano bundled hexagonal structures. The energy dispersive X-ray (EDX) spectroscopy analysis conformed the presence of Cr and S. The polycrystalline behaviour of the films was studied by an XRD study which revealed the mixed phases with a predicted crystallite size of 20 nm. The optical measurements showed films had a maximum transmittance of 90% in the visible region and the evaluated energy band varied in the range of 2.2-2.378 eV with the change of bath temperatures. This suggests that CrS thin film prepared at 90 ºC has enhanced crystalline superiority. According to photoluminescence (PL) analysis, the green emission can be attributed to the presence of several deep trap states or defects in the CrS structure. Moreover, natural dye sensitized solar cells (DSSCs) in CrS thin film prepared at 90 ºC, Jsc (28.0 mA/cm2) produced a larger voltage in the short circuit as compared to synthetic dye sensitized solar cells (DSSCs) using CrS thin film Jsc (22.5 mA/cm2).

Optical Properties of Cadmium Sulphide (CdS) Thin Films Spin-Coated on Glass Substrates

Abstract: CdS thin films were synthesized on a glass substrate using spin coating method. The effects of annealing temperature on the optical properties of the prepared CdS films were investigated for different annealing temperatures of 200, 300 and 400 °C. Cadmium acetate, thiourea and ammonia were used as the source materials for the preparation of the thin films. The elemental composition, morphological, optical and structural properties of the films obtained by spin coating were investigated using Energy Dispersive X- ray Spectroscopy (EDAX), Scanning Electron Microscope (SEM), UV Spectrophotometry and X-ray diffraction (XRD) respectively. The SEM image of the unannealed film shows a spherical morphology and an irregular pattern without any void. It also shows that the film covers the substrate well. Annealing leads to an increase in transmittance with the highest transmission of 87% observed for the film annealed at 400oC. With increase in annealing temperature, optical parameters like extinction coefficient and dielectric constants show a reduction, while refractive index and skin depth exhibit an improvement. The absorption coefficient increases with increasing photon energy in the range 3.6 to 4.0 eV. The band gap values of the CdS thin film samples were found to be in the range between 3.14 eV and 3.63 eV. The bandgap is somewhat greater than the value of bulk CdS due to quantum size effect. EDX image confirmed the presence of Cadmium and Sulphur in the prepared CdS films. Annealing did not significantly change the extinction coefficient. The X-ray diffraction confirms the cubic structure of CdS deposited on glass substrate, where reflections from (111), (200), (220) and (311) planes are clearly shown with a preferential orientation along (111) plane. Debye-Scherer equation was used to determine the crystallite size of the most intense plane (111) and the value was found to be 8.4 nm. Keywords: SEM image, Spin coating, Surface morphology, Optical properties, Annealing.

Fabrication, Structural, Optical, Electrical Properties and Influence of Complexing Agents on Ternary CuZnS2 Thin Film

In the present work, copper zinc sulphide (CuZnS2) thin films with and without complexing agents using glass plate as substrate were prepared. Chemical bath deposition method was employed to deposit the thin films. Powder X-ray diffraction (PXRD) patterns of the prepared films indicate the crystalline nature of CuZnS2 with cubic phases. The SEM and AFM images illustrate that the deposited films were highly influenced on the polyhedral morphology by the complexing agents. The influence of complexing agents on absorbance and band gap of the CuZnS2 thin films were characterized using UV-Vis absorption studies. Hall effect measurements indicate the CuZnS2 thin film without surfactant belongs to p-type semiconductor and become n-type after adding the complexing agents EDTA and Leishman stain. From the I-V curve, all the samples having slow conducting nature was found for changing the voltage with the current from -32 nA to +30 nA using solar stimulator.

Effect of molar concentration on the physical properties of NiS thin film prepared by spray pyrolysis method for supercapacitors

The present study reports on the deposition of Nickel sulfide (NiS) thin films on glass substrates by spray-pyrolysis at 300 ± 5 °C with different concentrations of nickel precursor (0.03, 0.05, and 0.07 M). The precursor aqueous solutions were synthesized using hexahydrated nickel nitrates and thiourea with a stabilization ratio nickel/sulfur of 1/3. The X-ray diffraction (XRD) study revealed a polycrystalline character with a hexagonal crystal structure. The crystallites size varied from 23.9 to 42.7 nm with an increase in the precursor’s concentration. Furthermore, the optical band gap decreases from 1.07 to 0.96 eV. The elementary composition analysis confirmed the presence of Ni and S elements in the samples. Both scanning electron microscopy (SEM) and atomic force microscopy (AFM), revealed a homogenous crack-free and compact appearance in all scanned areas with spherical grains. In addition, the roughness of the films significantly increases with the increase of the precursor’s concentration. On the other hand, the film prepared with 0.05 M exhibits a high electrical conductivity and capacitance ca. 1.97 × 103 S/cm and 115 µF/cm2, respectively, at room temperature. The above results showed that the films prepared in this study are very attractive as an electrode material for application in supercapacitors.

Study of Selected Morphologic, Structural and Optical Effects of Silver Coated CBD-CdS Thin Films

This work focused on comparing cadmium sulphide (CdS) thin films with and without CdS silver aggregates (CdS:Ag) deposited on the surface. We report absorption and transmission responses. Using the Tauc method, we obtained direct band gap energies with values of 2.50 (CdS) and 2.49 eV (CdS:Ag). We performed a scanning electron microscope characterization at different magnifications were cluster formations with granular shapes were observed. The highest magnification of 50,000× showed silver clusters as shiny granulates, which were confirmed by microprobe elemental mapping at a magnification of 18,000×. Energy Dispersive Spectroscopy revealed that the light composition of the silver clusters was the unique difference from the CdS thin film. X-Ray Diffraction results only detected the hexagonal CdS pattern, but not that of silver. The crystallite size was of around 13 nm. A Surface-Enhanced Ramman Scattering effect was observed upon the silver coating of the CdS thin film at 293.3 cm–1.

Effects of Thickness on Optical and Structural Properties of Lead Sulphide (PbS) Thin Film Prepared by Chemical Bath Deposition (CBD)

Nanocrystalline PbS thin films were deposited on glass substrates with various deposition times using chemical bath deposition technique. PbS thin films were prepared by using a solution of Lead nitrate and thiourea by using NaOH salt as a complexing agent and ammonia solution as a pH adjuster at 65 0 C. The study was carried out for thickness in the range of (0.16-1.03m). The structural properties were carried out by X-ray diffraction (XRD). The X-ray diffraction patterns reveal that the films exhibit the cubic face centered structure. The crystalline sizes of the films increased with increasing film thickness. The morphological properties were studied by SEM and showed that films were well adherent to the substrate, uniform, small crystal size and covered the entire substrate surface completely. The optical properties of these films have been studied and show that PbS thin films have the values of energy gap varied between (0.88-1.34 eV) with increasing film thickness. Keywords: CBD, XRD, band gap, PbS thin film DOI: 10.7176/CMR/12-7-01 Publication date: September 30 th 2020

Simultaneous etching of underlying metal oxide and sulfide thin films during Cu2S atomic layer deposition

Herein, we report the simultaneous etching of selected metal oxide and sulfide underlayers during the atomic layer deposition (ALD) of Cu2S. The unexpected etch was observed to be prompted by the infiltration of highly mobile Cu+ ions from a top ALD Cu2S layer into underlying films, followed by fragmentation of the underlayers and subsequent outward diffusion of both cations and anions from the underlayers to the Cu2S surface. A strong correlation was observed between the susceptibility to etching, etch rates and the bond dissociation energies of the underlayers. ZnS, ZnO, SnS, and SnO thin films were etched at different rates, while SnO2 exhibited high resistance to etching. Interestingly, the etch process exhibited self-limiting characteristics dependent on the Cu precursor and H2S gas dose times, thus indicating simultaneous Cu2S ALD and controlled sublayer etching reactions. Based on the findings, we proposed a possible mechanism by which the etching proceeds. We further explored, the synthesis of 3-dimensional Cu2S/ZnO and Cu2S nanowires using ALD Cu2S and the observed ZnO etching phenomenon.

Nano Structural Properties of Lead Doped Cadmium Sulfide (Cd1-xPbxS) Thin Films Deposited by Spray Pyrolysis Technique

Nano Structural Properties of Lead Doped Cadmium Sulfide (Cd1-xPbxS) Thin Films Deposited by Spray Pyrolysis Technique

Tunability and Graded Energy Band Gap of Chemical Bath Deposited Cadmium Sulfide (CdS) Thin Film for Optoelectronic Applications

CdS thin films have continued to receive scientific and technological attention due to their potential applications in efficient solar energy conversion and utilization in device fabrication. In this research, CdS thin films were deposited on indium doped tin oxide (ITO) substrates of dimension 2.3 by 2.4 cm2. Three different aqueous bath solutions of CdS were formed by increasing the concentration of cadmium acetate as a source of cadmium while the concentration of ammonium chloride and thiourea as a source of sulfur remained constant in the reaction bath as against the usual convention to ascertain the strength of the constituents in the reaction. The energy band gap of the films decreases with increase in the concentration of cadmium as a constituent of the bath while the films optical transmittance was found to increase with increase in concentration. This indicates that the energy band gap of the films can be predetermined by the choice of the constituent of the concentration in the chemical bath deposition technique (CBD). The increase in the transmittance for both as deposited and annealed CdS confirms the suitability of the films as window layer device, solar cell and optoelectronic applications.

Influence of Bath Temperature on Structural, Optical and Electrical Properties of Cadmium Sulfi de Thin Films Prepared by Chemical Bath Deposition

Abstract. The effect of bath temperature (60-90 °C) on structural, optical and electrical propertiesof CdS thin films deposited by chemical bath deposition (CBD) at a constant precursorconcentration and deposition time was studied. From the XRD analysis, it was found that thestructure of CdS thin fi lms varied with temperature. At lower temperature hexagonal structurewas dominated while at high temperature, the cubic structure was prominent. The band gap ofthe as-prepared CdS thin fi lms was calculated from the UV-Vis spectroscopic data, and it wasfound to be decreased with the increase of temperature. The resistivity of the CdS thin fi lms alsodecreased with the increase in temperature.
 
 
 
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Structural, electrical and optical properties of CdS thin films and the effect of annealing on photoconductivity

Cadmium sulfide (CdS) thin films with n-type semiconductor characteristics were prepared by flash evaporating method on glass substrates. Some films were annealed at 250 oC for 1hr in air. The thicknesses of the films was estimated to be 0.5µ by the spectrometer measurement. Structural, morphological, electrical, optical and photoconductivity properties of CdS films have been investigated by X-ray diffraction, AFM, the Hall effect, optical transmittance spectra and photoconductivity analysis, respectively. X-ray diffraction (XRD) pattern shows that CdS films are in the stable hexagonal crystalline structure. Using Debye Scherrerś formula, the average grain size for the samples was found to be 26 nm. The transmittance of the samples was determined from optical trasmittance spectra. It is observed that the direct band gap energy for as deposited and annealed films are (2.55, 2.45) eV, respectively. The effect of annealing at 250 oC for 1hr in air on optical and photoconductivity of films under various intensity of illuminations (43.81 and 115.12) mW/cm2 was studied. The dark and photocurrents of the annealed films were found to be greater than that of as deposited.

Morphological Changes of SnS Thin Films Deposited on Stainless-Steel Substrates at Low Temperatures

Orthorhombic tin sulfide (SnS) thin films have been deposited on stainless steel (SS) substrates by Chemical Bath Deposition (CBD) at 25, 35 and 70 °C with a deposit time of 8 hours each one. XRD analysis showed that samples obtained at 25 °C and 70 °C present very small diffraction peaks. This can be attributed in the case of the sample obtained at 25 degrees, that the crystallization process is not completed because the temperature is so low and in case of the sample deposited at 75 degrees, a redissolution of the material is carried out. However, sample obtained at 35 °C was polycrystalline with orthorhombic structure and preference plane (111). All samples showed the Raman vibrational modes TO and LO of the SnS and confirms that the samples do not have by-products. It was observed from SEM micrographs that the films consisted of spheres for the sample deposited at 25 °Candsmall flakes for the other samples. From diffuse reflectance measurements the optical band gap calculated was between 1.45 eV to 1.59 eV.

Electric Double Layer Field Effect Transistor Using SnS Thin Film as Semiconductor Channel Layer and Honey Gate Dieletric

The study aimed at the investigation and application of SnS thin film semiconductor as a channel layer semiconductor in the assembly of an electric double layer field effect transistor which is important for the achievement and development of novel device concepts, applications and tuning of physical properties of materials since the reported EDLFET and the modulation of electronic states have so far been realised on oxides, nitrides, carbon nanotubes and organic semiconductor but has been rarely reported for the chalcogenides. Honey was used as a gel like electrolytic gate dielectric to generate an enhanced electric field response over SnS semiconductor channel layer and due to its ability to produces high on-current and low voltage operation while forming an ionic gel-like solution similar to ionic gels which consist of ionic liguids. SnS gated honey Electric double layer field effect transistor was assembled using tin sulphide (SnS) thin film as semiconductor channel layer and honey as gate dielectric. The measured gate capacitance of honey using LCR meter was measured as 2.15 μF/ cm2 while the dielectric constant is 20.50. The semiconductor layer was deposited using Aerosol assisted chemical vapour deposition and annealed in open air at 250 on an etched region about the middle of a 4×4 mm FTO glass substrate with the source and drain electrode region defined by the etching and masking at the two ends of the substrate. Iridium was used as the gate electrode while a copper wire was masked to the source and drain region to create electrode contact. The Profilometry, X-ray diffraction, Scanning electron microscope, Energy dispersive X-ray spectroscopy, Hall Effect measurement and digital multimeters were used to characterise the device. The SnS thin film was found to be polycrystalline consisting of Sn and S elements with define grains, an optical band of 1.42 eV and of 0.4 μm thickness. The transistor operated with a p type channel conductivity in a depletion mode with a field effect mobility of 16.67 cm2/Vs, cut-off voltage of 1.6 V, Drain saturation current of1.35μA, a transconductance of -809.61 nA/V and a sub threshold slope of -1.6 Vdec-1 which is comparable to standard specifications in Electronics Data sheets. Positive gate bias results in a shift in the cut off voltage due to charge trapping in the channel/dielectric interface.

Copper Incorporation into CdS Thin Films by Ionic Exchange in an Aqueous Solution Process at Room Temperature

Cadmium sulfide (CdS) thin films were deposited, on glass substrates, at 70°C for 120 min using an ammonium-free chemical bath deposition process. After deposition, the films were placed in a CuCl2 solution for 45, 60, 75, and 90 min, respectively, for their ion exchange, generating CdxCu1-xS films. The obtained films were analyzed by X-ray diffraction, Raman spectroscopy, X-ray wavelength dispersion spectrometry, and scanning electron microscopy. The reference CdS films showed a homogeneous appearance and a yellowish color; elapsing the immersion time, the films changed their color showing a greenish appearance. The X-ray analysis indicated that the CdS films developed a hexagonal structure with preferential orientation along the plane (002). During the ion exchange, a decrease in the intensity of the reflection (002) was observed as well as a slight displacement of this reflection towards higher values of 2θ derived from the substitution of Cd atoms by Cu atoms. The WDS analysis revealed that approximately 10% of the cadmium atoms were replaced by copper ones after 90 min of immersion.

Synthesis and Electrical, Optical, Electrochemical Properties of Chemically Deposited PbS Thin Films

Lead Sulphide (PbS) thin film was deposit by chemical bath deposition (CBD) process on the glass substrate at room temperature for various time intervals. The precursors used for this deposition are lead acetate since as a supply of lead ions (Pb2+) and thiourea the same as the supply of sulfide ions (S2-) with 0.1M concentration. The pH of the mixed precursors solution was maintained at 9.5-10 by addition of drop by drop ammonia very slowly. The cause of deposition time for different hours studied. The influence of deposition time on properties of PbS film was investigated. The color of films appears black-gray after taking out of the bath. The thickness of the film is increased with increase in deposition time. The electrical resistance and resistivity were 500MΩ and 18.75 MΩ-cm and band gap measured as a function of temperature using D.C. four probe methods was 0.3742 eV. The Cyclic Voltammetry (CV), Linear Sweep Voltammetry (LSV), Chronoamperometry were studied by using potentiostat.