Cadmium Indium Selenide Research Articles

Ozone and NaCl Based Electrolytic Solar Cell; It’s Working Principle, Advantages and Possibilities

Proposed idea on novel solar cell i.e. ozone and NaCl based electrolytic solar cell and its design is presented in present paper. The working mechanism of proposed solar cell is different from the latest solar cells based on silicon (Si), gallium-arsenide (GaAs), cadmium-telluride (CdTe), cadmium-indium-selenide (CIS) and cadmium-indium-gallium-selenide (CIGS), dye sensitized and polymer solar cell. The maximum theoretical output power for 100% dissociation of ozone gas molecules by visible light and also due to adsorption of Na+1 ions on the cathode and O−2 ions adsorbed on the anode resulting in galvanic effect would be 2.68 × 1017 W/(h-sq km) in 1 month. The feasibility with respect to cost of the ozone and NaCl based electrolytic solar cell was checked by comparing it roughly with the latest solar cells based on silicon and other solar cells and conventional methods of producing electricity (i.e. hydro and thermal). The total cost (initial investment) required to produce the power output of 12 × 1013 W.h in 1 month to meet the entire power need of India by establishing solar power plant with latest and existing solar cell technology would be 4.2 × 1016 INDIAN rupees. The total initial investment required to produce the power output of 12 × 1013 W.h in 1 month to meet the entire power need of India by conventional method (hydro and thermal) is 12 × 1010 INDIAN rupees. In the case of ozone and NaCl based electrolytic solar cell, the total initial investment required to produce the power output of 12 × 1013 W.h in 1 month to meet the entire power need of India would be 5.32 × 1011 INDIAN rupees. This indicates that the initial investment required for the ozone and NaCl based electrolytic solar cell would be five orders of magnitude (105 times) less than the requirement for the latest and existing solar cells as mentioned above and would be around same as that of conventional method (hydro, thermal) to produce the power output of 12 × 1013 W.h in 1 month to meet the entire power requirement of India. The advantages of the ozone and NaCl based electrolytic solar cells is presented in this paper. Moreover, it is also found that the area required to set up solar power plant once the technology for ozone and NaCl based electrolytic solar cell is developed would be 1.08 × 1010 sq. feet and this would cost around 2.4 × 1012 INDIAN rupees at the rate of 2 × 105 INDIAN rupees per 100 sq. yard to produce power output 12 × 1013 W.h in 1 month to meet the entire power requirement of India. The area required for setting up solar power plant to produce 12 × 1013 W.h with Si based or other latest solar cell would be 3 × 1010 Sq. Feet and this would cost around 6.7 × 1012 INDIAN rupees at the rate of 2 × 105 INDIAN rupees per 100 sq. yard. This indicates that around one third the area is required to set up power plant with ozone and NaCl based electrolytic solar cell and this would reduce the cost of land when compared to Si or other latest solar cells.

(Photo)electrochemical analysis of electrosynthesized fibrous cadmium indium selenide (CdIn2Se4) thin films

Abstract Electrosynthesized cadmium indium selenide (CdIn 2 Se 4 ) thin films were (photo) electrochemically analyzed by current–voltage characteristics, photoresponse, speed response, electrochemical impedance study, and capacitance–voltage characteristics. The improved photoconversion efficiency of electrosynthesized CdIn 2 Se 4 thin film-based photoelectrochemical cell explained with the help of theoretical modeling of energy band diagram and equivalent circuit model of the impedance spectra of the photoelectrochemical cell.

Cadmium indium selenide semiconducting nanofibers by single step electrochemical route

The growth of ternary semiconductor thin films of cadmium indium selenide nanofibers has been carried out from aqueous solution of cadmium sulphate, indium trichloride, and selenium dioxide by electrochemical route. These thin films have been further optimized using photoelectrochemical cell (PEC). Optimized thin film has been characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Photoelectric Properties of Pulse Electrodeposited CdIn2Se4 Films

Among II–III–VI group ternary compounds, Cadmium indium selenide (CdIn2Se4) is one of the interesting semiconductors due to its optical absorption property, band gap and low electrical resistance. CdIn2Se4 is a direct band gap semiconductor with an energy gap of 1.73 eV which make them interesting for solar cells through photoelectrochemical route. The material in thin film form can be obtained by electrodeposition, vacuum evaporation and spray pyrolysis. In this work, the pulse electrodeposition technique was used for the deposition of CdIn2Se4 films for the first time.CdIn2Se4 films were pulse electrodeposited at different duty cycles in the range of 6 – 50 %. The deposition potential was maintained at – 0.95 V(SCE). Titanium and conducting glass substrates were used as substrates. The films were deposited at 80°C. The precursors used were 0.1 M CdSO4, 0.25 M In2(SO4)2 and 5 mM SeO2 in diethylene glycol. Thickness of the films measured by Mitutoyo surface profilometer increased from 600 – 950 nm with increase of duty cycle.X-ray diffraction pattern recorded for CdIn2Se4 thin films prepared on titanium substrates revealed that the deposited films are polycrystalline with tetragonal structure with lattice constants (a = 5.77 Å; c = 11.59 Å). The diffraction peaks of tetragonal CdIn2Se4 with the lattice planes (101), (111), (112), (300), (311) and (104). All the peaks identified are from CdIn2Se4 and no additional lines corresponding to Cd, In and Se are present. The height of (111) peak increases with duty cycle, which indicates that the deposited films exhibits preferential orientation along (111) planes. It is also observed that the height of preferential peak is increased with duty cycle. The crystallite size of the deposited films are calculated using FWHM data and Debye Scherrer formula variedc from 15 – 40 nm.Composition of the films was studied by EDS analysis of Cd1.01In1.96Se4.03 for the films deposited at 50 % duty cycle which indicates the nearly stoichiometric composition.The band gap energy of CdIn2Se4 varied in the range of 1.97 eV – 2.16 eV as the duty cycle decreased. This variation is due to quantum size effects. The grain size of the films deposited at lower duty cycle is lower compared to the films deposited at higher duty cycles.The variation of photocurrent with light intensity of CdIn2Se4 films deposited at different duty cycles exhibited linear behaviour. The increase in photocurrent is attributed to an increase in the majority carrier concentration and/or an increase in impurity centers acting as traps for minority carriers. The variation of photocurrent with applied voltage in CdIn2Se4 films is also linear. Photosensitivity is the ratio of the increase in conductivity of the material in the presence of light to the conductivity in darkness It seems that some transitions that create additional free carriers effectively increase the free life time increasing the photosensitivity of the material. A plot of photosensitivity versus light intensity of CdIn2Se4 thin films is also linear. Thinner films exhibit moderate photosensitivity, whereas thicker films are found to exhibit higher photosensitivity. Crystallographical imperfections acting as trapping centers will enhance the photosensitivity, whereas the recombination centers decrease the photosensitivity.Single phase CdIn2Se4 films could be prepared by the pulse electrodeposition technique. Films with grain size in the range of 15 nm – 40 nm cane be prepared. Films with band gap in the range of 1.97 eV – 2.16 eV can be obtained.Photosensor studies indicated linear photocurrent – voltage and linear photocurrent – illumination characteristics showing that these films can be used in optoelectronic applications.

Photoelectrochemical performance of sprayed n-CdIn 2Se 4 photoanodes

Cadmium indium selenide thin films have been synthesized by spraying mixture of equimolar solution concentrations of cadmium chloride, indium trichloride and selenourea in aqueous media onto preheated FTO coated glass substrates at optimized substrate temperature and solution concentration. The photoelectrochemical cell configuration of n-CdIn 2Se 4/(1 M NaOH + 1 M Na 2S + 1 M S)/C has been used for investigate the current–voltage characteristics under dark and white light illumination, photovoltaic output, spectral response, photovoltaic rise and decay characteristics. It reveals the film of CdIn 2Se 4 exhibits n-type conductivity. The junction quality factor in dark ( n d ) and light ( n l ), series and shunt resistance ( R s and R sh ), fill factor (FF) and efficiency ( η) for the cell have been estimated. Gartner’s model was used to calculate minority carrier diffusion length and donor concentration ( n D ). The observed efficiency and FF of PEC solar cell is 1.95% and 0.37% respectively. Mott–Schottky plot shows the flat-band potential ( V fb ) of CdIn 2Se 4 films is −0.655 V/SCE.

(Photo) electrochemical investigations on spray deposited n-CdIn 2Se4 thin film/polysulphide/c photoelectrochemical solar cell1

Cadmium indium selenide (n-CdIn 2Se4) thin films have been synthesized by spraying the mixture of an equimolar solutions of cadmium chloride [CdCl2], indium trichloride [InCl3] and selenourea [(NH2)2CSe] in aqueous media onto preheated fluorine doped tin oxide (FTO) coated glass substrates at optimized parameters of substrate temperature and solution concentration. The photoelectrochemical (PEC) cell configuration of n-CdIn2Se/(l MNaOH + 1 MNa2S + 1 M S)/C has been used for investigating the current—voltage (I–V) characteristics under dark and white light illumination, photovoltaic output, spectral response, photovoltaic rise and decay characteristics. The PEC study reveals the thin film of CdIn2Se4 exhibits n-type conductivity. The junction quality factor in dark (nd) and light (nl), series and shunt resistance (Rs and Rsh), fill factor (FF) and efficiency (η) for the cell have been estimated. The observed efficiency and FF of PEC solar cell is found to be 1.95 and 0.37% respectively. Mott-Schottky plot shows the flat-band potential (V fb) of n-CdIn2Se4/(l M NaOH + 1 M Na2S + 1 M S)/C cell to be—0.655 V/SCE.

Electrosynthesis and studies on Cadmium-Indium-Selenide thin films

Thin films of Cadmium Indium Selenide (CdIn2Se4) have been deposited on indium doped tin oxide coated conducting glass (ITO) substrates using potentiostatic cathodic electrodeposition technique. Cyclic voltammetry has been carried out in order to fix the deposition potential in the range between −1500 and +600 mV versus SCE. X-ray diffraction pattern shows that the deposited films exhibit tetragonal struc- ture with most prominent reflection along (200) plane. The dependency of microstructural parameters such as crystallite size, strain and dislocation density with deposition potential has been studied. Surface morphology and film composition have been analyzed using scanning electron microscopy and energy dispersive analysis by X-rays, respectively. EDX analysis reveals that films with well defined stoichiom- etry has been obtained at a deposition potential −950 mV versus SCE. The optical band gap, refractive index and extinction coefficient are evaluated from optical absorption measurements. The experimental observations are discussed in detail.

PREPARATION OF CdIn2Se4n-TYPE SEMICONDUCTOR USED AS THERMOELECTRIC MATERIAL BY SOL–GEL METHOD

The objective of this research was to study the effect of various parameters such as temperature and pH to the formation of cadmium indium selenide ( CdIn2 Se 4 ) thin films, which were fabricated by sol–gel dip-coating method. This n-type semiconductor compound is suitable for application as thermoelectric materials. Cadmium, indium, selenium precursors were separately dissolved by solvents: ethanol, hydrochloric acid, and acetic acid to form metal alkoxides. The precursor solutions were then mixed together in N 2 atmosphere. These metal alkoxides were hydrolyzed by adding water and then polycondensed by adding ethylene glycol to become gels. These gels were adjusted to various acid-base values by adding diethylnolamine. Glass substrates were dipped into the gels to form thin films. These thin films were annealed at various temperatures in N 2 atmosphere and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and fourier transfrom infrared spectroscopy (FTIR) techniques. The results indicated that CdIn2 Se 4 compound occurred by the reaction at room temperature with pH 4 and annealed at 450°C in N 2 atmosphere.

Electrochemically deposited photoactive CdIn 2Se 4 thin films: Structural and optical studies

Electrochemical synthesis of photoactive cadmium–indium–selenide (CdIn 2Se 4) thin films at ambient temperature was reported. The nanocrystalline nature and 1:2:4 elemental chemical stoichiometric ratio for Cd, In and Se were obtained from the X-ray diffraction and energy dispersive X-ray analysis, respectively. Irregular shaped islands of about 400–500 nm in sizes composed of large number of small (∼30–40 nm) spherical grains were confirmed from the atomic force microscopy and the scanning electron microscopy images. The photoelectrochemical measurement of CdIn 2Se 4 film electrode in presence of 1 M polysulphide electrolyte revealed 0.42% photoelectrochemical device conversion efficiency, under the light illumination intensity of 80 mW/cm 2.

Properties of spray-deposited CdIn2Se4 thin films for photovoltaic applications

Thin films of cadmium indium selenide have been deposited onto amorphous glass substrates using a simple and low-cost spray pyrolysis technique. The aqueous solutions containing precursors of Cd, In and Se have been used to obtain good quality deposits at optimized substrate temperature. The preparative parameters such as concentration, substrate temperature, etc. have been optimized by photoelectrochemical technique. The films have been characterized by techniques such as X-ray diffraction, scanning electron microscope, EDAX and electrical characterization. The photoelectrochemical characterization shows that both short-circuit current (I sc ) and open-circuit voltage (V oc ) are at their optimum values at the optimized substrate temperature of 280C and concentration (0.0125 M). The XRD patterns show that the films are polycrystalline with cubic structure. The SEM studies reveal the compact morphology with large number of grains. Compositional analysis reveals that the material formed is nearly stoichiometric at the optimized preparative parameters. The electrical resistivity shows that the films are semiconducting and the resistivity is found to be minimum at optimized substrate temperature. The thermoelectric power (TEP) measurement reveals that the TEP is relatively maximum at same substrate temperature of 80°C. Photovoltaic output characteristics study reveals that the fill factor and efficiency; to be 69% and 3%, respectively.

Structural and optical properties of spray-deposited CdIn2Se4 thin films

The thin films of cadmium indium selenide (CdIn2Se4) have been deposited onto amorphous glass substrates using simple and low cost spray pyrolysis technique. The aqueous solutions containing precursors of Cd, In and Se have been used to obtain good quality deposits at different substrate temperatures. The preparative parameters, such as substrate temperature and concentration of precursor solution have been optimized and are found to be 280°C and 0.0125M, respectively. The films have been characterized by X-ray diffraction (XRD), optical absorption and energy dispersive analysis by X-rays (EDAX) techniques. The spray-deposited CdIn2Se4 films are polycrystalline with cubic crystal structure. The optical absorption studies reveal that the transition is direct with band gap energy Eg=1.92eV. The EDAX studies reveal that the films obtained at substrate temperature 280°C are nearly stoichiometric.

Radiative recombination in CdIn2Se4: Photoluminescence spectra

l I III IV The photoluminescence of many ternary semiconductors of the A B 2 X 4 family has been studied by different authors in the last two decades (~); some interesting properties have been put in evidence, but a systematic analysis and a comparison of the results together with an interpretation of the recombination process in ternary semiconductors are still lacking. More recent works on three compounds of the family (ZnIn2S 4 (~), ZnIn~Se 4 (3) and and CdIn2S 4 (a)) seem to suggest that a unique mechanism can explain the recombinat ion process. In the light of a systematic study of all the compounds of the family, this letter deals with the luminescence of the relatively unknown cadmium indium selenide (CdIn2S%). Cadmium indium selenide is a n-type semiconductor with defect chalcopyrite structure (5); its main transport properties have been measured by KOVAL et al. (6), while BALDBR~SCHI and coworkers have calculated the energy band structure of this semiconductor; in particular, they have shown that some energy levels are very sensltive to the position of the atoms in the cell, i .e . to the internal distortion (7). The optical and photoelectrical properties have been studied in detail by TRYKOZKO (s), who has shown that the indirect and the direct gaps of CdIn~S% at liquid-nitrogen temperature are located at 1.60 eV and 1.84 eV, respectively. To the best of our knowledge there is only one published paper on the photoluminescenee of CdIn2Se a,