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Effect of Additives on Optical Measurements of NiSe2 Thin Films
Available online at www.sciencedirect.com
Procedia Engineering 53 (2013) 555 – 561
Malaysian Technical Universities Conference on Engineering & Technology 2012, MUCET 2012 Part 2 Mechanical And Manufacturing Engineering
Effect of Additives on Optical Measurements of NiSe2 Thin Films T. Joseph Sahaya Anand ª,* Mohd. Zaidana and S. Shariza a a
Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka, 76109 Melaka, Malaysia
Abstract Nickel selenide, NiSe2 is one of the absorbent materials used in thin film technology in photoelectrochemical (PEC) cell. Electrodeposition is a preferred method to produce NiSe2 thin films due to its advantages such as the possibility of large scale production, minimum waste of components, easy monitoring of deposition process and large area deposition.Ethylenediaminetetraacetic acid (EDTA) and triethanolamine (TEA) were employed as the additives during the deposition. The samples were deposited within 30 minutes deposition time according to potential acquired from cyclic voltammetry measurements. Thin film thickness measurements, structural studies, optical studies, morphological and compositional analysis as well as Mott-Schottky measurements were carried out. . © Published by Elsevier Ltd. Ltd. © 2013 2013The TheAuthors. Authors. Published by Elsevier Selection peer-review under responsibility of the Research & Innovation Centre, UniversitiCentre, Malaysia Selectionand and/or peer-review under responsibility of theManagement Research Management & Innovation Universiti Malaysia Perlis Perlis. Keywords:thin film; photoelectrochemical; nickel selenide; electrodeposition; additive.
1. Introduction Transition metal nickel chalcogenides NiX2 (X Se, S and Te) have been showing the great potential as new thin film materials for solar energy conversion in the efforts to replace the conversional material. Due to its significant characteristics by optical and semiconducting properties, transition metal chalcogenide compounds, especially in thin film form were discovered to be the right material in the photovoltaic industry for the development of photoelectrochemical (PEC) and solar cell panels [1]. The rationale for this is that thin-film solar panels are expected to be economical to be manufactured due to their reduced costs of material, energy, handling as well as capital. The minimization of the amount of material used, the use of cost effective materials, processing methods and mounting arrays contribute to the achievement of reduction cost of thin film cells.Liquid phase chemical techniques include electrodeposition, chemical bath deposition, iodization and spray pyrolysis. Electrodeposition had been employed to fabricate NiSe2 thin films [1-2].
* Corresponding author. E-mail address: [email protected]
1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the Research Management & Innovation Centre, Universiti Malaysia Perlis doi:10.1016/j.proeng.2013.02.071
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T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
2. Exprimental Procedures 2.1. Preparation of ITO Coated Glass Substrate and Experimental Setup Ultrasonic cleaner was used to clean up the substrates immersed in ethanol and distilled water, 10 minutes respectively [3]. Then they were dried in mechanical convection oven for 5 minutes.The nickel selenide thin films were prepared from aqueous solutions of nickel sulphate, NiSO4 and sodium selenite, Na2SeO3 acted as a source of Ni2+ and Se2-ions respectively. There were three kinds of electrolyte solutions prepared as specified below. (a) 1.12g NiSO4 powder + 120mL deionised water + 3.12g Na2SeO3 powder + NaOH (b) 1.12g NiSO4 powder + 120mL deionised water + 4g EDTA + 3.12g Na2SeO3 powder + NaOH (c) 1.12g NiSO4 powder + 120mL deionised water + 12mL TEA + 3.12g Na 2SeO3 powder + NaOH Sodium hydroxide was added to acquire the alkaline condition to help the formation of Se2- from Na2SeO3[4]. 2.2. Cyclic Voltammetry (CV), Electrodeposition Experiments and Characterisations Using Princeton Applied Research Model VersaSTAT 3 Potentiostat,cyclic voltammetry (CV) between to common potential limits (-2.00 to 2.00 V) was run to determine the potentials for electrodeposition [5]. The deposition of films was in 30 minutes [2].Figure 1below shows a three electrode cell system adopted for the cyclic voltammetry analysis and deposition of the film.
Fig. 1. The experimental set-up of both cyclic voltammetry and electrodeposition.
Thin film thickness was measured using gravimetric weight difference method. X-ray diffractograms of the thin film was obtained from a PAN analytical XPERT PROMPD PW 3040/60 diffractometer using monochromatic Cu K radiation [6].The morphological analysis of NiSe2 thin film was studied by using optical microscope and JSM-6400 JEOL Scanning Electron Microscope, SEM while compositional study of NiSe2 thin film was conducted using Energy Dispersive X-ray Spectroscopy (EDX). Optical absorption had been studied using Shimadzu 1700 UV-Vis Spectrophotometer in the wavelength region of 200-1100 nm. Zentech A3302-01 Test Leads LCR Meter was used to draw the Mott-Schottky plot. 3. Results and Discussion Fig. 2, 3 and 4 show the cyclic voltammogram of NiSe2in three different environments.
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557
Fig. 2. Cyclic Voltammogram of NiSe2 in the absence of additive.
Fig. 3. Cyclic Voltammogram of NiSe2 in the presence of EDTA.
Fig. 4. Cyclic Voltammogram of NiSe2 in the presence of TEA.
Deposition potentials of -1.2, -1.1 and -0.6 V were obtained from Figures 2, 3 and 4 respectively. The current drop indicates the oxidation of nickel compound [7]. The values of thin film thickness at all electrolyte conditions are comparable where the addition of additive in the electrolyte did not give the prominent influence on the thin film thickness as shown in Table 1.
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T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561 Table 1. Thin Film Thickness In Different Electrolyte Condition Sample
Area (cm2)
Mass (×10-3) g
Thin film thickness (×10 -7) m
NiSe2
1.30
0.8
9.158
NiSe2 + EDTA
1.31
0.8
9.088
NiSe2 + TEA
1.29
0.9
10.382
Structural studies were performed at grazing angle incidence (the incidence angle was set at 1.5°) in order to reduce the intensity of the radiation reflected by the substrate [8]. Figure 5 shows the best peaks obtained among the three electrolyte conditions with the formation of desired NiSe2 peaks. The sharp peaks of XRD pattern obtained reveal that the NiSe2 thin films are polycrystalline in nature. (011), (101) and (031) planes that present in the presence of TEA indicate the NiSe2 thin films. The structural features fit into orthorhombic structure of NiSe2 films with lattice parameter values a =0.4890, b = 0.5960 and c = 0.36700 nm which comply with the standard values. Most of the peaks of ITO substrate are only obvious at 30 minutes deposition time. Another film, Ni3Se4 was observed at(002) and (110) planes. NiSe2 thin film deposited in the presence of TEA at 30 minutes deposition timewas chosen to study the surface morphologyand composition due to its best adhesion and well-distribution onto the substrates. The uniformity on the surface area of the film was exposed in 500 times magnifications as shown in Fig. 6 below.
Fig. 5. X-ray diffraction pattern of NiSe2 thin films (in the presence of TEA) deposited at different reposition times.
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Figure 6. SEM micrographs of NiSe2 obtained as experimental result (40 5 °C, pH 10) at 500 times magnification.
The SEM micrographs shows well-adherent, smooth, and uniform film surface without crack and pinhole [9], [10]. Figure 7 proves the presence of nickel and selenium together with other constituents (Si and O) in composional studies. The presence of silicon is due to the use of ITO coated glass substrates that contain this element while the presence of oxygen is expected from the surrounding atmosphere.
Fig. 7. The EDX analysis of NiSe2 with TEA at 30 minutes deposition time.
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Fig. 8.The plots of (
)2 with respect to photon energy, Eg for nickel selenide thin film in 30 minutes deposition time.
The optical absorption data were analysed from the following classical relation A(hv E g ) n / 2
(1)
hv
where A is a constant between 107 and 108 m-1 , Eg is the energy gap that occupies the area between the bottom of the conduction band and the top of the valence band at the same wave vector K and n is the constant equal to 1 for direct band gap and 4 for indirect gap [11]. The plots of ( )2 with respect to photon energy, Eg for nickel selenide thin film in 30 minutes deposition timeis shown in Figure 8.The band gap values obtained are comparable to the values obtained by the previous researchers which are 1.61 eV of NiSe2 film without additive [12], 2.0 eV of NiSe2 film with TEA [7] and 1.4 eV of NiSe2 with EDTA [6].
Fig. 9. Mott-Schottky plot of NiSe2 in 30 minutes deposition time.
The Mott-Schottky plot drawn in the Figure 9 shows the positive slopes, indicating that the deposited films fall in the ntype conductivity of NiSe2, are negatively charged and have more electrons rather than holes. The intercept of linear plot (1/Ccs2 = 0) was taken as the electrode potential of the semiconductor at whichbond bending is equal to zero [13]. 4. Conclusion Nickel selenide thin films had been successfully deposited onto the indium tin oxide (ITO) coated glass substrate in three different electrolytes by using the potentials obtained from cyclic voltammetry experiment. The use of both TEA and EDTA as the additives had prepared two different electrolytes apart from the one without complexing agent. Structural studies revealed that the films synthesised in the presence of either EDTA or TEA comply the exact stoichiometry of NiSe2. SEM revealed the surface morphology of NiSe2 indicating the formation of microcrystals with the white spots in the dark region.The presence of nickel and selenium had been confirmed via compositional studies.The optical absorption studies have proven that the band gap values obtained fell in the semiconductor region and complied with the values acquired by
T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
561
the previous researchers. From Mott-Schottky plot, the deposited films fell in the n-type semiconductor, were negatively charged as well as having more electrons rather than holes. Acknowledgement The work described in this paper was supported by Universiti Teknikal Malaysia Melaka (UTeM) and FRGS / KeTTHA sponsored research grant (Project No. FRGS/2011/FKP/TK 02/1 F00120). References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13]
Pathan, H.M. and Lokhande, C.D., 2004. Deposition of metal chalcogenide thin films by successive ionic layer adsorption and reaction (SILAR) method. Bulletin Material Science, 27 (2), pp.85-111. Shariza, S. and Anand, T.J.S, 2011. Effect of Deposition Time on The Structural and Optical Properties of Molybdenum Chalcogenides Thin Films. Chalcogenide Letters, 8 (9), pp.529-539. Anuar, K., Saravanan, N., Wee, T.T., Soon, M.H. and Darren, T., 2010. Chemical Bath Deposition of Nickel Sulphide (Ni 4S3) Thin Films. Leonardo Journal of Sciences, 16, pp.1-12. Zhongbin, Z., Qing, P., Jing, Z., Xun, W. and Yadong, L., 2006. Controlled Hydrothermal Synthesis and Structural Characterization of a Nickel Selenide Series. Wiley Inter Science, 12 (10), pp.211-217. Villamena, F.A., Horak, V. and Crist, R., 2003. Cyclic Voltammetry of Metal Complexes of Nitrones and Nitroxides. Inorganica Chimica Acta, 342, pp.125-130. Anuar, K., Zainal, Z., Saravanan, N. and Kartini, A.R., 2004. Cathodic Electrodeposition and Characterization of Ni 3Se2 thin films. ASTJD, 21 (1), pp.19-25. Zainal, Z., Saravanan, N. and Mien, H.L., 2005. Electrodeposition of Nickel Selenide Thin Films in The Presence of Triethanolamine as a Complexing Agent. Journal of Material Science: Materials in Electronics, 16, pp.111-117. Toma, O., Iftime, S., Besleaga, C., Mitran, T.L., Ghenescu, V., Porumb, O., Toderus, A., Radu, M., Ion, L. and Antohe, S., 2011. New Investigations on Cadmium Sulfide Thin Films for Photovoltaic Applications. Chalcogenide Letters, 8 (12), pp.747-756. Delphine, S.M., Jayachandran, M. and Sanjeeviraja, C., 2005. Pulsed Electrodeposition and Characterization of Molybdenum Diselenide Thin Film. Material Research Bulletin, 40, pp.135-147. Roy, P. and Srivastava, S.K., 2006. Chemical Bath Deposition of MoS2 Thin Film Using Ammonium Tetrathiomolybdate as A Single Source for Molybdenum and Sulphur. The Solid Films, 496, pp.293-298. Ilican, S., Caglar, Y. and Caglar, M., 2008. Preparation and Characterization of ZnO Thin Films Deposited by Sol-gel Spin Coating Method. Journal of Optoelectronics and Advanced Materials, 10 (10), pp.2578-2583. Hankare, P.P., Jadhav, B.V., Garadkar, K.M., Chate, P.A., Mulla, I.S. and Delekar, S.D., 2010. Synthesis and Characterization of nickel selenide thin films deposited by chemical method. Journal of Alloys and Compounds, 490, pp.228-231. Anand, T.J.S., 2009. Synthesis and Characterization of MoS2 Films for Photoelectrochemical Cells. Sains Malaysiana, 38 (1), pp.85-89.
Procedia Engineering 53 (2013) 555 – 561
Malaysian Technical Universities Conference on Engineering & Technology 2012, MUCET 2012 Part 2 Mechanical And Manufacturing Engineering
Effect of Additives on Optical Measurements of NiSe2 Thin Films T. Joseph Sahaya Anand ª,* Mohd. Zaidana and S. Shariza a a
Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka, 76109 Melaka, Malaysia
Abstract Nickel selenide, NiSe2 is one of the absorbent materials used in thin film technology in photoelectrochemical (PEC) cell. Electrodeposition is a preferred method to produce NiSe2 thin films due to its advantages such as the possibility of large scale production, minimum waste of components, easy monitoring of deposition process and large area deposition.Ethylenediaminetetraacetic acid (EDTA) and triethanolamine (TEA) were employed as the additives during the deposition. The samples were deposited within 30 minutes deposition time according to potential acquired from cyclic voltammetry measurements. Thin film thickness measurements, structural studies, optical studies, morphological and compositional analysis as well as Mott-Schottky measurements were carried out. . © Published by Elsevier Ltd. Ltd. © 2013 2013The TheAuthors. Authors. Published by Elsevier Selection peer-review under responsibility of the Research & Innovation Centre, UniversitiCentre, Malaysia Selectionand and/or peer-review under responsibility of theManagement Research Management & Innovation Universiti Malaysia Perlis Perlis. Keywords:thin film; photoelectrochemical; nickel selenide; electrodeposition; additive.
1. Introduction Transition metal nickel chalcogenides NiX2 (X Se, S and Te) have been showing the great potential as new thin film materials for solar energy conversion in the efforts to replace the conversional material. Due to its significant characteristics by optical and semiconducting properties, transition metal chalcogenide compounds, especially in thin film form were discovered to be the right material in the photovoltaic industry for the development of photoelectrochemical (PEC) and solar cell panels [1]. The rationale for this is that thin-film solar panels are expected to be economical to be manufactured due to their reduced costs of material, energy, handling as well as capital. The minimization of the amount of material used, the use of cost effective materials, processing methods and mounting arrays contribute to the achievement of reduction cost of thin film cells.Liquid phase chemical techniques include electrodeposition, chemical bath deposition, iodization and spray pyrolysis. Electrodeposition had been employed to fabricate NiSe2 thin films [1-2].
* Corresponding author. E-mail address: [email protected]
1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the Research Management & Innovation Centre, Universiti Malaysia Perlis doi:10.1016/j.proeng.2013.02.071
556
T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
2. Exprimental Procedures 2.1. Preparation of ITO Coated Glass Substrate and Experimental Setup Ultrasonic cleaner was used to clean up the substrates immersed in ethanol and distilled water, 10 minutes respectively [3]. Then they were dried in mechanical convection oven for 5 minutes.The nickel selenide thin films were prepared from aqueous solutions of nickel sulphate, NiSO4 and sodium selenite, Na2SeO3 acted as a source of Ni2+ and Se2-ions respectively. There were three kinds of electrolyte solutions prepared as specified below. (a) 1.12g NiSO4 powder + 120mL deionised water + 3.12g Na2SeO3 powder + NaOH (b) 1.12g NiSO4 powder + 120mL deionised water + 4g EDTA + 3.12g Na2SeO3 powder + NaOH (c) 1.12g NiSO4 powder + 120mL deionised water + 12mL TEA + 3.12g Na 2SeO3 powder + NaOH Sodium hydroxide was added to acquire the alkaline condition to help the formation of Se2- from Na2SeO3[4]. 2.2. Cyclic Voltammetry (CV), Electrodeposition Experiments and Characterisations Using Princeton Applied Research Model VersaSTAT 3 Potentiostat,cyclic voltammetry (CV) between to common potential limits (-2.00 to 2.00 V) was run to determine the potentials for electrodeposition [5]. The deposition of films was in 30 minutes [2].Figure 1below shows a three electrode cell system adopted for the cyclic voltammetry analysis and deposition of the film.
Fig. 1. The experimental set-up of both cyclic voltammetry and electrodeposition.
Thin film thickness was measured using gravimetric weight difference method. X-ray diffractograms of the thin film was obtained from a PAN analytical XPERT PROMPD PW 3040/60 diffractometer using monochromatic Cu K radiation [6].The morphological analysis of NiSe2 thin film was studied by using optical microscope and JSM-6400 JEOL Scanning Electron Microscope, SEM while compositional study of NiSe2 thin film was conducted using Energy Dispersive X-ray Spectroscopy (EDX). Optical absorption had been studied using Shimadzu 1700 UV-Vis Spectrophotometer in the wavelength region of 200-1100 nm. Zentech A3302-01 Test Leads LCR Meter was used to draw the Mott-Schottky plot. 3. Results and Discussion Fig. 2, 3 and 4 show the cyclic voltammogram of NiSe2in three different environments.
T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
557
Fig. 2. Cyclic Voltammogram of NiSe2 in the absence of additive.
Fig. 3. Cyclic Voltammogram of NiSe2 in the presence of EDTA.
Fig. 4. Cyclic Voltammogram of NiSe2 in the presence of TEA.
Deposition potentials of -1.2, -1.1 and -0.6 V were obtained from Figures 2, 3 and 4 respectively. The current drop indicates the oxidation of nickel compound [7]. The values of thin film thickness at all electrolyte conditions are comparable where the addition of additive in the electrolyte did not give the prominent influence on the thin film thickness as shown in Table 1.
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T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561 Table 1. Thin Film Thickness In Different Electrolyte Condition Sample
Area (cm2)
Mass (×10-3) g
Thin film thickness (×10 -7) m
NiSe2
1.30
0.8
9.158
NiSe2 + EDTA
1.31
0.8
9.088
NiSe2 + TEA
1.29
0.9
10.382
Structural studies were performed at grazing angle incidence (the incidence angle was set at 1.5°) in order to reduce the intensity of the radiation reflected by the substrate [8]. Figure 5 shows the best peaks obtained among the three electrolyte conditions with the formation of desired NiSe2 peaks. The sharp peaks of XRD pattern obtained reveal that the NiSe2 thin films are polycrystalline in nature. (011), (101) and (031) planes that present in the presence of TEA indicate the NiSe2 thin films. The structural features fit into orthorhombic structure of NiSe2 films with lattice parameter values a =0.4890, b = 0.5960 and c = 0.36700 nm which comply with the standard values. Most of the peaks of ITO substrate are only obvious at 30 minutes deposition time. Another film, Ni3Se4 was observed at(002) and (110) planes. NiSe2 thin film deposited in the presence of TEA at 30 minutes deposition timewas chosen to study the surface morphologyand composition due to its best adhesion and well-distribution onto the substrates. The uniformity on the surface area of the film was exposed in 500 times magnifications as shown in Fig. 6 below.
Fig. 5. X-ray diffraction pattern of NiSe2 thin films (in the presence of TEA) deposited at different reposition times.
T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
559
Figure 6. SEM micrographs of NiSe2 obtained as experimental result (40 5 °C, pH 10) at 500 times magnification.
The SEM micrographs shows well-adherent, smooth, and uniform film surface without crack and pinhole [9], [10]. Figure 7 proves the presence of nickel and selenium together with other constituents (Si and O) in composional studies. The presence of silicon is due to the use of ITO coated glass substrates that contain this element while the presence of oxygen is expected from the surrounding atmosphere.
Fig. 7. The EDX analysis of NiSe2 with TEA at 30 minutes deposition time.
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T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
Fig. 8.The plots of (
)2 with respect to photon energy, Eg for nickel selenide thin film in 30 minutes deposition time.
The optical absorption data were analysed from the following classical relation A(hv E g ) n / 2
(1)
hv
where A is a constant between 107 and 108 m-1 , Eg is the energy gap that occupies the area between the bottom of the conduction band and the top of the valence band at the same wave vector K and n is the constant equal to 1 for direct band gap and 4 for indirect gap [11]. The plots of ( )2 with respect to photon energy, Eg for nickel selenide thin film in 30 minutes deposition timeis shown in Figure 8.The band gap values obtained are comparable to the values obtained by the previous researchers which are 1.61 eV of NiSe2 film without additive [12], 2.0 eV of NiSe2 film with TEA [7] and 1.4 eV of NiSe2 with EDTA [6].
Fig. 9. Mott-Schottky plot of NiSe2 in 30 minutes deposition time.
The Mott-Schottky plot drawn in the Figure 9 shows the positive slopes, indicating that the deposited films fall in the ntype conductivity of NiSe2, are negatively charged and have more electrons rather than holes. The intercept of linear plot (1/Ccs2 = 0) was taken as the electrode potential of the semiconductor at whichbond bending is equal to zero [13]. 4. Conclusion Nickel selenide thin films had been successfully deposited onto the indium tin oxide (ITO) coated glass substrate in three different electrolytes by using the potentials obtained from cyclic voltammetry experiment. The use of both TEA and EDTA as the additives had prepared two different electrolytes apart from the one without complexing agent. Structural studies revealed that the films synthesised in the presence of either EDTA or TEA comply the exact stoichiometry of NiSe2. SEM revealed the surface morphology of NiSe2 indicating the formation of microcrystals with the white spots in the dark region.The presence of nickel and selenium had been confirmed via compositional studies.The optical absorption studies have proven that the band gap values obtained fell in the semiconductor region and complied with the values acquired by
T. Joseph Sahaya Anand et al. / Procedia Engineering 53 (2013) 555 – 561
561
the previous researchers. From Mott-Schottky plot, the deposited films fell in the n-type semiconductor, were negatively charged as well as having more electrons rather than holes. Acknowledgement The work described in this paper was supported by Universiti Teknikal Malaysia Melaka (UTeM) and FRGS / KeTTHA sponsored research grant (Project No. FRGS/2011/FKP/TK 02/1 F00120). References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13]
Pathan, H.M. and Lokhande, C.D., 2004. Deposition of metal chalcogenide thin films by successive ionic layer adsorption and reaction (SILAR) method. Bulletin Material Science, 27 (2), pp.85-111. Shariza, S. and Anand, T.J.S, 2011. Effect of Deposition Time on The Structural and Optical Properties of Molybdenum Chalcogenides Thin Films. Chalcogenide Letters, 8 (9), pp.529-539. Anuar, K., Saravanan, N., Wee, T.T., Soon, M.H. and Darren, T., 2010. Chemical Bath Deposition of Nickel Sulphide (Ni 4S3) Thin Films. Leonardo Journal of Sciences, 16, pp.1-12. Zhongbin, Z., Qing, P., Jing, Z., Xun, W. and Yadong, L., 2006. Controlled Hydrothermal Synthesis and Structural Characterization of a Nickel Selenide Series. Wiley Inter Science, 12 (10), pp.211-217. Villamena, F.A., Horak, V. and Crist, R., 2003. Cyclic Voltammetry of Metal Complexes of Nitrones and Nitroxides. Inorganica Chimica Acta, 342, pp.125-130. Anuar, K., Zainal, Z., Saravanan, N. and Kartini, A.R., 2004. Cathodic Electrodeposition and Characterization of Ni 3Se2 thin films. ASTJD, 21 (1), pp.19-25. Zainal, Z., Saravanan, N. and Mien, H.L., 2005. Electrodeposition of Nickel Selenide Thin Films in The Presence of Triethanolamine as a Complexing Agent. Journal of Material Science: Materials in Electronics, 16, pp.111-117. Toma, O., Iftime, S., Besleaga, C., Mitran, T.L., Ghenescu, V., Porumb, O., Toderus, A., Radu, M., Ion, L. and Antohe, S., 2011. New Investigations on Cadmium Sulfide Thin Films for Photovoltaic Applications. Chalcogenide Letters, 8 (12), pp.747-756. Delphine, S.M., Jayachandran, M. and Sanjeeviraja, C., 2005. Pulsed Electrodeposition and Characterization of Molybdenum Diselenide Thin Film. Material Research Bulletin, 40, pp.135-147. Roy, P. and Srivastava, S.K., 2006. Chemical Bath Deposition of MoS2 Thin Film Using Ammonium Tetrathiomolybdate as A Single Source for Molybdenum and Sulphur. The Solid Films, 496, pp.293-298. Ilican, S., Caglar, Y. and Caglar, M., 2008. Preparation and Characterization of ZnO Thin Films Deposited by Sol-gel Spin Coating Method. Journal of Optoelectronics and Advanced Materials, 10 (10), pp.2578-2583. Hankare, P.P., Jadhav, B.V., Garadkar, K.M., Chate, P.A., Mulla, I.S. and Delekar, S.D., 2010. Synthesis and Characterization of nickel selenide thin films deposited by chemical method. Journal of Alloys and Compounds, 490, pp.228-231. Anand, T.J.S., 2009. Synthesis and Characterization of MoS2 Films for Photoelectrochemical Cells. Sains Malaysiana, 38 (1), pp.85-89.