Thin film solar cell based on CuSbS2 absorber prepared by chemical bath deposition (CBD)
Graphical abstract
Introduction
I-III-VI2 semiconductor thin films of ternary compounds have been of big interest because of their potential application in optoelectronics, biotechnology, among others [1], [2], [3], [4]. However, materials such as CIGS despite getting good efficiencies (∼21%) [5], they also have the disadvantage of using Indium that, because of their scarcity, this leads to high costs. That is why the search for materials with suitable properties for their use in solar cells, low cost, low toxicity, and a high abundance on the earth, is very important; these properties could also help scaling the material at an industrial level. CuSbS2 is a semiconductor with a narrow band gap (Eg) [6], [7], this energy value is 1.52 eV, and it’s comparable to the chalcopyrite-type CIGS and kesterite-type CZTS [8], [9], [10], which is close to the optimum value required for solar energy conversion (1.4 eV) and for the potential application of chalcostibite in photovoltaic devices. The CuSbS2 has an orthorhombic crystalline structure (chalcostibite) [11], [12], and also, shows a p-type conductivity in the order of 0.03 (Ω cm)−1.
CuSbS2 has been synthesized by many different methods such as spray pyrolysis [13], [14], thermal evaporation [15], [16], solvothermal [17], thermal diffusion [12], hot-injection [11] and chalcogenization [18]. Recently, the synthesis of CuSbS2 by chemical bath deposition (CBD) has been reported [19], [20]. The CBD method has many advantages, such as simplicity, low energy consumption, and it’s easily scalable to large area applications, among others [21]. In the other hand, the CuSbS2 thin films were incorporated as an absorber layer by different techniques; Lazcano et al. [22], used CuSbS2 in a SnO2:F/(n)CdS/In/(i)Sb2S3/(p)CuSbS2 solar cell, obtaining an open circuit voltage (Voc) of 0.345 V and a short circuit current density (Jsc) of 0.2 mA/cm2. Similarly, Manolache et al. [3], developed a TCO/dense TiO2/CuSbS2/graphite solar cell; in this work, the CuSbS2 was obtained by spray pyrolysis deposition; they obtained a Voc of 0.09 V and Isc of 0.0239 mA. Also, Bo Yang, et al. [23], used CuSbS2 as an absorber layer deposited by spin coating; the solar cell structure was glass/FTO/CuSbS2/CdS/i-ZnO/ZnO:Al, and they obtained a Voc of 0.44 V, Jsc of 3.65 mA/cm2 and η of 0.5% for 0.45 cm2.
In the present work, we report the formation of CuSbS2 thin films by one-step chemical deposition method (CBD) and its characterization by different techniques such as X-ray diffraction (XRD), atomic force microscopy (AFM), UV–vis spectrophotometer, X-ray photoelectron spectroscopy (XPS) and its electrical properties. Additionally, we obtained a solar cell using this material as an absorber layer, and a Voc of 0.382 V and Jsc of 5.324 mA/cm2 for 0.45 cm2, encouraging the future development of this very low cost technology.
Section snippets
Materials and methods
The reagents used for the deposition of CuSbS2 thin films were: SbCl3 (antimony (III) chloride, 99.4%, J. T Baker), C4H8Na2O8 (sodium tartrate, 99.%, Fisher Scientific), C2H6O2 (ethylene glycol, 99.9%, J. T Baker), Na2S2O3∙5H2O (sodium thiosulphate pentahydrate, 99.5%, J. T Baker), C3H8N2S (1,3-dimethyl-2-thiourea, 99%, Aldrich), CuCl2∙2H2O (copper(II) chloride dihydrate, 99%, Fisher Chemicals) and deionized water.
Thin films were chemically deposited on Corning glass substrates with the
Results and discussion
Structural characteristics of the thin films formed at different conditions were analyzed by XRD. Fig. 1 shows the diffraction patterns of the CuSbS2 as deposited and annealed at 350, 380 and 400 °C to 3 mTorr for 1 h. The thin film as prepared, shows a completely amorphous character; however, after heated at 350, 380, and 400 °C, the thin films showed strong peaks of orthorhombic chalcostibite CuSbS2 (JCPDS 44-1417), these peaks corresponds to the (200), (400), (410), (111), (301), (501), (321),
Conclusions
CuSbS2 thin films were prepared on a glass substrate by chemical bath deposition. The structural, chemical, morphological, optical and electrical properties as an absorber layer were investigated. XRD and XPS analysis shows that the chalcopyrite is formed with heat treatment at different temperatures without secondary phases. Thickness around 300–400 nm were obtained with a p-type conductivity using the hot-probe method. A solar cell prepared with this absorber exhibit a maximum conversion
Acknowledgements
The authors thank CONACyT (178228), PAICyT (IT669-11) and Research and development of solar cells with novel materials (CemieSol) for the financial support provided for the development of this research. We also thank Maria Luisa Ramón Garcia (IER-UNAM) for the XRD measurements and PhD. David Avellaneda Avellaneda (FIME-UANL) for the XPS measurements.
References (36)
- et al.
Fabrication and characterization of cost-efficient CuSbS2 thin film solar cells using hybrid inks
Sol. Energy Mater. Sol. Cells
(2016) - et al.
Solvothermal crystal growth of CuSbQ2 (Q = S Se) and the correlation between macroscopic morphology and microscopic structure
J. Solid State Chem.
(2009) - et al.
Growth and vacuum post-annealing effect on the properties of the new absorber CuSbS2 thin films
Mater. Lett.
(2008) - et al.
CuSbS2 thin film formed through annealing chemically deposited Sb2S3-CuS thin films
J. Cryst. Growth
(2001) - et al.
p-Type CuSbS2 thin films by thermal diffusion of copper into Sb2S3
Sol. Energy Mater. Sol. C
(2011) - et al.
The influence of precursor concentration on CuSbS2 thin films deposited from aqueous solutions
Thin Solid Films
(2007) - et al.
Optical and structural properties of CuSbS2 thin films grown by thermal evaporation method
Thin Solid Films
(2009) - et al.
A novel one-step solvothermal route to nanocrystalline CuSbS2 and Ag3SbS3
Solid State Ionics
(1999) - et al.
Formation of CuSbS2 and CuSbSe2 thin films via chalcogenisation of Sb-Cu metal precursors
Thin Solid Films
(2011) - et al.
Effect of deposition variables on properties of CBD ZnS thin films prepared in chemical bath of ZnSO4/SC(NH2)2/Na3C3H5O7/NH4OH
Appl. Surf. Sci.
(2013)
Modification of optical and electrical properties of chemical bath deposited CdS using plasma treatments
Thin Solid Films
Thin films of copper antimony sulfide: a photovoltaic absorber material
Mater. Res. Bull.
Crystallographic and optical properties of CuSbS2 and CuSb(S1-xSex)2 solid solution
Thin Solid Films
Hot-probe method for evaluation of impurities concentration in semiconductors
Microelectron. J.
Study on the synthesis and formation mechanism of flower-like Cu3SbS4 particles via microwave irradiation
J. Alloys Compd.
Two-stage co-evaporated CuSbS2 thin films for solar cells
J. Alloys Compd.
Tuning the luminescence properties of colloidal I-III-VI semiconductor nanocrystals for optoelectronics and biotechnology applications
J. Phys. Chem. Lett.
Structural, optical and electrical properties of CuSbS2 these amorphous films: effect of the thickness variation
Chalcogenide Lett.
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