Cu2SnS3 Thin Films Research Articles

Influence of sulfurization process in tin sulfide and sulfur mixed vapors on the morphology of Cu2SnS3 thin films

Abstract Cu2SnS3 (CTS) is expected to be an absorber material for next-generation solar cells because it is composed of nontoxic, low-cost elements and has an absorption coefficient of >104 cm−1. In this study, the effects of sulfurization in tin sulfide (Sn x S y ) and S mixed vapors on various properties of CTS were investigated by using a 3-zone tube furnace to suppress carrier recombination at the grain boundaries and control the composition of the CTS. The CTS deposited via sulfurization in S vapor only (1-zone CTS) contained different monoclinic and tetragonal CTS structures. The grain size of the CTS thin films deposited via sulfurization in Sn x S y and S mixed vapors was not increased. On the other hand, crystal structure analysis revealed that the CTS had grown to single-phase monoclinic CTS. The results suggest that precipitation in Sn x S y and S mixed vapors contributes to the growth of monoclinic CTS with suitable power-generation characteristics. This finding is important for realizing high-efficiency CTS-based solar cells.

A preliminary investigation into the potential of Ge-enhanced Cu2SnS3 (CTS) thin-film applications for water-splitting photoelectrodes

This study explores the potential of Ge-enhanced Cu2SnS3 (CTS) thin-films as photoelectrode materials for water splitting grown through a simple sulfurization process. The addition of Ge to CTS enabled tuning the bandgap and improved the photocurrent density. Films sulfurized at 520 °C exhibit enhanced grain size and reduced grain boundaries, which contribute to increased carrier transport efficiency. By optimizing Ge content and sulfurization conditions, the Cu2(Sn1−x ,Ge x )S3 films demonstrate promising capabilities for efficient green hydrogen production. This work lays the groundwork for developing advanced photoelectrodes and highlights the need for further refinement to maximize performance for practical applications.

Effect of deposition time on the physicochemical properties of co-electrodeposited Cu2SnS3 thin films for photovoltaic applications

This study highlights our optimization of the co-electrodeposition duration of Cu, Sn, and S on the titanium substrate in order to further improve the properties of Cu2SnS3 thin films in photovoltaic applications. After cyclic voltammetry identifying the potential for simultaneous Cu, Sn and S deposit, "Cu–Sn–S″ layers were electrodeposited for deposition durations ranging from 10 → 20 min. Structurally, X-ray-diffraction and Raman-spectroscopy have confirmed the formation of the single Cu2SnS3-phase, crystallizing in the triclinic system after 20 min of electrodeposition. For this duration, the morphological SEM-EDX profile revealed a highly uniform distribution of grains with very optimal sizes for solar cell applications. To reinforce these conclusions, an optical analysis was carried out in the visible wavelength range, highlighting a strong absorption of the developed sample. In addition, the optical gap estimate, indicates that Cu2SnS3 exihibts a direct transition with a bandgap varying from 1.22 to 1.49eV when the deposition time is increased from 10 →20 min.

Current Remedy in Ultrathin Crystalline Si Solar Cell by Cu2SnS3 Thin Film toward High Efficiency

An ultrathin 15 μm wafer‐based c‐Si solar cell is designed and simulated, wherein the current remedy is done by Cu2SnS3 (CTS) thin film. The ZnSe and AlSb are incorporated as window and back surface field (BSF) layers, respectively, in this model. The ultrathin Si‐based n‐ZnSe/p‐Si exhibits the short‐circuit current density of 30.66 mA cm−2 with an efficiency of 18.80%. The inclusion of p+‐CTS thin film as a second absorber layer has enhanced this current to 42.14 mA cm−2. By absorbing sunlight up to 1200 nm, the CTS layer is able to successfully overcome the constraint of thinner Si wafers on longer‐wavelength photon absorption leading to current augmentation. The addition of p++‐AlSb as the BSF layer also boosts the open‐circuit voltage by 300 mV. The rise in VOC is a result of the larger built‐in potential in ZnSe/Si, Si/CTS, and CTS/AlSb interfaces. With enriched current and voltage, the final proposed n‐ZnSe/p‐Si/p+‐CTS/p++‐AlSb heterostructure theoretically records an efficiency of 35.48% in ultrathin Si solar cells. The current compensation obtained using CTS thin film in this work can give optimism about the future of ultrathin Si solar cells.

Formation and detection of secondary crystalline phases in Cu2SnS3 thin films for photovoltaic applications

Formation and detection of secondary crystalline phases in Cu2SnS3 thin films for photovoltaic applications

Theoretical exploration of high VOC in Cu2SnS3 thin film solar cells towards high efficiency

This article manifests the outstanding performance of copper-tin-sulphide (Cu2SnS3)-based double-heterojunction (DH) photovoltaic cell. The n-type ZnSe as window and the p+-type CGS (CuGaSe2) as back surface field (BSF) layer have been used for the p-type Cu2SnS3 base layer. The SCAPS-1D simulator is used for the simulation of this photovoltaic cell and demonstrating the effects of each layer. The n-ZnSe/p-Cu2SnS3 heterojunction has displayed a power conversion efficiency (PCE) of 17.69 % with JSC = 32.39 mA/cm2, VOC = 0.60 V, and FF = 80.58 %, when functioning alone. An enrichment of PCE to 38.14 % has been observed, owing to the addition of CGS as aBSF layer in the proposed structure. The VOC also develops enormously to 1.22 V in dual-heterojunctions, which boosts the PCE. The effective band alignment between ZnSe/Cu2SnS3 and Cu2SnS3/CuGaSe2 interfaces produces greater built-in potential that is liable to generate high VOC. The built-in potential of the device is 1.54 V according to the C-V study. These outcomes imply that the n-ZnSe/p-Cu2SnS3/p+-CGS device would be a viable alternative for harvesting solar energy in the era of thin film solar cells.

A one-step electrodeposition method was used to produce monoclinic Cu2SnS3 thin films for the development of solar cells

A one-step electrodeposition method was used to produce monoclinic Cu2SnS3 thin films for the development of solar cells

Effect of cover annealing on Cu2SnS3 thin films deposited by dual-source fine-channel mist chemical vapor deposition

Effect of cover annealing on Cu2SnS3 thin films deposited by dual-source fine-channel mist chemical vapor deposition

Cu2SnS3 based photovoltaic structure with improved open circuit voltage for air stable self-driven enhanced NIR photodetection

Copper tin sulfide (Cu2SnS3) is an environmentally benign and economical semiconductor comprising earth-abundant, non-toxic elements with flexible optoelectronic properties for photovoltaic energy conversion and photodetection. The optimization of sulfurization temperature resulted in significant improvement in structure, morphology, elemental composition, optical and electrical properties. A substantial advancement in photovoltaic performance was achieved by integrating a thin layer of SnS and the same enhancement theoretically predicted using SCAPS-1D simulation. Photovoltaic structure with optimized monoclinic Cu2SnS3 as an absorber layer and thin SnS layer (Glass/FTO/CdS/SnS/Cu2SnS3/Ag) resulted in photovoltaic parameters: Voc = 415 mV, Jsc = 17.2 mA.cm−2, and PCE = 2.12 %. We demonstrate the first self-powered SnS/Cu2SnS3 based photodetector which delivers high detectivity of 1.41 × 1011 Jones under the illumination of an 840 nm laser with rapid rise and decay time of 10.2 and 10.1 ms, respectively. Economic and environmentally benign Cu2SnS3 thin films based photovoltaic structures will be beneficial for harvesting sustainable energy and paving a strong platform for self-powered, air-stable, and spectral selective photodetection.

Effect of Ge doping on the material properties of sprayed Cu2SnS3 thin films

A facile spray pyrolysis processing of ternary Cu2SnS3 and Cu2Sn1−xGexS3 absorbers is presented. The Cu2SnS3 and Cu2Sn1−xGexS3 thin films were sprayed onto both glass and Mo substrates at 350 °C and then annealed at 550 °C with S and SnS/GeS crystals. The impacts of germanium incorporation on the properties and solar cell device performance of the Cu2SnS3 layers were studied. X-ray diffraction and Raman measurements confirmed the monoclinic crystal structure of both Cu2SnS3 and Cu2Sn1−xGexS3 layers, with a slight peak shift observed in the Cu2Sn1−xGexS3 samples due to the substitutional incorporation of Ge into the Sn site in the Cu2SnS3 lattice. The introduction of Ge also increased the optical bandgap from 0.93 eV for Cu2SnS3 to 0.99 eV for Cu2Sn1−xGexS3 samples. Furthermore, Cu2Sn1−xGexS3 layers exhibited enhanced grain growth, leading to an improved device performance from 1% for Cu2SnS3 to 2.1% for Cu2Sn1−xGexS3 solar cells.

Tuning Thermoelectric Properties of Spin-Coated Cu2SnS3 Thin Films by Annealing

Tuning Thermoelectric Properties of Spin-Coated Cu2SnS3 Thin Films by Annealing

Enhancement of grain growth in Cu2SnS3 thin films prepared by the addition of Au and fabrication of solar cells using Au-added CTS thin films

Cu2SnS3 (CTS), obtained by depositing Au on an Sn/Cu metal stacked precursor fabricated by electron beam deposition and sulfurization, was investigated. In thin films obtained by sulfurization at 560 °C of the precursor with SLG/Mo/Sn/Cu/Au/NaF structures fabricated on Soda lime glass substrates containing alkali metals, a significant increase in the CTS grain size was observed in the Au deposition thickness range of 5–25 nm. By contrast, no crystal growth was observed in thin films with a precursor without an NaF layer fabricated using alkali-free glass (EAGLE XG), regardless of the thickness of the Au-deposited film. Therefore, appropriate amounts of Au and Na promote the crystal growth of CTS. In addition, at the sulfurization temperature of 570 °C, the crystal grains were larger than those of the thin film fabricated at 560 °C. In the fabricated CTS thin-film solar cells, with a sulfurization temperature of 570 °C and an Au deposition thickness of 10 nm, open circuit voltage of 0.261 V, short circuit current density of 25.4 mA cm−2, fill factor of 0.425, and a power conversion efficiency of 2.82% were obtained.

Photoluminescence properties of Cu-poor Cu2Sn1− x Ge x S3 thin films with varying Ge/(Ge+Sn) ratio

This study investigates the photoluminescence (PL) spectra of Cu2Sn1−x Ge x S3 (CTGS) thin films, which are currently the most suitable composition ratio for high-efficiency absorbers through low temperature-PL measurements to reveal the effects of the x ratio on defect properties of CTGS thin films. The PL spectrum of Cu2SnS3 (CTS) thin films with x= 0.00 exhibits five peaks at 0.782, 0.832, 0.862, 0.885, and 0.933 eV. Moreover, all PL peak positions in the CTGS thin films shift to higher energies with increasing x ratios because the defect levels in the films changed with an increase in the x ratio. Moreover, we obtain the estimated activation energy (E a) values of the CTS thin films with x = 0.00 ranging from 6 to 20 meV. The E a values of CTGS are similar to those of the CTGS thin films, even at x ratios of up to 0.19 in CTGS thin films. The increasing x ratio in CTGS thin films does not influence the acceptor in CTGS. Therefore, the CTGS is advantageous as an absorption layer in solar cells rather than a CTS because E g can be large while maintaining a shallow acceptor. Hence, CTGS can be expected to be increasingly used like CuIn1−x Ga x Se2 and Cu2ZnSnS4 as next-generation absorption materials.

Review on ternary chalcogenides: Potential photoabsorbers

The development of photovoltaic technology has brought in clean energy production. However, silicon is the most commonly used semiconductor in photovoltaics with power conversion efficiency (PCE) of about 18% to 22% under standard conditions. Recently, the chalcopyrite structure of I-III-VI2 constitutes ternary chalcogenides and the subsequent thin films are being used in second generation thin film solar cells (TFSC). Copper-based (Cu-III-VI2) and silver-based (Ag-III-VI2) chalcogenides are emerged as alternatives for toxic elements & lowcost in optoelectronics. In particular, Copper Indium Diselenide (with the optical band gap of 1.04 eV) cells have up to 14% efficiency with similar durability as silicon solar cells. Similarly, the optical band gap of Cu2SnS3 (CTS) thin films is 1.23 eV and the absorption coefficient is > 105 cm−1 and hence act as potential photoabsorber in TFSC. AgGaSe2 and AgGaTe2 have a direct band gap of 1.42 eV and 0.75 eV, respectively, and strong clarity in the 500–1200 nm wavelength range. Also, the optical properties of Ag-based chalcogenides (AgAlS2) are equivalent to those of Cu-based chalcogenides (CuAlS2). Similarly, a number of ternary semiconductors, including CuInS2, CuSnSe2, CuSbS2, AgInSe2, AgGaS2 and AgBiS2 with a bandgap in visible regions are created with rich crystal structures and high absorption coefficients using various deposition techniques, making them well suited for photoabsorbers. Herein, the latest progress of ternary chalcogenides is reviewed from the aspects of synthesis, characterization, and properties. In addition, their potential in optoelectronic devices is also discussed.

Investigation on photovoltaic performance of Cu2SnS3 thin film solar cells fabricated by RF-sputtered In2S3 buffer layer

A two-step process was used to prepare Cu2SnS3 films in this study: first, precursor stacks were deposited using a magnetron sputtering technique, and then the stacks were annealed in sulfur-containing atmosphere at various times. Utilizing a variety of characterization techniques, it was thoroughly examined how sulfurization time affected the films’ structural, morphological, optical, and electrical characteristics. X-ray diffraction and Raman spectroscopy measurements indicated that two structural polymorphs (tetragonal and monoclinic) of Cu2SnS3 co-existed in the films. Surface and cross-sectional images obtained by scanning electron microscopy showed that the microstructures of the films were entirely changed to well-grown crystal structures at 30 min and 40 min sulfurization times. In2S3/Cu2SnS3 stacks were prepared by the deposition of In2S3 films on the absorber layers sulfurized for 30 and 40 min by RF magnetron sputtering method. The fabrication of Ni/Al/Ni/AZO/i:ZnO/In2S3/Cu2SnS3/Mo/SLG-structured devices was done using both thermally annealed and non-annealed In2S3/Cu2SnS3 stacks. Secondary ion mass spectroscopy studies of the devices revealed that the indium diffused from In2S3 layer into the Cu2SnS3 absorber to a certain depth. The efficiency values of the devices were found to have been slightly enhanced with the annealing of the In2S3/Cu2SnS3 stacks. The solar cell with the maximum efficiency (η) of 3.12 %, open-circuit voltage (VOC) of 0.265 mV, short-circuit current (JSC) of 37.90 mA/cm2, and fill factor (FF) of 0.31 was produced by thermally annealed In2S3/Cu2SnS3 stack with an absorber layer sulfurized for 40 min.

Non hydrazine based chemical synthesis of earth abundant Cu2SnS3 thin film photocatalyst for wastewater treatment

Utilization of renewable solar energy has been a vital achievement for material scientists. The present work represents synthesis of Cu2SnS3 (CTS) thin film photocatalysts by a simple and economical spin coating sol gel method. The films were investigated for their structural, morphological, compositional, optical and chemical properties. Monoethanolamine (MEA) was employed to enhance the age of CTS gel by increasing its stability. X-ray diffraction (XRD) and Raman analysis indicated formation of single phase pristine tetragonal CTS material. Morphological studies showed the films are covered with CTS quantum dots. X-ray photoelectron spectroscopy (XPS) revealed oxidation states of Cu, Sn and S as +1, +4 and −2 respectively. The CTS material exhibited polycrystalline nature determined from the selected area electron diffraction (SAED) patterns of the films. The films has optimum energy band gap (∼1.7 eV) suitable for visible light photocatalysis. The thin films were explored as photocatalysts against methylene blue (MB) dye and it was found that the films degraded most of the dye (∼87%) in just 90 min of visible light illumination. Reusability experiments performed showed the films can be used again and again without considerable loss in the activity.

Correlation between some physical properties of pure and Sb doped Cu2SnS3 thin films under the effect of sulfur amount for solar cell application

Adjusting of sulfur content and amount of doping in Cu2SnS3 (CTS), as absorber layer for solar cell, is a promising approach to fabricate thin film solar cells with high performance. In this work, the effect of different amounts of sulfur in the sulfurization process and the percentage of Sb doping in the films were studied. The physical properties of un-doped and doped CTS thin films were investigated. The pure and doped CTS thin films showed a monoclinic structure, with a larger grain size under the influence of Sb doping. XPS analysis demonstrated that Cu, Sn, S, and Sb oxidation states were +1, +4, −2, and +3, respectively. The Sb-doped sample for 25 min (25Sb) has a higher Cu+1/Cu+2 ratio than other samples and no satellite peak of Sn+2 was observed as compared to other levels of doping samples. This concluded that the Cu species in the 25Sb film experienced a more Cu-rich chemical environment. Both PL and UV–Vis spectroscopy were used to obtain the optical properties. Hall Effect was applied to measure the electrical properties of un-doped and doped CTS films. The pure and Sb-doped CTS solar cells were fabricated by optimization of Sb doping time and sulfur amount. The conversion efficiency of the prepared solar cell was 2.13% when fabricated with CTS layer that treated with 25 min of Sb doping and 100 mg of sulfur, whereas the efficiency of the un-doped CTS solar cell at the same sulfur amount was just 0.615%.

Fabrication of Cu2SnS3 thin films by dual-source fine channel mist CVD

Fabrication of Cu2SnS3 thin films by dual-source fine channel mist CVD

Elucidation of electrical properties of undoped and Sb-induced Cu2SnS3 (CTS) thin films and degradation properties on CTS thin films and solar cells by intentional proton irradiation

The fundamental electrical properties of undoped and Sb-induced Cu2SnS3 (CTS) thin films were evaluated. Furthermore, the relationship between defect properties during intentional degradation and thin film/solar cell properties was investigated. The carrier concentration decreased after Sb induction in the CTS film, and the resistivity increased by one order of magnitude. These values were independent of the Sb volume. These results imply that a small quantity of Sb atoms passivates the defects, such as Sb atoms at Sn or Cu sites that compensate for the intrinsic acceptors at Cu vacancies. In addition, the number of defects around the grain boundary tended to decrease with Sb induction because of passivation. The carrier concentration of the CTS layer remained unchanged following proton irradiation at 1 × 1014 cm−2. Furthermore, the number of defects increased, independent of the Sb induction.

MODELLING OF THE SOLAR CELL BASED ON Cu2SnS3 THIN FILM PRODUCED BY SPRAY PYROLYSIS

Cu2SnS3 (CTS) thin film has been produced for 30 ccm sulphur flux rate at 30 minutes annealing durations at 550 oC temperature. CTS thin film’s crystalline structure has been investigated and crystalline size, lattice parameters, dislocation density and microstrain, crystalline number have also been determined. The CTS thin film’s morphological and optical properties have been examined and thoroughly interpreted. Mo/CTS/CdS/AZO solar cell has been modelled based on CTS thin film produced at the present work, using SCAPS-1D simulation programme. Voc, Jsc, FF, conversion efficiency and photovoltaic parameters have been determined depending on neutral defect density at the interface, coefficient of radiative recombination, Auger electron/hole capture’s coefficient and operation temperature of CTS solar cell. As a consequence of simulation study, ideal efficiency of CTS solar cell has been determined to be 3.72 % and all the data obtained in this study have been presented, interpreted and concluded to be original results.