Facile synthesis and optical properties of pure and Ni²⁺, Co²⁺, Bi³⁺, Sb³⁺ substituted Cu₃SnS₄

Abstract

Cu₃SnS₄ in an orthorhombic symmetry has been stabilized by a simple and one pot synthesis involving the reaction of thiourea complexes of copper and tin. The obtained product has been characterized thoroughly using high resolution powder X-ray diffraction (PXRD), SEM-EDX, Raman, UV-vis-NIR, and photoluminescence spectroscopy measurements. The presence of bands at 282, 317, 333 and 346 cm⁻¹ in the Raman spectrum conclusively confirmed the orthorhombic symmetry of Cu₃SnS₄. Adopting this synthetic strategy, quaternary compositions consisting of nickel, cobalt, antimony and bismuth have been synthesized and characterized by all physico-chemical techniques. Of all these, compositions containing bismuth and antimony in place of tin are quite original and are reported for the first time. While the nickel substitution retained the orthorhombic symmetry, cobalt substitution resulted in tetragonal symmetry for the quaternary composition. Similarly, the presence of bismuth ions in the lattice preserved the orthorhombic symmetry and the PXRD pattern of the product containing Sb³⁺-ions could be indexed to tetragonal symmetry. The homogeneous distribution of all these elements in the samples was verified from a scanning TEM technique. The band gaps of the pure and Ni²⁺, Co²⁺, Bi³⁺ and Sb³⁺substituted Cu₃SnS₄ compositions, determined from the UV-vis-NIR absorbance data, were in the range of 0.9–1.46 eV. This is ideally suited for the use of these materials in photovoltaic cells.

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1. Introduction

Band gap engineering in semiconductors to equip them for suitable applications has been extensively investigated.¹ Among the chalcogenide based semiconductors, studies on the inexpensive, non-hazardous, non-toxic compositions of Cu–Sn–S are being conducted for energy related applications including solar cells.² The three known phases in the Cu–Sn–S system, viz., Cu₂SnS₃, Cu₃SnS₄ and Cu₄SnS₄ possess structures derived from the ZnS structure.³ Owing to its suitable band gap, orthorhombic Cu₃SnS₄ can be a potential light absorption material for solar cells.⁴ The enormous structural diversity shown by Cu₃SnS₄ offers enough opportunities for chemists to design new greener synthetic methodologies that are preferably one-step, without using toxic solvents, cheaper methods and simpler (easier) reaction conditions. In Cu₃SnS₄, a hexagonally closed packed sulfur anionic network is present in which cations occupy half of the tetrahedral interstices. From the band structure calculations, the valence band maximum (VBM) of Cu₃SnS₄ has been estimated to consist of antibonding component of hybridization between Cu d states and S p states, while the conduction band minimum (CBM) included mainly the antibonding component of hybridization between Sn s and S s states.⁵ This distinction is quite advantageous to tune the band gap by substituting with suitable cations either at the copper site or at the tin site in Cu₃SnS₄. Incorporation of fourth metal ion into Cu₃SnS₄ system leads to the quaternary compositions Cu₂MSnS₄ showing ideal absorption characteristics in the visible region to be used in solar cells.^6–8 For example, by the appropriate choice of fourth metal ion, one can impart additional optical, photochemical, thermoelectric and magnetic functions.^7,8 The structural flexibility offered by quaternary compositions provides additional advantage to engineer them for suitable applications. Considering Cu₃SnS₄ as Cu₂CuSnS₄, replacing the copper with other transition metal ions such as Co²⁺, Ni²⁺, Fe²⁺ and Zn²⁺ resulting in quaternary compositions Cu₂MSnS₄ have been attempted.⁹ Cu₂CoSnS₄ (CCTS) has been fabricated in all the three different arrangements of zincblende (cubic), tetragonal and wurtzite (hexagonal) by following solution based synthetic routes (solvothermal approach) with and without the use of surfactants.^9a,10 As compared to CCTS, very few literature reports exist on the successful synthesis of Cu₂NiSnS₄ (CNTS) and their properties. While wurtzite arrangement resulted CNTS from the solvothermal reaction of CuCl, SnCl₂·2H₂O Ni(NO₃)₂·6H₂O and 3-mercaptopropanoic acid in a coordinating solvent hexylamine,^9a zincblende form was obtained when the sulfur source and the solvent changed to thiourea and ethyleneglycol, respectively.^8b The variations in the symmetry of final products demonstrated the complex relation between the nature of reactants, nature of solvent and the mode of synthesis in addition to the challenge of preventing the formation of thermodynamically stable binary sulfides.^8b,9–13 Metal–thiourea precursors have been demonstrated to be versatile in generating not only various compositions of Cu–S system but also in stabilizing metastable ternary phases of CuInS₂ and CuFeS₂ in ethyleneglycol.¹⁴ The present study is aimed to generate Ni²⁺, Co²⁺ (transition metals) substituted for Cu²⁺-ions and Bi³⁺ and Sb³⁺ (p-block elements) substituted for Sn⁴⁺ of Cu₃SnS₄ by a simple, one step procedure in a less coordinate solvent (ethyleneglycol) with the simultaneous understanding of their role on the choice of symmetry, structure and the optical properties of the final products. The obtained results are discussed below.

2. Experimental

2.1 Synthesis of precursors

(i) Synthesis of [Cu(tu)₃]Cl. [Cu(tu)₃]Cl was obtained by reacting 0.099 g (1 mmol) of freshly prepared CuCl with 5 ml aqueous solution containing 0.2284 g (3 mmol) of thiourea (Spectrochem, 98%) under constant stirring over a period of 30 minutes.¹⁵ After the reaction, the solution was filtered to remove any unreacted solid and crystallized at room temperature. To get the sufficient quantity of the complex, the reaction was repeated several times.

(ii) Synthesis of [Sn(tu)]Cl₂. 1.1282 g of SnCl₂·2H₂O (Sigma Aldrich, 99.99%) was dissolved in a minimum amount of 5 M HCl solution. A solution of thiourea (0.3806 g in 10 ml) was added drop wise to SnCl₂·2H₂O solution under constant stirring.¹⁶ The complex formed was dried naturally.

(iii) Synthesis of [Ni(tu)₄]SO₄. 1.1417 g of thiourea was dissolved in a minimum amount of water (15 ml) under constant stirring over a magnetic stirrer. To a 10 ml aqueous solution containing 1.3137 g of nickel(II) sulfate (Qualigens, AR Grade), thiourea solution was added drop wise under constant stirring and continued for 1 h.¹⁷ After evaporation, the green colored crystals were collected.

(iv) Synthesis of [Co(tu)₂]Cl₂. 0.7612 g of thiourea was dissolved in a minimum amount of water (15 ml) with constant stirring over a magnetic stirrer. To a 10 ml aqueous solution containing 1.1896 g of cobalt(II) chloride (CDH, 99%), thiourea solution was added drop wise under constant stirring. The reaction was continued for 1 h, after which, blue colored crystals were obtained.^18,19

(v) Synthesis of [Bi₃(tu)₃]Cl₃. 2.3298 g of bismuth oxide (Bi₂O₃, Sigma Aldrich, 99.99%) was dissolved in 20 ml of 5 M HCl, to which 10 ml aqueous solution containing 1.5224 g of thiourea was added drop wise.²⁰ The reaction mixture was stirred for 3 h and transferred to a Petri dish and evaporated.

(vi) Synthesis of [Sb(tu)₂]Cl₃. 1.4576 g of antimony oxide (Sb₂O₃, Sigma Aldrich, 99.99%) was dissolved in 20 ml of 5 M HCl, to which 10 ml aqueous solution containing 1.5224 g of thiourea was added drop wise. After stirring for 3 h at room temperature, the complex was transferred and dried in a Petri dish.²¹

2.2 Synthesis of Cu–M–Sn–S compositions

0.9825 g of [Cu(tu)₃]Cl (3 mmol) and 0.2651 g of [Sn(tu)]Cl₂ (1 mmol) were mixed well in the solid state to which in 50 ml of ethyleneglycol (Merck, AR Grade) was added. Within few minutes of refluxing, the solution turned brown in colour. But the reaction was continued for 1.5 h. The product after the reaction was separated by centrifugation and washed repeatedly with double distilled water, ethanol and carbon disulphide. The sample was dried naturally at room temperature. Ni²⁺, Co²⁺, Bi³⁺ and Sb³⁺ substitutions were attempted by simple refluxing of 0.4592 g (1 mmol) [Ni(tu)₄]SO₄/0.2865 g (1 mmol) [Co(tu)₂]Cl₂/0.3208 g (0.33 mmol) [Bi₃(tu)₃]Cl₃/0.3806 g (1 mmol) [Sb(tu)₂]Cl₃ with 0.6548 g (2 mmol) of [Cu(tu)₃]Cl and 0.2651 g (1 mmol) of [Sn(tu)]Cl₂ in 50 ml of ethyleneglycol for 3 h. The product was separated by centrifugation, washed with double distilled water followed by ethanol and carbon disulfide.

2.3 Characterization

Powder X-ray diffraction (PXRD) patterns were recorded using PANalytical Empyrean diffractometer, equipped with PIXcel^3d detector, employing Cu K_α radiation (λ = 1.5418 Å) with scan step size of 0.01313° and 188.44 seconds per step. UV-vis-NIR absorbance spectra of the samples were collected using a Thermo Scientific UV-vis-NIR spectrophotometer (Model Evolution 300) equipped with an integrating sphere by dispersing them in n-hexane. Raman spectrum in compact form was collected using a Renishaw via Microscope system with a diode laser (λ = 785 nm). Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED) were carried out on an FEI Technai G² 30 electron microscope operating at 300 kV. Scanning electron microscopic (SEM) images were captured using a Zeiss EVO 50 microscope and FE-SEM Quanta 200 FEG microscope equipped with EDS detector. Elemental mapping of the samples was surveyed with JEOL 6610LV Scanning Electron Microscope. Photoluminescence spectroscopy measurements were carried out on the Horiba Jobin Yuvon Fluorolog-3 modular spectrofluorometer at room temperature employing CW xenon lamp source on solid samples using front side and right angle detection configuration.

3. Results and discussion

As metal–thiourea complexes have been used as the starting materials, their formations have been confirmed from FTIR, Raman spectroscopic analysis. The positions of FTIR bands of the reaction of one mole of CuCl with three moles of thiourea were present at 1477, 1389, 1093 and 710 cm⁻¹ showing significant change from the position of bands for free thiourea (1473 (ν(CN)), 1414 (ν(CS)), 1083 (ν(CN)) and 730 cm⁻¹ (ν(CS))) (Fig. S1 ESI†).¹⁵ In the Raman spectrum, bands at 150, 200, 420, 475 and 707 cm⁻¹ were present suggesting the formation of complex in 1 : 3 between CuCl and thiourea.²² The presence of characteristic bands in the FT-IR and Raman spectra indicated the formation of 1 : 1 complex of SnCl₂·2H₂O and thiourea (Fig. S2 ESI†).¹⁶ Similarly, complex formation between NiSO₄·6H₂O and thiourea in 1 : 4 stoichiometry was confirmed from its finger print positions (478 cm⁻¹ and 734 cm⁻¹) in the Raman spectrum (Fig. S3 ESI†).¹⁷ Similar confirmation for the 1 : 2 complex between CoCl₂·6H₂O and thiourea was sought from its Raman spectrum (Fig. S4 ESI†).¹⁹ While both FT-IR and Raman spectra confirmed the formation of [Sb(tu)₂]Cl₃, band positions at 1623, 1379, 1094 and 693 cm⁻¹ in the FT-IR spectrum indicated the formation of [Bi₃(tu)₃]Cl₃ (Fig. S5 and S6 ESI†).^20,21

PXRD pattern of the solid product from the reaction of copper and tin thiourea complexes is presented in Fig. 1a(i). All the observed reflections could be indexed in an orthorhombic unit cell with a = 6.787 (44) Å, b = 7.728 (78) Å and c = 37.555 (33) Å. These values are close to the reported values in the JCPDS file no. 36-0217. The average crystallite size (D) of the sample, estimated from the Scherrer analysis was 3 nm. Uniform spherical morphology was observed across the analyzed area of the sample by SEM. Ratio of Cu, Sn and S from EDX analysis was as 3.1 : 0.9 : 4, closer to the composition of Cu₃SnS₄ (Fig. S7 ESI†). The presence of bands at 282, 317, 333 and 346 cm⁻¹ in the Raman spectrum conclusively confirmed the orthorhombic symmetry of Cu₃SnS₄ (Fig. 2a).^4,23 The sample showed absorption in whole of the visible range in the UV-vis-NIR absorption spectrum and the Tauc plot ((αhν)² versus hν), yielded a band gap of 1.21 eV (Fig. 2b and c). This is less than the theoretically calculated value of 1.6 eV.⁴ This deviation might be due to quantum confinement arising from the nanosized crystallites. When excited with 270 nm, Cu₃SnS₄ showed two emission bands at 417 and 439 nm respectively (Fig. 2d). Band at 439 nm might be the electron hole recombination band and the one at 417 nm might be arising from 3d⁹ 4s¹ ↔ 3d¹⁰ transition of Cu⁺ ion.^24,25.

Fig. 1 (a) PXRD pattern of (i) Cu₃SnS₄ (red) and (ii) Cu₂NiSnS₄ (blue) and (b) scanning TEM image of Cu₂NiSnS₄.

Fig. 2 (a) Raman spectrum (b) UV-vis-NIR absorption spectrum (c) band gap estimation plot and (d) photoluminescence emission spectrum of Cu₃SnS₄ (red square) and Cu₂NiSnS₄ (blue circles) at λ_exc = 270 nm.

PXRD pattern of the product, from the reaction of thiourea complexes of copper, nickel and tin is presented in Fig. 1a(ii). It showed close resemblance to the PXRD pattern of orthorhombic Cu₃SnS₄ with the observed reflections showing no significant shift in the two-theta positions. From the Le Bail refinement, the determined lattice constants were a = 6.581 (18) Å, b = 8.104 (31) Å and c = 37.754 (95) Å. Incorporation of Ni²⁺ for Cu²⁺ in Cu₃SnS₄ was not clear from PXRD results. Use of other techniques, such as STEM, Raman spectroscopy and SEM-EDX analysis was sought for the verification of uniform inclusion of nickel in Cu₃SnS₄. The ratio between Cu : Ni : Sn : S, from EDX analysis was 2.5 : 0.9 : 0.9 : 3.7 (Fig. S8 ESI†). STEM-HAADF image and corresponding EDS elemental maps (shown in Fig. 1b) depicted homogeneous distribution of the four elements in the sample. The scanning SEM images also validated the homogeneity of the sample at micro-crystalline level (Fig. S9 ESI†). Raman spectrum of nickel substituted Cu₃SnS₄ is shown in Fig. 2a in which peak broadening is observed arising from the phonon confinement. It was deconvoluted to yield three peaks at 282, 311 and 348 cm⁻¹ (Fig. 2a). In the UV-vis-NIR spectrum, a broad band starting from visible region and extending up to infra-red region was observed for the sample (Fig. 2b). Estimated band gap from the Tauc plot was 1.46 eV, higher than the value observed for Cu₃SnS₄ (Fig. 2c). Single broad emission occurring in the ultraviolet region was noticed in the PL spectrum on exciting it with λ = 270 nm (Fig. 2d). As noted earlier, this could be a recombination band.²⁴ SAED patterns of this phase are displayed in Fig. S10 (ESI†). The observed spots in the SAED pattern could be indexed to orthorhombic unit cell corresponding to [202̄0̄], [201̄2̄], [001̄2̄] and [001̄0̄] hkl planes.

In Fig. 3a, PXRD pattern of the product from the reaction of Cu–Co–Sn–tu complexes in 2 : 1 : 1 molar ratio is presented. All the observed reflections could be indexed in tetragonal symmetry following the JCPDS card no. 26-0513 with the composition, Cu₂CoSnS₄. The lattice constants from the Le Bail refinement were a = 5.471 (13) Å and c = 11.663 (51) Å. EDX analysis confirmed the presence of cobalt in the samples yielding a ratio of 2.4 : 0.6 : 0.7 : 4.2 for Cu : Co : Sn : S (Fig. S11 ESI†). Elemental mapping confirmed the uniform presence of all the constituent elements across the cross-section of samples (Fig. 3b). Room temperature Raman spectrum of this sample is shown in Fig. 4a. On deconvolution, bands at 288, 320 and 347 cm⁻¹ have been observed. Band positions were matching well with earlier reports.^10a Fig. 4b represents UV-vis-NIR absorbance spectrum of Co-substituted Cu₃SnS₄ with absorption edge near 900 nm. The estimated band gap value was 1.23 eV (Fig. 4c). Photoluminescence emission spectrum, obtained using excitation wavelength of 270 nm, showed a small hump at 330 nm arising from the Co²⁺-ion in the tetrahedral coordination with sulphur (Fig. 4d).²⁶ This feature also conclusively confirmed the introduction of cobalt in Cu–Sn–S network.

Fig. 3 (a) PXRD pattern and (b) scanning SEM image of Cu₂CoSnS₄.

Fig. 4 (a) Raman spectrum (b) UV-vis-NIR absorption spectrum (c) band gap estimation plot and (d) photoluminescence emission spectrum of Cu₂CoSnS₄ at λ_exc = 270 nm.

We extended our success of synthesizing quaternary phases, to generate novel compositions consisting of other p-block elements. PXRD pattern from the reaction of thiourea complexes of copper, tin and bismuth is shown in Fig. 5a. Using auto indexing program TREOR, all the observed reflections could be indexed in an orthorhombic symmetry with a = 6.833 (12) Å, b = 8.153 (15) Å and c = 38.889 (89) Å. The observed parameters were slightly higher than the values of Cu₃SnS₄ hinting possible substitution of larger Bi³⁺-ion (0.103 nm) for some of the relatively smaller Sn⁴⁺-ions (0.055 nm). Flower like morphology was noticed for the samples in its SEM images (Fig. S11 ESI†). EDX analysis, performed at various locations of the sample, indicated the uniform presence of bismuth in the samples in addition to copper, tin and sulfur. From the analysis, the obtained ratio of Cu : Bi : Sn : S was 2.9 : 0.4 : 1.0 : 3.7. Elemental mapping also confirmed the homogeneous distribution of the elements in the samples (Fig. 5b). In the Raman spectrum of Bi³⁺ substituted Cu₃SnS₄, three bands at 290, 316 and 347 cm⁻¹ were observed as against four for Cu₃SnS₄. The absence of most intense band at 333 cm⁻¹, a typical feature noticed in Cu₃SnS₄, suggested the change in the vibration mode of Sn–S by the substitution of bismuth (Fig. 6a). Broad absorbance over the entire range of visible region with band edge near 950 nm was observed in the UV-vis-NIR spectrum of Bi³⁺-substituted sample (Fig. 6b). Band gap from the Tauc plot was 1.21 eV (Fig. 6c). Emission maxima shifted from 342 nm (for Cu₃SnS₄) to 315 nm (for Bi-substituted sample) and this could possibly due to ³P_0,1 → ¹S₀ transition of Bi³⁺-ion (Fig. 6d).²⁷

Fig. 5 (a) PXRD pattern and (b) scanning SEM image of the sample obtained from the reaction to include Bi³⁺ in Cu₃SnS₄.

Fig. 6 (a) Raman spectrum (b) UV-vis-NIR absorption (c) band gap estimation plot and (d) photoluminescence emission spectrum of the sample obtained from the reaction to include Bi³⁺ in Cu₃SnS₄ at λ_exc = 270 nm.

Fig. 7a shows the PXRD pattern of the product resulted from our attempts to include Sb³⁺ in Cu₃SnS₄ lattice. The diffraction pattern resembled closely with the one for Cu₂CoSnS₄. The pattern could very well be indexed in tetragonal symmetry (I4̄2m space group) with lattice constants, a = 5.395 (95) Å and c = 11.429 (24) Å. To appreciate the finer distinctions between the synthesized compositions, the indexed parameters used for their PXRD patterns, the band gap values, Raman band positions and the emission band positions in the PL spectra have been compiled in Tables 1 and 2, respectively. Flower like morphology was seen uniformly throughout the scanned area in the SEM images of the Sb³⁺ containing sample. EDX analysis at various locations yielded ratio of 3.1 : 0.3 : 0.9 : 3.7 for Cu : Sb : Sn : S (Fig. S11 ESI†). Also, elemental mapping by SEM-EDX analysis confirmed the homogeneous distribution of constituent elements of the sample (Fig. 7b). Raman spectrum of this sample is shown in Fig. 8a. Three bands centered at 282, 314 and 348 cm⁻¹ could be located after deconvolution (Fig. 8a). Observed bands were anti-stoke shifted from the positions observed for Cu₂CoSnS₄. Band gap of 0.99 eV was estimated from UV-vis-NIR spectral data (Fig. 8b and c). When excited with 270 nm, emission at 342 nm was observed. Observed emission could be assigned to the transition of spin forbidden relaxation ³P₁–¹S₀ of Sb³⁺-ion (ns² type) (Fig. 8d).²⁸

Fig. 7 (a) PXRD pattern and (b) scanning SEM image of the sample from the reaction to include Sb³⁺ in Cu₃SnS₄.

Table 1 Crystallographic data of orthorhombic Cu₃SnS₄, Cu₂NiSnS₄, Cu₂BiSnS₄, Cu₂CoSnS₄ and Cu₂SbSnS₄

Formula	Cu3SnS4	Cu2NiSnS4	Cu2BiSnS4	Cu2CoSnS4	Cu2SbSnS4
Crystal system	Orthorhombic	Orthorhombic	Orthorhombic	Tetragonal	Tetragonal
Space group	Pmn21	Pmn21	Pmn21	I4̄2m	I4̄2m
a [Å]	6.787 (44)	6.581 (18)	6.833 (12)	5.471 (13)	5.395 (95)
b [Å]	7.728 (78)	8.104 (31)	8.153 (15)	5.471 (13)	5.395 (95)
c [Å]	37.555 (33)	37.754 (95)	38.889 (89)	11.663 (51)	11.429 (24)
V [Å^3]	1970.09 (29)	2045.50 (11)	2166.76 (75)	349.10 (23)	332.76 (14)
Rexp (%)	0.77	1.54	1.73	1.15	3.13
Rp (%)	0.75	1.41	1.56	1.21	2.90
Rwp (%)	1.00	1.78	1.99	1.62	3.70
GoF	1.30	1.15	1.15	1.41	1.18
Step size time per step	0.01313°	0.01313°	0.01313°	0.01313°	0.01313°
Temperature	298 K	298 K	298 K	298 K	298 K

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Table 2 Summary of Raman, UV-vis-NIR and photoluminescence spectral details of the compounds under the present study

S. no.	Composition	Raman band positions (cm^−1)	Band gap from UV-vis-NIR data (eV)	PL emission band positions (nm)
1	Cu3SnS4	282, 317, 333, 346	1.21	417, 439
2	Cu2NiSnS4	282, 311, 348	1.46	342
3	Cu2CoSnS4	288, 320, 347	1.23	330
4	Cu2(Bi/Sn)S4	290, 316, 347	1.21	315
5	Cu2(Sb/Sn)S4	282, 314, 348	0.99	342

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Fig. 8 (a) Raman spectrum (b) UV-vis-NIR absorption (c) band gap estimation plot and (d) photoluminescence emission spectrum of the sample from the reaction to include Sb³⁺ in Cu₃SnS₄.

4. Conclusions

A simple, reliable, rapid and low-cost synthetic method has been developed for the photovoltaic material, Cu₃SnS₄ in orthorhombic symmetry. The structure, symmetry and homogenous distribution of the constituents have been verified from diffraction, spectroscopy and microscopy techniques. Optical band gap of Cu₃SnS₄, estimated from the UV-vis-NIR spectroscopy data, was 1.21 eV. Substituting Cu₃SnS₄ with d-block ions (Ni²⁺, Co²⁺) and p-block ions (Bi³⁺, Sb³⁺) resulted in either variation in the symmetry and/or the optical band gap values in the range, ideally suited for photovoltaic applications. The philosophy of these sets of reactions has the potential to generate new compositions in other ternary and quaternary compositions.

Acknowledgements

Authors wish to record their sincere thanks to DST (Nanomission) and DST (SB/S1/PC-08/2012) for funding this research. MG and PR thanks CSIR, New Delhi and DST respectively for their fellowship. Thanks are due to University of Delhi, Delhi for the usage of facilities of CIF, M.Tech (NSNT) program.

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Footnote

† Electronic supplementary information (ESI) available: FTIR and Raman spectrum of precursors, SEM-EDX of Cu₃SnS₄, SEM image, EDX spectrum, SAED pattern and elemental mapping of Cu₂NiSnS₄, SEM-EDX of Cu₃SnS₄, nickel, cobalt, bismuth and antimony substituted Cu₃SnS₄. See DOI: 10.1039/c4ra17125j

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