Synthesis of ternary copper antimony sulfide via solventless thermolysis or aerosol assisted chemical vapour deposition using metal dithiocarbamates

Abstract

Copper antimony sulfide (Cu-Sb-S) has recently been proposed as an attractive alternative photovoltaic material due to the earth-abundant and non-toxic nature of the elements, high absorption coefficients and band gaps commensurate with efficient harvesting of solar photonic flux across multiple phases of Cu-Sb-S. These materials are therefore highly desirable and sustainable and scalable deposition techniques to produce them are of interest. In this paper, we demonstrate two facile, low-temperature and inexpensive techniques (solventless thermolysis and aerosol-assisted chemical vapor deposition (AACVD)) for the preparation of binary digenite (Cu1.8S), chalcocite (Cu2S) and stibnite (Sb2S3) and several phases of ternary copper-antimony-sulfide (Cu2xSb2(1−x)Sy, where 0 ≤ x ≤ 1). It was found that by utilising these different techniques and varying the ratio of Cu:Sb, pure phases of ternary chalcostibite (CuSbS2), fematinite (Cu3SbS4) and tetrahedrite (Cu12Sb4S13) can be achieved. Two single-source precursors were investigated for this purpose, namely the diethyldithiocarbamate (DTC) complexes of copper and antimony Cu(DTC)2 and Sb(DTC)3. These were decomposed both individually (to produce binary materials) and combined (to produce ternary materials) at different ratios. From the solventless thermolysis and AACVD methods, either particulate or thin film material was formed, respectively. These materials were then characterised by powder XRD, SEM, EDX and Raman spectroscopies to determine the crystalline phase, material morphology and uniformity of elemental composition. This analysis demonstrated that as the Cu-content increases, the phase of the ternary material changes from chalcostibite (CuSbS2) and fematinite (Cu3SbS4) at a low Cu:Sb ratio to tetrahedrite (Cu12Sb4S13) at a high Cu:Sb ratio.

A facile synthetic route toward phase-pure colloidal Cu2GeS3 nanostructures mediated through metal xanthate precursors

“…Lewis's research group has extensively explored the versatility of metal xanthates and thiocarbamates for the phase-pure preparation of various exotic multinary metal sulfides. [14][15][16][17] Similarly, Revaprasadu et al have also investigated the suitability of xanthates and thiocarbamates for the preparation of several important nanosized metal sulfides. [18][19][20] However, a thorough literature study has revealed that xanthates have not been explored for the preparation of technologically important Cu 2 GeS 3 nanocrystals.…”

Molecular precursor-mediated facile synthesis of photo-responsive stibnite Sb2S3 nanorods and tetrahedrite Cu12Sb4S13 nanocrystals

“…It is important to note here that there are several reports in the literature, wherein despite the mismatch between the calculated and observed weight loss in TG, the complex serves as an efficient precursor for the synthesis of nanostructures by either solventless or solvent mediated routes. 26,32,36,44…”

“…31 Alternatively, reports suggest that high-purity Cu 12 Sb 4 S 13 (tetrahedrite) can easily be produced using a molecular precursor route. 15,32,33 and studied its photo-induced charge transfer characteristics. 10 In another experiment, diethylcarbamates of copper and antimony were successfully used for the solvothermal preparation of high-purity Cu 12 Sb 4 S 13 with multiply-voided morphology.…”

“…10 In another experiment, diethylcarbamates of copper and antimony were successfully used for the solvothermal preparation of high-purity Cu 12 Sb 4 S 13 with multiply-voided morphology. 33 However, to date, only a handful of molecular precursors derived from xanthates, 10,15,28 dithiocarbamates [32][33][34] and thiobenzoates 28,29 have been used for the preparation of Sb 2 S 3 and CAS.…”

“…31 Alternatively, reports suggest that high-purity Cu 12 Sb 4 S 13 (tetrahedrite) can easily be produced using a molecular precursor route. 15,32,33 For instance, Lewis and co-workers have used both xanthates and dithiocarbamates of Cu and Sb to obtain Cu 12 Sb 4 S 13 . 15,30 Similarly, Rath et al have used xanthates to produce Cu 12 Sb 4 S 13 and studied its photo-induced charge transfer characteristics.…”