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.

Late-onset epilepsy (LOE), with onset after 50 years of age, is often attributed to underlying occult cerebrovascular disease. LOE is associated with a three-fold increase in subsequent stroke risk, therefore it is important to improve our understanding of pathophysiology. In this exploratory study, we aimed to determine whether established structural magnetic resonance imaging markers and novel physiological imaging markers of occult cerebrovascular disease were more common in patients with LOE than age-matched controls.Sixteen patients with LOE (mean age ± SD: 67.6 ± 6.5 years) and 15 age-matched control subjects (mean age: 65.1 ± 3.9 years) underwent a 3 T MRI scan protocol. T1-weighted images and T2-weighted fluid attenuated inversion recovery (FLAIR) images were used to determine cortical grey matter volume and white matter hyperintensity (WMH) volume respectively, whilst multiple delay time arterial spin labelling (ASL) images were collected at rest and during a hypercapnic challenge. Cerebral blood flow (CBF) and arterial arrival time (AAT) were calculated from ASL data under both normocapnic and hypercapnic conditions. Cerebrovascular reactivity was also calculated for both CBF and AAT relative to the change in end-tidal CO2.Patients with LOE were found to have significantly lower cortical volume than control subjects (33.8 ± 3.8% of intracranial volume vs. 38.0 ± 5.5%, p = 0.02) and significantly higher WMH volume (1339 ± 1408 mm3 vs. 514 ± 481 mm3, p = 0.047). Baseline whole brain AAT was found to be significantly prolonged in patients with LOE in comparison to control subjects (1539 ± 129 ms vs. 1363 ± 167 ms, p = 0.005). Voxel-based analysis showed the significant prolongation of AAT to be predominantly distributed in the frontal and temporal lobes. Voxel-based morphometry showed the lower cortical volume to be localised primarily to temporal lobes. No significant differences in CBF or cerebrovascular reactivity were found between the two groups. Baseline whole brain AAT and cortical volume differences persisted upon further analysis to take account of differences in smoking history between patients and control subjects.These findings suggest that occult cerebrovascular disease is relevant to the pathophysiology of LOE.

The antimony-iron sulfide system in general does not produce alloys below 540 °C from traditional solid-state methods. However, single source precursors have been known to produce unexpected products that arise from kinetically trapped polymorphs. In this paper, we test the efficacy of this approach toward the Fe-Sb-S system. Antimony and iron diethyldithiocarbamate complexes of the form Sb[S2CN(Et2)]3 (1) and Fe[S2CN(Et2)]3 (2) were synthesised, characterised, and used as single-source precursors for the preparation of Sb2S3, FexSy, and mixed iron antimony sulfide Sb2(1−x)Fe2xS3 (0 ≥ x ≥ 1) powders using the solvent-less thermolysis method at different temperatures ranging from 300 to 475 °C. The effect of different mole fractions of the iron precursor was evaluated on morphology, shape, and optical and magnetic properties of Sb2(1−x)Fe2xS3 (0 ≥ x ≥ 1). The obtained powders were characterized by X-ray diffraction (XRD), Raman spectroscopy scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, magnetometer measurement, and UV/vis/NIR spectroscopy. The results demonstrated that the crystalline structure, morphology, and elemental composition of the samples changed with the mole fraction of the precursor. There was significant phase separation between Sb and Fe sulfides noted from EDX spectroscopic mapping, yet an optoelectronic study monitoring the direct band gap energy of antimony sulfide shows that the band gap energy increases as a function of Fe content, which suggests limited alloying is possible from the single source route.

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