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We report a facile and low temperature synthesis of Ga- and In-doped CdS nanoparticles from molecular precursors. Diethyldithiocarbamate complexes of Cd(ii), Ga(iii), and In(iii), were synthesised and decomposed in tandem through solventless thermolysis, producing Ga- or In-doped CdS. The resultant M xCd 1−xS 1+0.5x (where M = Ga/In at x values of 0, 0.02, 0.04, 0.06, 0.08 and 0.1) particulate powder was analysed by powder X-ray diffraction, which showed that both Ga (through all doping levels) and In (at doping levels xCd 1−xS 1+0.5x materials were examined by UV-Vis absorption and photoluminescence spectroscopies respectively. All materials were found to exhibit excitonic emission, corresponding to band gap energies between 2.7 and 2.9 eV and surface defect induced emission which is more prominent for Ga than for In doping. Additionally, moderate doping slows down charge carrier recombination by increasing the lifetimes of excitonic and surface state emissions, but particularly for the latter process.

Glucosinolates (Gls) are natural bioactive compounds that form metabolites called isothiocyanates (ITC) which have various therapeutic effects. This study aimed to isolate the glucosinolates of Carrichtera annua L.(DC) (CA) and Farsetia aegyptia Turra (FA) belonging to the Crucifereae family. Total Gls were isolated from the aqueous methanolic extract of the plants and further purified using an acidic aluminum oxide column. Some of the obtained Gls were identified via spectroscopic methods (UV, NMR, and MS) and the rest were hydrolyzed by myrosinase to the corresponding isothiocyanates (ITC) for identification by GC/MS. Only one Gls was identified in CA as 4-methylthio-3-butenyl Gls (MTBG) in addition to 6-methyl sulfonylhexyl isothiocyanates (ITC), while 6-methyl sulfonyl-6-hydroxy hexyl ITC, 4-pentenyl ITC, 3-methylthio propyl ITC, 5-hydroxy pentyl ITC and 4-methylsulphinyl butyl ITC were identified in FA. The Gls demonstrated high binding activity to α-glucosidase and amylase, good pharmacokinetic characteristics, and exerted no carcinogenetic effects.

Alkyl-xanthato gallium(III) complexes of the form [Ga(S2COR)3] where R= Me (1), Et (2), iPr (3), nPr (4), nBu (5), sBu (6) and iBu (7) have been synthesized and fully characterised. Crystal structures for 1 and 3-7 have been solved and their structures examined to elucidate if their structure is related to their decomposition. Thermogravimetric analysis was used to give insight into the decompostion temperatures for every complex. Unlike previously explored metal xanthate complexes which break down at low temperatures (< 250 °C), to form crystalline metal chalcogenides, powder X-ray diffraction measurements suggest that when R ≥ Et thesecomplexes did not produce crystalline gallium sulfide until heated to 500 °C, where the γ-Ga2S3 was the sole product formed. In the case of R = Me Chugeav elimination is unable to occur and amphorphous GaxSy products were formed. We conclude therefore that the low temperature synthesis route offered by the thermal decompsoition of metal xanthate precursors, which has been reported for many metal sulfide systems prior to this, may not be appropriate in the case of gallium sulfides.

A range of binary, ternary (CFS), and quaternary (CZTS) metal sulfide materials have been successfully deposited onto the glass substrates by air-spray deposition of metal diethyldithiocarbamate molecular precursors followed by pyrolysis (18 examples). The as-deposited materials were characterized by powder X-ray diffraction (p-XRD), Raman spectroscopy, secondary electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy, which in all cases showed that the materials were polycrystalline with the expected elemental stoichiometry. In the case of the higher sulfides, EDX spectroscopy mapping demonstrated the spatial homogeneity of the elemental distributions at the microscale. By using this simple and inexpensive method, we could potentially fabricate thin films of any given main group or transition metal chalcogenide material over large areas, theoretically on substrates with complex topologies.

Alkyl-xanthato gallium(iii) complexes of the form [Ga(S