Silver bismuth iodides are non-toxic and comparatively cheap photovoltaic materials, but their wide bandgaps and downshifted valence band edges limit their This article is protected by copyright. All rights reserved. performance as light absorbers in solar cells. Herein, we introduce a strategy to tune the optoelectronic properties of silver bismuth iodides by partial anionic substitution with the sulfide dianion. A consistent narrowing of the bandgap by 0.1 eV and an upshift of the valence band edge by 0.1-0.3 eV upon modification with sulfide are demonstrated for AgBiI 4 , Ag 2 BiI 5 , Ag 3 BiI 6 and AgBi 2 I 7 compositions. Solar cells based on silver bismuth sulfoiodides embedded into a mesoporous TiO 2 electron transporting scaffold, and a poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] hole transporting layer significantly outperform devices based on sulfide-free materials, mainly due to enhancements in the photocurrent by up to 48 %. A power conversion efficiency of 5.44 ± 0.07 % (J sc = 14.6 ± 0.1 mA cm -2 ; V oc = 569 ± 3 mV; fill factor = 65.7 ± 0.3 %) under 1 sun irradiation and stability under ambient conditions for over a month are demonstrated. The results reported herein indicate that further improvements should be possible with this new class of photovoltaic materials upon advances in the synthesis procedures and an increase in the level of sulfide anionic substitution.

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Many first-line treatments for neglected tropical diseases identified by the World Health Organization (WHO) are limited by one or more of the following: the development of drug resistance, toxicity, and side effects, lack of selectivity, narrow therapeutic indices, route of administration, and bioavailability. As such, there is an urgent need to develop viable alternatives to overcome these limitations. The following review provides an overview of all existing metal complexes studied and evaluates the status of these complexes on the respective disease of choice.

Two synthetic approaches to the formation of bismuth(III) carboxylates have been explored and compared. Ph(3)Bi was reacted with a series of carboxylic acids (RCO(2)H) of varying pK(a) and functionality (R = PhCH[double bond, length as m-dash]CH, o-MeOC(6)H(4), m-MeOC(6)H(4), o-H(2)NC(6)H, o-O(2)NC(6)H(4), p-O(2)NC(6)H(4), 2-(C(5)H(4)N)) under reflux conditions in toluene and solvent-free. The thermochemical profiles of the solvent-free reactions were also studied by DSC-TGA. All reactions produced the tri-substituted bismuth carboxylates in comparable yields and purity with the exceptions of picolinic acid and p-nitrobenzoic acid. 2-Picolinic acid exclusively formed the di-substituted complex, [PhBi(2-(C(5)H(4)N)CO(2))(2)](4), by both methods, while p-nitrobenzoic acid gave the tri-substituted complex through reflux and the di-substituted complex under solvent-free conditions. Two of the complexes were structurally authenticated by single crystal X-ray diffraction: [PhBi(2-(C(5)H(4)N)CO(2))(2)](4) is tetrameric formed through five membered chelate rings involving the pyridyl N and O(-C) rather than the less stable carboxylate (-CO(2)) chelates, while [Bi(o-MeOC(6)H(4)CO(2))(3)](infinity), is a polymer in which dimeric units, constructed around two chelating and one unsymmetrical bridging carboxylate on each Bi centre, are then joined together through longer intermolecular Bi-O bridging bonds.

Bismuth-based compounds have been used extensively as medicines for the treatment of gastrointestinal disorders and H. pylori infections. Bismuth compounds and Bi-based nanomaterials show promise for emerging infectious diseases, cancer (e.g.213Bi) and also imaging.