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The study of Bi2Rh formation in a polyol process revealed a two-step mechanism. BiRh is formed by co-reduction of bismuth and rhodium cations and converted into Bi2Rh by Bi diffusion. Various starting materials and reaction parameters are examined.

Intermetallic phases are usually obtained by crystallization from the melt. However, phases containing elements with widely different melting and boiling points, as well as nanoparticles, which provide a high specific surface area, are hardly accessible via such a high-temperature process. The polyol process is one option to circumvent these obstacles by using a solution-based approach at moderate temperatures. In this study, the formation of Bi2Ir nanoparticles in a microwave-assisted polyol process was investigated. Solutions were analyzed using UV–Vis spectroscopy and the reaction was tracked with synchrotron-based in situ powder X-ray diffraction (PXRD). The products were characterized by PXRD and high-resolution transmission electron microscopy. Starting from Bi(NO3)3 and Ir(OAc)3, the new suboxide Bi4Ir2O forms as an intermediate phase at about 160 °C. Its structure was determined by a combination of PXRD and quantum-chemical calculations. Bi4Ir2O decomposes in vacuum at about 250 °C and is reduced to Bi2Ir by hydrogen at 150 °C. At about 240 °C, the polyol process leads to the immediate reduction of the two metal-containing precursors and crystallization of Bi2Ir nanoparticles.

Ionic liquids (ILs) are widely used as versatile solvents for the synthesis of nanomaterials. However, the effect of IL impurities on the formation of nanomaterials is often neglected. Herein, we report on the formation of tellurium (Te) nanoparticles from the reaction of trialkylphosphane tellurides, formed by reactive dissolution of Te in dried commercial trihexyltetradecylphosphonium chloride ([P66614]Cl) at high temperatures, with common polar protic solvents (e.g. water, alcohols, or amides). Highly homogeneous Te nano- and microstructures with various sizes and morphologies including three-dimensional (3D) Te fusiform assemblies and 3D aloe-like Te microarchitectures are obtained. Our investigation shows that trace amounts of HCl impurities in [P66614]Cl tend to remain as [P66614][HCl2] due to the strong interaction with Cl−. The addition of a polar, protic solvent liberates active HCl from the HCl2− anion which we found to play an essential role in the formation of Te particles due to the accelerating effect of P–Te bond cleavage. This approach presents a general and convenient synthetic strategy for the preparation of Te nano- and microstructures.

A new coordination polymer [Hg(LI)I]n (1) and a new discrete coordination complex [Hg(HLII)I2] (2) are synthesized and X-ray characterized. The existence of positive π-holes at the spodium atoms in both compounds is evidenced by DFT calculations. In 1, a Hg-S semicoordination bond and a HgI spodium bond are formed at opposite sides of the π-hole. In 2, two different HgI spodium bonds are formed at both sides of the π-hole. This is the first study describing structure-guiding π-hole spodium bonding.

Correction for ‘On the importance of π-hole spodium bonding in tricoordinated HgII complexes’ by Ghodrat Mahmoudi et al., Dalton Trans., 2020, 49, 17547–17551, https://doi.org/10.1039/D0DT03938A.

The mechanism of the synthesis of copper(I) phosphide (Cu3−xP) in the ionic liquid (IL) trihexyl(tetradecyl)phosphonium chloride ([P66614][Cl]) was investigated. The phosphide formation is promoted by a transformation of red phosphorus (Pred) into mobile P4 molecules and a surface activation of copper caused by the IL including the Bronsted acidic impurity. The surface activation is important to obtain a quantitative product yield. Moreover, we demonstrate that single-phase Cu3−xP can also be synthesized in the nitrogen-based IL tetrabutylammonium chloride ([N4444][Cl]). Further substitution of the anion of the IL using tetrabutylammonium bromide ([N4444][Br]) or the complete replacement of the IL by a deep eutectic solvent consisting of adipic acid and betaine do not lead to single-phase Cu3−xP. Therefore, the nature of the anions present in the IL also seems to be relevant for the convenient phosphidization reaction.