Steering perovskite precursor solutions for multijunction photovoltaics.

Multijunction photovoltaics (PVs) are gaining prominence owing to their superior capability of achieving power conversion efficiencies (PCEs) beyond the radiative limit of single-junction cells, where improving narrow bandgap tin-lead perovskites is critical for thin-film devices. With a focus on understanding the chemistry of tin-lead perovskite precursor solutions, we herein find that Sn(II) species dominate interactions with precursors and additives and uncover the exclusive role of carboxylic acid in regulating solution colloidal properties and film crystallisation, and ammonium in improving film optoelectronic properties. Materials that combine these two function groups, amino acid salts, considerably improve the semiconducting quality and homogeneity of perovskite films, surpassing the effect of the individual functional groups when introduced as part of separate molecules.

Circularly polarized luminescence induction on a Tb(III) complex with a tris(-butylaryloxide)-functionalized 1,4,7-triazacyclononane ligand coordinating chiral 1-phenylethylamine.

Circularly polarized luminescence (CPL) activity was induced on a racemic Tb complex with a 1,4,7-triazacyclononane-based tris-phenoxide ligand by the coordination of a chiral 1-phenylethylamine ligand to the Tb centre. -Butyl groups at the -position of the phenoxide moieties were found to be important for efficient CPL induction in the Tb complex.

Single-gold etching at the hypercarbon atom of C-centred hexagold(I) clusters protected by chiral N-heterocyclic carbenes.

Chemical etching of nano-sized metal clusters at the atomic level has a high potential for creating metal number-specific structures and functions that are difficult to achieve with bottom-up synthesis methods. In particular, precisely etching metal atoms one by one from nonmetallic element-centred metal clusters and elucidating the relationship between their well-defined structures, and chemical and physical properties will facilitate future materials design for metal clusters. Here we report the single-gold etching at a hypercarbon centre in gold(I) clusters.

'Passivated Precursor' Approach to All-Alkynyl-Protected Gold Nanoclusters and Total Structure Determination of Au.

A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all-alkynyl-protected gold nanoclusters. Direct reduction of dpa-passivated precursor Au-dpa (Hdpa=2,2'-dipyridylamine) in one-pot under ambient conditions gives a series of clusters including Au(C≡CR) (R=-CH-2-F), Au(C≡CR), Au(C≡CR), Au(C≡CR), and Au(C≡CR). These clusters can be well separated via column chromatography.