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An effective strategy is developed to synthesize high-nuclearity Cu clusters, [Cu 53 (RCOO) 10 (C≡CtBu) 20 Cl 2 H 18 ] + (Cu 53 ), which is the largest Cu I /Cu 0 cluster reported to date. Cu powder and Ph 2 SiH 2 are employed as the reducing agents in the synthesis. As revealed by single-crystal diffraction, Cu 53 is arranged as a four-concentric-shell Cu 3 @Cu 10 Cl 2 @Cu 20 @Cu 20 structure, possessing an atomic arrangement of concentric M 12 icosahedral and M 20 dodecahedral shells which popularly occurs in Au/Ag nanoclusters. Surprisingly, Cu 53 can be dissolved in diethyl ether and spin coated to form uniform nanoclusters film on organolead halide perovskite. The cluster film can subsequently be converted into high-quality CuI film via in situ iodination at room temperature. The as-fabricated CuI film is an excellent hole-transport layer for fabricating highly stable CuI-based perovskite solar cells (PSCs) with 14.3 % of efficiency., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A general method, using mixed ligands (here diphosphines and thiolates) is devised to turn an achiral metal cluster, Au 13 Cu 2 , into an enantiomeric pair by breaking (lowering) the overall molecular symmetry with the ligands. Using an achiral diphosphine, a racemic [Au 13 Cu 2 (DPPP) 3 (SPy) 6 ] + was prepared which crystallizes in centrosymmetric space groups. Using chiral diphosphines, enantioselective synthesis of an optically pure, enantiomeric pair of [Au 13 Cu 2 ((2r,4r)/(2s,4s)-BDPP) 3 (SPy) 6 ] + was achieved in one pot. Their circular dichroism (CD) spectra give perfect mirror images in the range of 250-500 nm with maximum anisotropy factors of 1.2×10 -3 . DFT calculations provided good correlations with the observed CD spectra of the enantiomers and, more importantly, revealed the origin of the chirality. Racemization studies show high stability (no racemization at 70 °C) of these chiral nanoclusters, which hold great promise in applications such as asymmetry catalysis., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

By using ethylene glycol and monocarboxylic acid as surface ligands, a series of cyclic Ti-oxo clusters (CTOC) with permanent microporosity are successfully synthesized. With a cyclic {Ti 32 O 16 } backbone made of eight connected Ti 4 tetrahedral cages that are arranged in a zigzag fashion, the clusters have a "donut" shape with an inner diameter of 8.3 Å, outer diameter of 26.9 Å and height of 10.4 Å. While both inner and outer walls of the "donut" clusters are modified by double-deprotonated ethylene glycolates, their upper and lower surfaces are bound by carboxylates and mono-deprotonated ethylene glycolates. The clusters are readily packed into one-dimensional tubes which are further arranged in two different modes into crystalline microporous solids with surface areas over 660 m 2  g -1 , depending on the surface carboxylates. The solid with olefin-bearing carboxylates exhibits a superior CO 2 adsorption capacity of 40 cm 3  g -1 at 273 K under 1 atm. Moreover, the mono-deprotonated ethylene glycolates on the clusters are demonstrated to be highly exchangeable by other alcohols, providing a nice platform for creating microporous solids or films with a wide variety of surface functionalities., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)