Two novel heptanuclear 3d-4f helicates have been synthesized and characterized. The helicates act as catalysts and show high catalytic activity for the coupling of CO and epoxides to obtain cyclic carbonates with a wide substrate scope at ambient temperature and pressure.

Mimicking nature seems to be one of the smartest strategies to design novel catalysts for CO2 conversion under mild conditions.

Two series of anion-induced 3d-4f luminescent clusters ZnII2LnIII2L4 (LnIII = Eu3+, Tb3+, Er3+, Yb3+, Nd3+) and ZnII4LnIII2L4 (LnIII = Tb3+, Nd3+) based on μ3-OH group were synthesized and characterized. The difference in anions not only leads to significant structural changes, but also changes the luminescent properties of the 3d-4f coordination clusters. These complexes show excellent catalytic performance for CO2 conversion to obtain cyclic carbonates with wide substrate scopes and high selectivity under mild conditions. Turnover numbers were up to 9000, and turnover frequencies obtained were 660 h-1. The ligand is simple and the complexes are easily obtained even on a large scale. Moreover, these complexes also feature lanthanide-characterized luminescence both in visible and near infrared regions with relatively long luminescence lifetimes and high quantum yields, suggesting promising multifunctional applications.

A series of 4-nuclear lanthanide clusters supported by organic ligands Zn3LnL4 (Ln = Dy(1), Gd(2), Er(3)) were synthesized. These helicates could be used to convert CO2 into cyclic carbonates with TOF up to 38 000 h−1, without being influenced by moisture or air.

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A series of hexanuclear 3d–4f complexes with unique structures as catalysts for CO2 fixation into cyclic carbonates under mild conditions.

Ultrathin two-dimensional (2D) metal–organic framework (MOF) nanosheet membranes have shown significant promise for gas separation application because of their excellent molecular transport characteristics. However, the preparation of oriented 2D MOF membranes by direct growth remains challenging, especially on tubular substrates. In this study, we propose a bottom-up strategy to prepare a highly oriented 2D Co2(bIm)4 (bIm = benzimidazole) membrane via the conversion of Co­(OH)2 sheets with assistance from graphene oxide (GO) in organic ligand synthetic solution. Both the introduced GO and Co­(OH)2 layers play important roles in inducing the highly oriented growth of stable 2D Co2(bIm)4 membranes. The obtained 2D Co2(bIm)4 membrane of around 210 nm in thickness displays outstanding separation properties. The permeance for H2 is 2.54 × 10–7 mol·m–2·s–1·Pa–1, and the ideal selectivities for H2/CO2, H2/N2, and H2/CH4 are as high as 23.1, 18.5, and 28.7, respectively. This approach opens up a new avenue via a direct growth method for preparing highly oriented MOF nanosheet tubular membranes for efficient gas separation.