Recent progress of MOF-based photoluminescent platforms: a comprehensive overview of their applications in biosensing and underlying mechanisms.

We show that the low frequency, long wavelength dynamics of the phase of the pair field for a BCS-type s-wave superconductor at T=0 is equivalent to that of a time-dependent non-linear Schrödinger Lagrangian (TDNLSL), when terms required by Galilean invariance are included. If the modulus of the pair field is also allowed to vary, the system is equivalent to two coupled TDNLSL's. 67.50.Fi

Covalent organic frameworks (COFs) are distinguished from other organic polymers by their crystallinity1–3, but it remains challenging to obtain robust, highly crystalline COFs because the framework-forming reactions are poorly reversible4,5. More reversible chemistry can improve crystallinity6–9, but this typically yields COFs with poor physicochemical stability and limited application scope5. Here we report a general and scalable protocol to prepare robust, highly crystalline imine COFs, based on an unexpected framework reconstruction. In contrast to standard approaches in which monomers are initially randomly aligned, our method involves the pre-organization of monomers using a reversible and removable covalent tether, followed by confined polymerization. This reconstruction route produces reconstructed COFs with greatly enhanced crystallinity and much higher porosity by means of a simple vacuum-free synthetic procedure. The increased crystallinity in the reconstructed COFs improves charge carrier transport, leading to sacrificial photocatalytic hydrogen evolution rates of up to 27.98 mmol h−1 g−1. This nanoconfinement-assisted reconstruction strategy is a step towards programming function in organic materials through atomistic structural control.

Using interfacial force microscopy and a spherical glass probe, we investigate the adhesive and mechanical properties of the so-called liquid-like layer (L-LL) on the surface of ice at various temperatures over the range from -10 to -30 degrees C. We find that the layer thickness closely follows that predicted on thermodynamic grounds, while the adhesive interaction has the behavior of a "frustrated capillary", strongly suggesting that the layer is viscoelastic. This viscoelasticity is directly probed using a lateral-dither technique to obtain information on the layer's viscous response as a function of both temperature and interfacial separation.

Metal–organic cages are potential artificial models for mimicking biological functions due to their capability of selective encapsulation for certain guest molecules. In this work, we designed and synthesized a series of rhombic dodecahedral Ni-imidazolate cages (Ni14L24) with precisely controlled aperture for CO2 encapsulation. The aperture of the cages can be tuned by the strategies of ligand decoration and metal-ion hybridization. Similar to the breathing function of alveoli, CO2 passes through the dynamic aperture into the cages under a pressure of 2.0–3.0 bar in methanol solution, and slowly move out of the cages when the pressure goes down. In the solid state, CO2 is encapsulated and prisoned in the cages under a high pressure of 15.0–30.0 bar or supercritical conditions. By replacing the square-coordinated Ni2+ with Cu2+, the resulting Ni–Cu heteronuclear cage lost the capability of physically encapsulating CO2 even though the aperture’s size is only slightly changed.

A strategy to improve the framework porosity and hydrophobicity of the pore surface by doping metal ions (Cu(2+), Cd(2+), or Fe(2+)) into a gyroidal MOF STU-1 has been developed. It is found that the obtained heterometallic MOFs are exceptionally water stable.

Cu3(4-chloropyrazolate)3 is presented herein to exhibit unprecedented room-temperature white phosphorescence by modulating monomeric blue and excimeric yellow phosphorescence.

We describe silver clusters which unexpectedly transform from cyclic trinuclear complexes and σ-donating phenylacetylene, featuring a noria-like conformation. The introduction of Cu ions leads to isomorphic clusters which boost emission efficiency.