Sandwich-Like Encapsulation of a Highly Luminescent Copper(I) Complex

A small molecular weight cationic copper(I) complex showing high luminescence quantum yield based on a thermally activated delayed fluorescence mechanism is immobilized between two 1 nm thin silicate layers. Partial ion exchange of the emitter into a synthetic layered silicate (fluorohectorite) yields an ordered heterostructure with two types of strictly alternating interlayers: a monolayer of the cationic emitter and a monolayer of hydrated Na+ cations. Osmotic swelling of the latter produces dispersions of double-stacks in which the emitter monolayer is encapsulated between two silicate layers. The electrostatic attraction of the emitter interlayer with the oppositely charged silicate layers exerts electrostatic pressure on the emitter. Compared to crystalline salt, rigid confinement for the encapsulated emitter provides improved thermal stability and increased emission quantum yield at ambient temperature. The suspension of delaminated, micrometer-sized double-stacks of 3.9 nm thickness allows for easy solution processing of low-cost optoelectronic devices, such as light-emitting electrochemical cells and organic light-emitting diodes

Multi-Mixed Metal Hydroxide as a Strong Stratigraphic Nanoclay Inhibitor in Solid-Free Drilling Fluid

Solid-free drilling fluid has more advantages as a new type of drilling fluid compared with traditional drilling fluid, such as improving drilling efficiency, protecting oil and not having clay particles clog the oil and gas layer. In this study, Zn/Cu/Fe-doped magnesium–aluminum hydroxide (Mg-Al MMH) was prepared using the co-precipitation method and evaluated in solid-free drilling fluid. The inhibition mechanism of synthesized hydroxide was analyzed by X-ray diffraction, laser particle-size analysis and thermogravimetric analysis. The samples were directly used as drilling fluid base muds for performance evaluation. The results showed that the linear expansion rate of 4% M6-Fe was only 12.32% at room temperature within 2 h, that the linear expansion rate was 20.28% at 90 °C and that the anti-swelling rate was 81.16% at room temperature, indicating that it has a strong inhibition ability at both room temperature and at high temperatures. Meanwhile, the possibility of multi-mixed metal hydroxide as a drilling fluid base mud is discussed in this study. We found that 4% M6-Fe exhibited low viscosity, a high YP/PV ratio and high temperature resistance, and its apparent viscosity retention rate reached 100% rolled at 200 °C for 16 h, with a YP/PV ratio of 2.33