Phosphorus-doped carbon/carbon nanotube hybrids as high-performance electrodes for supercapacitors

Magnetic N-doped CNT stabilized Cu2O as a catalyst for N-arylation of nitriles and aryl halides in a biocompatible deep eutectic solvent

This study documented the hydrolysis of nitriles by copper(i) oxide immobilized on nitrogen-doped carbon nanotubes (N-CNT/Fe3O4-Cu2O) to yield corresponding amides in the presence of a deep eutectic solvent (ChOH/Gly). Furthermore, the aforementioned catalyst can facilitate the coupling reaction between aryl halides and amides derived by nitrile hydrolysis. Consequently, the integration of two copper-catalyzed processes can efficiently provide N-aryl amides. Choline hydroxide in a deep eutectic solvent serves as a cost-effective organic catalyst in nitrie hydrolysis by forming hydrogen bonds with nitrile, thereby activating it. The catalyst generated higher to satisfactory product yields. One of the special benefits of the catalyst is that it can be restored through the addition of an external magnetic field.

High mass load of oxygen-enriched microporous hollow carbon spheres as electrode for supercapacitor with solar charging station application

Carbon materials modified with pores and heteroatoms have been pursued as promising electrode for supercapacitors due to the synergic storage of electric double-layer capacitance (EDLC) and pseudocapacitance. A vital problem that the actual effect of pores and heteroatoms on energy storage varies with the carbon matrix used presents in numerous carbon electrodes, but is ignored greatly, which limits their sufficient utilization. Moreover, most of modified carbon electrodes still suffer from severe capacitance degeneration under high mass load caused by the blocked surface and inaccessible bulk phase. Here, we shape an interconnected hollow carbon sphere (HCS) as the matrix by regulating and selectively-etching low molecular weight component in the inhomogeneous precursors, accompanied with the decoration of rich oxygen groups (15.9at%) and micropores (centering at 0.6-1.4 nm). Finite-element calculation and energy storage kinetics reveal the modified HCS electrode exposes accessible dual active surface with highly-matched electrons and ions for pores and oxygen groups to improve both EDLC and pseudocapacitance. Under a commercial-level load of 11.2 mg cm^-2, the HCS exhibits a high specific capacitance of 288.3 F g^-1 at 0.5 A g^-1, performing a retention of 91.8% relative to 314 F g^-1 under 2.8 mg cm^-2 load, applicable for solar charging station to efficiently drive portable electronics.