Sustainable Electrochemical NO Capture and Storage System Based on the Reversible Fe2+/Fe3+-EDTA Redox Reaction

The removal of nitric oxide (NO), which is an aggregation agent for fine dust that causes air pollution, from exhaust gas has been considered an important treatment in the context of environmental conservation. Herein, we propose a sustainable electrochemical NO removal system based on the reversible Fe2+/Fe3+-ethylenediamine tetraacetic acid (EDTA) redox reaction, which enables continuous NO capture and storage at ambient temperature without the addition of any sacrificial agents. We have designed a flow-type reaction system in which the NO absorption and emission can be separately conducted in the individual reservoirs of the catholyte and anolyte with the continuous regeneration of Fe2+-EDTA by the electrochemical reduction in Fe3+-EDTA. A continuous flow reaction using a silver cathode and glassy carbon anode showed that the concentrations of Fe2+ and Fe3+-EDTA in the electrolyte were successfully maintained at a 1:1 ratio, which demonstrates that the proposed system can be applied for continuous NO capture and storage.

PPy coated nanoflower like CuCo2O4 based on in situ growth of nanoporous copper for high-performance supercapacitor electrodes

General CuCo2O4 electrodes suffer a very low reversible capacity and poor cycling stability because of easily fading phenomena and volume change during cycling. To optimize the electrode, a facile method is conducted to fabricate a novel electrode of Cu@CuCo2O4@polypyrrole (Cu@CCOP) nanoflowers. Due to larger specific surface area and more electrochemical reactive areas of Cu@CCOP nanoflowers, the pseudocapacitance of the in-situ grown Cu@CCOP (912 F g-1 at 2 A g-1) is much higher than the pristine CuCo2O4 (CCO) (618 F g-1 at 2 A g-1). Remarkably, the Cu@CCOP (cathode) and active carbon (anode) are used to assemble an asymmetric supercapacitor, which exhibits a relatively high energy density of 90 Wh kg-1 at a power density of 2519 W kg-1 and 35 Wh kg-1 at a high-power density of 9109 W kg-1, and excellent cycling stability (about 90.4% capacitance retention over 10000 cycles). The prominent performance of Cu@CCOP makes it as a potential electrode for supercapacitor.

Preparation of MoB2 Nanoparticles by Electrolysis of MoS2/B Mixture in Molten NaCl-KCl at 700 oC

MoB2 is synthesized by the electrochemical reduction of solid MoS2/B mixture in molten NaCl-KCl at 700 oC. Unlike the traditional methods, the electrolysis method employs the low-cost MoS2 feedstock and the boronization reaction happens at a low temperature of 700 oC. The electrochemically induced boronization involves two steps: the electrochemical desulfurization to generate Mo and the reaction of Mo with B to form MoB2. The S2- released from the reduction of MoS2 transfers to the carbon anode and is oxidized to sulfur gas, realizing a green synthetic process. In addition, the influences of molar ratio of MoS2 and amorphous boron and electrolysis cell voltage on the phase composition and morphology of electrolytic products were studied. The obtained MoB2 particles possess a uniform nodular morphology. Overall, this paper provides a straightforward and green process to prepare MoB2 nanoparticles using economically affordable raw materials at low temperature, and this method can be extended to prepare other borides.