Titanium-Based Static Mixer Electrodes to Improve the Current Density of Slurry Electrodes

Complex geometries for electrodes are a great challenge in electrochemical applications. Slurry electrodes have been one example, which use complex flow distributors to improve the charge transfer between the current collector and the slurry particles. Here we use titanium-based flow distributors produced by indirect 3D-printing to improve further the electron transfer from highly conductive flow distributors to the slurry particles for a vanadium redox flow application. The titanium static mixers are directly coated with graphite to increase the activity for vanadium redox reactions. Increasing layers of graphite have shown an optimum for the positive and negative electrolytes. The application of heat treatment on the electrodes improves the anodic and cathodic current peaks drastically. Testing the highly conductive static mixers in a self-made redox flow cell results in 110 mA cm−2 discharge polarization

First report of the exotic blue land planarian, Caenoplana coerulea (Platyhelminthes, Geoplanidae), on Menorca (Balearic Islands, Spain)

In April 2009 two specimens of a terrestrial flatworm were collected from under a rock in an orchard at Ciutadella de Menorca on the easternmost Balearic island of Menorca (Spain). Their external morphology suggested that both specimens belonged to the invasive blue planarian Caenoplana coerulea, a species which is native to eastern Australia. Sequence data of a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) and of the entire 18S ribosomal RNA confirm its identification. This is one of the first records of the species in Europe where it has only been found in one locality in the United Kingdom, France and NE Spain

Influence of the Composition and Preparation of the Rotating Disk Electrode on the Performance of Mesoporous Electrocatalysts in the Alkaline Oxygen Reduction Reaction

We report a systematic study of the influence of the composition and preparation method of the electrocatalyst layer deposited on the rotating (ring) disk electrodes (RDE/RRDE) employed in the alkaline oxygen reduction reaction (ORR). To investigate and rationalize the generally underestimated role of these factors on the ORR performance of mesoporous electrocatalysts, we studied the activity and selectivity of nitrogen-doped ordered mesoporous carbon as a function of the loading of electrocatalyst and of binder, of the type of binder, and of the addition order of the components onto the electrode. The use of an anion-exchange polymer (Fumion FAA-3 (R)) as the binder instead of the commonly employed Nafion (R) increased the selectivity towards H2O2 and led to a lower kinetic current density. In addition, higher selectivity towards H2O was observed when increasing the loading of the catalyst and of the binder, although the latter resulted in a decreased kinetic current density. These results prove the crucial effect of the composition and preparation method of the layer deposited on the electrode on the ORR performance of the mesoporous electrocatalyst and can provide useful guidelines in view of the translation of the results of RDE studies to an alkaline fuel-cell setup

Covalent triazine framework/carbon nanotube hybrids enabling selective reduction of CO2 to CO at low overpotential

Electrochemical reduction of CO2 provides a way to generate base chemicals from an abundant C1-source under mild conditions, whilst at the same time mitigating CO2 emissions. In this work, a novel class of tailorable, porous electrocatalysts for this process is proposed. Covalent triazine frameworks (CTFs) are grown in situ onto functionalized multiwalled carbon nanotubes. Hydroxyl groups decorating the surface of the multiwalled carbon nanotubes facilitate intimate contact between the carbon nanotubes and CTF, thus promoting efficient electron transfer. The novel hybrid materials generate CO with a faradaic efficiency up to 81% at an overpotential of 380 mV. The selectivity of the electrocatalysts could be linked to the amount of nitrogen present within the framework