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Titanium oxynitride carbon composite nanofibers (TiON/C-CNFs) were synthesised with electrospinning and subsequent heat treatment in ammonia gas. In situ four-probe electrical conductivity measurements of individual TiON/C-CNFs were performed. Additionally, the TiON/C-CNFs were thoroughly analysed with various techniques, such as X-ray and electron diffractions, electron microscopies and spectroscopies, thermogravimetric analysis and chemical analysis to determine the crystal structure, morphology, chemical composition, and N/O at. ratio. It was found that nanofibers were composed of 2–5 nm sized titanium oxynitride (TiON) nanoparticles embedded in an amorphous carbon matrix with a small degree of porosity. The average electrical conductivity of a single TiON/C-CNF was 1.2 kS/m and the bulk electrical conductivity of the TiON/C-CNF fabric was 0.053 kS/m. From the available data, the mesh density of the TiON/C-CNF fabric was estimated to have a characteristic length of 1.0 µm and electrical conductivity of a single TiON/C-CNF was estimated to be from 0.45 kS/m to 19 kS/m. The electrical conductivity of the measured TiON/C-CNFs is better than that of amorphous carbon nanofibers and has ohmic behaviour, which indicates that it can effectively serve as a new type of support material for electrocatalysts, batteries, sensors or supercapacitors. [ABSTRACT FROM AUTHOR]

The rational design of electrochemical oxygen evolution reaction (OER) electrocatalyst is essential for the development of efficient and sustainable electrochemical energy conversion, storage and electrolysis applications. One of the remaining limitations of the low‐temperature electrolyzers is the large amounts of highly scarce and expensive iridium used as the OER electrocatalysts. This could be solved by applying much smaller amounts of iridium on efficient and stable support. Here we present a very promising functionality of titanium oxynitride (TiONx) high‐surface‐area support that effectively disperses the iridium nanoparticles, exhibits good intrinsic electrical conductivity and stability and thus promises efficient reduction of the noble‐metal loading in electrolyzers gas diffusion electrodes. The new nanocomposite made of approximately 3 nm‐sized iridium nanoparticles finely dispersed on TiONx support is produced using a novel synthetic route. Extensive characterization shows that the new composites exhibit an electronic interaction with the support and, ultimately, a high OER performance in acidic media. [ABSTRACT FROM AUTHOR]

B The Front Cover b shows titanium oxynitride nanoribbons with finely dispersed iridium nanoparticles as an oxygen evolution reaction electrocatalyst. In their Full Paper, Nejc Hodnik, Miran Gaberscek and co-workers describe how Ir nanoparticles dispersed on the titanium oxynitride nanoribbon show promise to be used as proton exchange membrane electrolysis anode electrocatalyst. Electrocatalysis, PEM electrolyzers, oxygen evolution reaction, titanium oxynitride, stability. [Extracted from the article]

• An efficient TiO x N y electro catalyst was synthesized in the immobilized form. • In-depth characterization of the active titanium oxynitride catalyst was performed. • A continuous-flow microreactor was used to study phenol degradation. • Oxidation mechanism was proposed including contribution of Cl− reaction pathways. • Optimal reactor dimensions were determined by the model. In this study a novel titanium oxynitride electrocatalyst was synthesized and its electrocatalytic activity for the degradation of phenol was evaluated. A highly conductive and efficient Ti–O–N electrocatalyst was prepared in a three-step synthesis. A titanium coil was anodized to grow TiO 2 nanotubes, which were then annealed in air to convert the amorphous structure to anatase and afterwards annealed in ammonia to obtain the final Ti–O–N catalyst. This was characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). To evaluate its degradation capabilities, the electrocatalytic oxidation of the phenol was performed inside a coil-type electrocatalytic microreactor. Phenol conversions of up to 95% of the initial 0.4 mmol L–1 of phenol were achieved at the studied applied electric potentials (1–16 V), NaCl concentrations (0.51–5.12 g L–1) and flow rates(20–500 μL min–1). The mechanism of electrocatalytic oxidation was proposed in a three-dimensional reactor model that accurately describes the electrocatalytic degradation of phenol at the Ti–O–N anode in the presence of NaCl in the phenol solution. It was shown that both OH*– and OCl*–mediated reaction mechanisms contribute to the phenol's degradation, while at high NaCl concentrations (5 g L–1) the latter is dominant. In addition, the optimal reactor design is determined by studying the mass-transfer limitation with the model. [ABSTRACT FROM AUTHOR]