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Molybdenum (Mo) carbide-based electrocatalysts are considered promising candidates to replace Pt-based materials toward the hydrogen evolution reaction (HER). Among different crystal phases of Mo carbides, although MoC exhibits the highest catalytic performance, the activity is still restricted by the strong Mo-H bonding. To weaken the strong Mo-H bonding, creating abundant MoC/MoC interfaces and/or doping a proper amount of electron-rich (such as N and P) dopants into the MoC crystal lattice are effective because of the electron transfer from Mo to surrounding C in carbides and/or N/P dopants. In addition, Mo carbides with well-defined nanostructures, such as one-dimensional nanostructure, are desirable to achieve abundant catalytic active sites. Herein, well-defined N,P-codoped MoC/MoC nanofibers (N,P-Mo C NF) were prepared by pyrolysis of phosphomolybdic ([PMoO], PMo) acid-doped polyaniline nanofibers at 900 °C under an Ar atmosphere, in which the hybrid polymeric precursor was synthesized via a facile interfacial polymerization method. The experimental results indicate that the judicious choice of pyrolysis temperature is essential for creating abundant MoC/MoC interfaces and regulating the N,P-doping level in both Mo carbides and carbon matrixes, which leads to optimized electronic properties for accelerating HER kinetics. As a result, N,P-Mo C NF exhibits excellent HER catalytic activity in both acidic and alkaline media. It requires an overpotential of only 107 and 135 mV to reach a current density of 10 mA cm in 0.5 M HSO and 1 M KOH, respectively, which is comparable and even superior to the best of Mo carbide-based electrocatalysts and other noble metal-free electrocatalysts.

Malakoplakia is a rare, granulomatous condition most commonly found in the genitourinary tract. It can present in a myriad of ways depending on the organ involved, thus presenting a huge diagnostic challenge. We present 4 patients with genitourinary malakoplakia, who manifested with recurrent urinary tract infection (UTI) and hematuria in all except one, who presented with hydronephrosis secondary to a large pelvic mass. We discuss the need for a high index of suspicion and careful scrutiny of histology to order to avoid misdiagnosis as simple long term antibiotics are an effective treatment in all but those with large pelvic masses.

We report here the fabrication of CuO nanowires and their use as efficient electrocatalyst for the oxygen evolution reaction (OER) or as precursor for preparation of Cu3P nanowires for the hydrogen evolution reaction (HER). The surface-bound Cu­(OH)2 nanowires are in situ grown on a three-dimensional copper foam (CF) by anodic treatment, which are then converted to CuO nanowires by calcination in air. The direct growth of nanowires from the underlying conductive substrate can eliminate the use of any conductive agents and binders, which ensures good electrical contact between the electrocatalyst and the conductive substrate. The hierarchically nanostructured Cu-based electrode exhibits excellent catalytic performance toward OER in 1 M KOH solution. Phosphorization of the CuO/CF electrode generates the Cu3P/CF electrode, which can act as an excellent electrocatalyst for HER in 1 M KOH. An alkaline electrolyzer is constructed using CuO and Cu3P nanowires coated copper foams as anode and cathode, which can realize overall water splitting with a current density of 102 mA/cm2 at an applied cell voltage of 2.2 V.

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