Metallic germanium is a promising anode material in secondary lithium-ion batteries (LIBs) due to its high theoretical capacity (1623 mAh/g) and low operating voltage, coupled with the high lithium-ion diffusivity and electronic conductivity of lithiated Ge. Here, the lithiation mechanism of micron-sized Ge anodes has been investigated with X-ray diffraction (XRD), pair distribution function (PDF) analysis, and in-/ex-situ high-resolution 7Li solid-state nuclear magnetic resonance (NMR), utilizing the structural information and spectroscopic fingerprints obtained by characterizing a series of relevant Li x Ge y model compounds. In contrast to previous work, which postulated the formation of Li9Ge4 upon initial lithiation, we show that crystalline Ge first reacts to form a mixture of amorphous and crystalline Li7Ge3 (space group P3212). Although Li7Ge3 was proposed to be stable in a recent theoretical study of the Li–Ge phase diagram (MorrisA. J.GreyC. P.PickardC. J. Morris, A. J. Grey, C. P. Pickard, C. J. 054111Phys. Rev. B: Condens. Matter Mater. Phys.201490), it had not been identified in prior experimental studies. Further lithiation results in the transformation of Li7Ge3, via a series of disordered phases with related structural motifs, to form a phase that locally resembles Li7Ge2, a process that involves the gradual breakage of the Ge–Ge bonds in the Ge–Ge dimers (dumbbells) on lithiation. Crystalline Li15Ge4 then grows, with an overlithiated phase, Li15+δGe4, being formed at the end of discharge. This study provides comprehensive experimental evidence, by using techniques that probe short-, medium-, and long-range order, for the structural transformations that occur on electrochemical lithiation of Ge; the results are consistent with corresponding theoretical studies regarding stable lithiated Li x Ge y phases.

Electrochemical water splitting is promising for utilizing intermittent renewable energy. The sluggish kinetics of the oxygen evolution reaction (OER), however, is a bottleneck in obtaining high efficiency. Only a few OER electrocatalysts have been developed for the use in acidic media despite the importance of a proton exchange membrane (PEM) water electrolyzer. IrO 2 is the only material that is both active and stable for the OER in highly corrosive acidic conditions. Herein, a facile and scalable synthesis of ultrathin IrO 2 nanoneedles is reported with a diameter of 2 nm using a modified molten salt method. The activity and durability for the OER are significantly enhanced on the ultrathin IrO 2 nanoneedles, compared to conventional nanoparticles. The ultrathin nanoneedles are successfully introduced to a PEM electrolyzer single cell with the enhanced cell performance.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.

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Abstract. BACKGROUND: Urinary incontinence is a common problem among the elderly and patients with neurologic disability. The conventional urinary incontinence aids, such as urine-absorbing diapers, pads, and indwelling catheters, frequently cause hygienic problems. OBJECTIVE: To study the safety and efficacy of a new automatic urine disposal system that can suction and store the urine in a separate container for future disposal. METHODS: An electromechanical urine disposal system that can collect and transport the urine and cleanse and air-dry the external genitalia was developed. The hygienic effects of using this system were studied in 8 participants after 3 months of use. RESULTS: The caregivers of all 8 patients reported improved hygiene of their patients. None of the patients suffered from decubitus ulcers, and skin erythema was absent in 4 patients, while markedly decreased in the other 4 patients when compared with the use of urine-absorbing diapers. Four patients experienced minor urine leakage that was manageable with concurrent use of either diapers or bed pads. CONCLUSIONS: The use of an electromechanical urine disposal system relieves the caregiver from night care, as the urine is automatically collected and stored for disposal the next day. The system improves the hygiene of the patient, as the urine is immediately suctioned and the external genitalia is cleansed and dried after urination.

Coffee is one of the largest agricultural products; however, the majority of the produced coffee is discarded as waste sludge by beverage manufacturers. Herein, we report the use of graphitic porous carbon materials that have been derived from waste coffee sludge for developing an energy storage electrode based on a hydrothermal recycling procedure. Waste coffee sludge is used as a carbonaceous precursor for energy storage due to its greater abundance, lower cost, and easier availability as compared to other carbon resources. The intrinsic fibrous structure of coffee sludge is based on cellulose and demonstrates enhanced ionic and electronic conductivities. The material is primarily composed of cellulose-based materials along with several heteroatoms; therefore, the waste sludge can be easily converted to functionalized carbon. The production of unique graphitic porous carbon by hydrothermal carbonization of coffee sludge is particularly attractive since it addresses waste handling issues, offers a cheaper recycling method, and reduces the requirement for landfills. Our investigations revealed that the graphitic porous carbon electrodes derived from coffee sludge provide a specific capacitance of 140 F g−1, with 97% retention of the charge storage capacity after 1500 cycles at current density of 0.3 A g−1.