Lightweight Carbon-Metal-Based Fabric Anode for Lithium-Ion Batteries.

Lithium-ion battery electrodes are typically manufactured via slurry casting, which involves mixing active material particles, conductive carbon, and a polymeric binder in a solvent, followed by casting and drying the coating on current collectors (Al or Cu). These electrodes are functional but still limited in terms of pore network percolation, electronic connectivity, and mechanical stability, leading to poor electron/ion conductivities and mechanical integrity upon cycling, which result in battery degradation. To address this, we fabricate trichome-like carbon-iron fabrics via a combination of electrospinning and pyrolysis. Compared with slurry cast Fe2O3 and graphite-based electrodes, the carbon-iron fabric (CMF) electrode provides enhanced high-rate capacity (10C and above) and stability, for both half cell and full cell testing (the latter with a standard lithium nickel manganese oxide (LNMO) cathode). Further, the CMFs are free-standing and lightweight; therefore, future investigation may include scaling this as an anode material for pouch cells and 18,650 cylindrical batteries.

Rational design of hierarchically nanostructured NiTe@CoxSy composites for hybrid supercapacitors with impressive rate capability and robust cycling durableness.

The hierarchically nanostructured NiTe@CoxSy composites are constructed on a foamed nickel substrate by a two-step electrode preparation process. Structural characterization shows the dense growing of CoxSy nanosheets around NiTe nanorods forms a hierarchical nanostructure which possesses synergetic effects from both compositional and structural complementarity, more pathways for ion/electrolyte transport, richer redox active sites, and better conductivity. Thanks to the rational design of this hierarchical structure, NiTe@CoxSy delivers a high areal capacitance of 7.7F cm-2 at 3 mA cm-2 and achieves the improved capacitance retention of 97.9% after 10,000 cycles. Of particular importance is the successful fabrication of NiTe@CoxSy//activated carbon hybrid supercapacitors. This hybrid device has a wide operating voltage window, high areal energy density of 0.48 mWh cm-2 at 2.55 mW cm-2, impressive rate capability of 62.3% even after a 20-fold increase of the current density, and a 115.1% of initial capacitance retention after 15,000 cycles. Meanwhile, two tandem such hybrid devices can easily drive a pair of mini fans or light up a heart-like pattern assembled by 10 red LEDs. These experimental results not only demonstrate that the hierarchically nanostructured NiTe@CoxSy composites can serve as a prospective candidate electrode; but also develop a novel strategy about how to achieve high-performance stockpile equipment by rationale designing a desirable nanostructures.

Hybrid Redox Flow Cells with Enhanced Electrochemical Performance via Binderless and Electrophoretically Deposited Nitrogen-Doped Graphene on Carbon Paper Electrodes.

Hybrid redox flow cells (HRFC) are key enablers for the development of reliable large-scale energy storage systems; however, their high cost, limited cycle performance, and incompatibilities associated with the commonly used carbon-based electrodes undermine HRFC's commercial viability. While this is often linked to lack of suitable electrocatalytic materials capable of coping with HRFC electrode processes, the combinatory use of nanocarbon additives and carbon paper electrodes holds new promise. Here, by coupling electrophoretically deposited nitrogen-doped graphene (N-G) with carbon electrodes, their surprisingly beneficial effects on three types of HRFCs, namely, hydrogen/vanadium (RHVFC), hydrogen/manganese (RHMnFC), and polysulfide/air (S-Air), are revealed. RHVFCs offer efficiencies over 70% at a current density of 150 mA cm-2 and an energy density of 45 Wh L-1 at 50 mA cm-2, while RHMnFCs achieve a 30% increase in energy efficiency (at 100 mA cm-2). The S-Air cell records an exchange current density of 4.4 × 10-2 mA cm-2, a 3-fold improvement of kinetics compared to the bare carbon paper electrode. We also present cost of storage at system level compared to the standard all-vanadium redox flow batteries. These figures-of-merit can incentivize the design, optimization, and adoption of high-performance HRFCs for successful grid-scale or renewable energy storage market penetration.

Atropine 0.01% Eye Drops for Myopia Control in American Children: A Multiethnic Sample Across Three US Sites.

INTRODUCTION: Topical atropine eye drops at low concentrations have been shown to slow myopia progression in East Asian studies. This study explored the effect of atropine 0.01% eye drops on controlling myopia progression in a multiethnic cohort of children in the USA. METHODS: A multicenter retrospective case-control study (n = 198) quantified the effect of adding nightly atropine 0.01% eye drops to treatment as usual on the progression of childhood (ages 6-15 years) myopia. Cases included all children treated with atropine for at least 1 year. Controls were matched to cases on both age (± 6 months) and baseline spherical equivalent refraction (SER) (± 0.50 diopters, D) at treatment initiation. The primary endpoint was the average SER myopia progression after 1, 1.5, and 2 years of therapy. A secondary outcome was the percentage of subjects with a clinically significant worsening of myopia, defined as a greater than - 0.75 D SER increase in myopia. RESULTS: The average baseline SERs for the atropine (n = 100) and control (n = 98) groups were similar (- 3.1 ± 1.9 D and - 2.8 ± 1.6 D, respectively) (p = 0.23). The average SER increase from baseline was significantly less for the atropine group than the control group at year 1 (- 0.2 ± 0.8 D compared with - 0.6 ± 0.4 D, p < 0.001) and at year 2 (- 0.3 ± 1.1 D compared with - 1.2 ± 0.7 D, p < 0.001). Secondary analysis at year 2 revealed that 80% of the control group vs. 37% of the atropine group experienced clinically significant worsening myopia of at least - 0.75 D (p < 0.001). There were no major safety issues reported in either group. CONCLUSION: Similar to results reported in Asia, atropine 0.01% eye drops significantly reduced myopia progression in a cohort of US children over 2 years of treatment. FUNDING: Nevakar, Inc. Plain language summary available for this article.

The electrochemical behaviour of ferrocene in deep eutectic solvents based on quaternary ammonium and phosphonium salts.

The electrochemical behaviour of ferrocene (Fc) is investigated in six different deep eutectic solvents (DESs) formed by means of hydrogen bonding between selected ammonium and phosphonium salts with glycerol and ethylene glycol. Combinations of cyclic voltammetry and chronoamperometry are employed to characterise the DESs. The reductive and oxidative potential limits are reported versus the Fc/Fc(+) couple. The diffusion coefficient, D, of ferrocene in all studied DESs is found to lie between 8.49 × 10(-10) and 4.22 × 10(-8) cm(2) s(-1) (these do not change significantly with concentration). The standard rate constant for heterogeneous electron transfer across the electrode/DES interface is determined to be between 1.68 × 10(-4) and 5.44 × 10(-4) cm s(-1) using cyclic voltammetry. These results are of the same order of magnitude as those reported for other ionic liquids in the literature.

Bovine hydroxyapatite orbital implant: a preliminary report.

PURPOSE: To determine the safety and efficacy of bovine hydroxyapatite as an orbital implant material. METHODS: Prospective, consecutive case series of patients undergoing enucleation, evisceration, or secondary orbital implantation. A motility peg was placed in all consenting candidates. Patients were followed 1 week, 1 month, and several months after surgery for signs of inflammation, infection, extrusion, or other complication. RESULTS: Twenty-seven patients received a bovine hydroxyapatite orbital implant. Magnetic resonance imaging was obtained in 3 patients (3 orbits) approximately 4 weeks after surgery and showed signs of peripheral fibrovascular ingrowth in all three cases. Magnetic resonance imaging was obtained in 9 patients (9 orbits) 4 to 12 months after surgery and showed signs of incomplete fibrovascular ingrowth in 1 of 9 (11%) cases, subtotal fibrovascular ingrowth in 2 of 9 (22%) cases, and complete fibrovascular ingrowth in 6 of 9 (67%) of cases. Complications included postoperative chemosis in 3 cases (11%) and exposure requiring reoperation in 2 cases (7%). Motility peg placement was performed successfully in 5 patients (5 orbits). CONCLUSIONS: Bovine hydroxyapatite appears to be a safe and effective orbital implant material. The material appears to be biocompatible and nonallergenic. Bovine hydroxyapatite allows for fibrovascular integration and motility peg placement.