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Low platium loading Pt/C catalyst was prepared by direct Pt-embedded carbon xerogel method. The Pt content of the as-prepared Pt/C is about 4.32 wt% and has a typical polycrystalline phase. Textural and structural characteristics of the catalysts were characterized by XRD, EDS and BET. Pt-embedded in carbon xerogel increases the specific surface area and pore volume of the X-Pt/C during carbon gelation and the carbonization process. Electrochemical characteristics of the catalysts for ethanol electrooxidation were measured. The results indicated that the as-prepared 4.32 wt% Pt/C has higher mass current density in ethanol electrooxidation as compared to the 20 wt% Pt/C. This may be due to the high roughness of the Pt surface that is formed during the carbon gelation and carbonization process. [ABSTRACT FROM AUTHOR]

Solid acid catalysts of SO/TiO2/MCM-41 and S2O/TiO2/MCM-41 were prepared via grafting method and sulfate/persulfate promotion. The catalysts exhibited desirable activity and better selectivity for cyclization reaction of pseudoionone compared to traditional SO/TiO2. A combination of XRD, N2 adsorption–desorption and FTIR spectroscopy indicated that the catalysts possess well-ordered mesostructure, and the grafted TiO2 are in highly dispersed amorphous form rather than crystalline phase. For S2O/TiO2/MCM-41 higher S content and more Brønsted acid sites can be achieved by persulfation, which is favorable for the protons participated cyclization reaction. The similar Si–O–Ti–O–S=O structure of all acid sites on pore surface of the catalysts is attributed to the improvement of selectivity in comparison with SO/TiO2. [ABSTRACT FROM AUTHOR]

The path toward Li-ion batteries with higher energy densities will likely involve use of thin lithium (Li)-metal anode (<50 µm thickness), whose cyclability today remains limited by dendrite formation and low coulombic efficiency (CE). Previous studies have shown that the solid-electrolyte interface (SEI) of the Li metal plays a crucial role in Li-electrodeposition and -stripping behavior. However, design rules for optimal SEIs are not well established. Here, using integrated experimental and modeling studies on a series of structurally similar SEI-modifying model compounds, we reveal the relationship between SEI compositions, Li deposition morphology, and CE and identify two key descriptors for the fraction of ionic compounds and compactness, leading to high-performance SEIs.We further demonstrate one of the longest cycle lives to date (350 cycles for 80% capacity retention) for a high specific-energy Li||LiCoO2 full cell (projected >350 watt hours [Wh]/kg) at practical current densities. Our results provide guidance for rational design of the SEI to further improve Li-metal anodes. [ABSTRACT FROM AUTHOR]

The lithium-ion battery was first commercially introduced by Sony Corporation in 1991 using LiCoO2 as the cathode material and mesocarbon microbeads (MCMBs) as the anode material. After continuous research and development for 25 years, lithium-ion batteries have been the dominant energy storage device for modern portable electronics, as well as for emerging applications for electric vehicles and smart grids. It is clear that the success of lithium-ion technologies is rooted to the existence of a solid electrolyte interphase (SEI) that kinetically suppresses parasitic reactions between the lithiated graphitic anodes and the carbonate-based non-aqueous electrolytes. Recently, major attention has been paid to the importance of a similar passivation/protection layer on the surface of cathode materials, aiming for a rational design of high-energy-density lithium-ion batteries with extended cycle/calendar life. In this article, the physical model of the SEI, as well as recent research efforts to understand the nature and role of the SEI are summarized, and future perspectives on this important research field will also be presented. [ABSTRACT FROM AUTHOR]

Accurate modeling of open-circuit-voltage (OCV) plays important roles both in state-of-charge (SOC) estimation and state-of-health (SOH) monitoring for lithium-ion batteries (LIBs). Monotonicity violation in OCV model would lead to inaccurate SOC estimation and ineffective of incremental capacity analysis (ICA) for SOH monitoring. In this study, first-order derivative of OCV, with respect to SOC is introduced to theoretically ensure the satisfaction of monotonicity and a nonlinear semi-infinite programming (NSIP) problem is constructed to parameter estimation. A global optimization approach via restriction of the right-hand side is used to efficiently and globally optimize the NSIP. Both fitting and ICA results demonstrate the effectiveness of the proposed method. Moreover, in comparison to the traditional polynomial and sigmoid models, the NSIP polynomial model is the best choice for performing further SOC estimation and SOH monitoring. The results thus indicate that a NSIP framework for embedding prior knowledge not only provides a promising approach to automatically capture OCV-SOC monotonicity constraint in LIBs, but also serves as a universal methodology for process modeling with the requirements of embedding derivative constraints. [ABSTRACT FROM AUTHOR]

A feasible and scalable two-step method is developed to synthesize LiFeSO4Fy(OH)1-y which could deliver 92 and 80 mA h g-1 when cycled at 1 C and 15 C, respectively. Moreover, with 80% of capacity retention after 2800 cycles at 1 C, this material should be of great interest as a contender to LiFePO4 for use in high power Li-ion batteries. [ABSTRACT FROM AUTHOR]

A double perovskite oxide Sr2CrMoO6-δ (SCM), synthesized using the sol-gel and annealing method with the assistance of citric acid and ethylene diamine tetraacetic acid, was investigated for the first time as an efficient catalyst for rechargeable lithium air batteries. The SCM cathode enables higher specific capacity, lower overpotential and a much better cyclability compared to the pure Super P electrode owing to its excellent electrocatalytic activity towards the formation/decomposition of Li2O2. [ABSTRACT FROM AUTHOR]

A structure optimized Prussian blue analogue Na1.76Ni0.12Mn0.88[Fe(CN)6]0.98 (PBMN) is synthesized and investigated. Coexistence of inactive Ni2+ (Fe-C≡N-Ni group) with active Mn2+/3+ (Fe-C≡N-Mn group) balances the structural disturbances caused by the redox reactions. This cathode material exhibits particularly excellent cycle life with high capacity (118.2 mA h g-1). [ABSTRACT FROM AUTHOR]

A high performance CoO/carbon nanofibers (CNF) composite catalyst was synthesized for Li-O2batteries. For comparison, CoO/BP2000 and CoO/MWNTs were also prepared and investigated to study the influence of carbon supports on the electrochemical performance of the composite catalysts. Electrochemical tests showed that the Li-O2battery with CoO/CNF demonstrated obviously enhanced electrochemical performance than the batteries with CoO/BP2000 and CoO/MWNTs catalysts, which delivered a first discharge capacity of 3882.5mAhgcat-1and remained about 3302.8mAhgcat-1after 8 cycles in the voltage range from 2.0 to 4.2V. More importantly, the cycle stability of the Li-O2battery with CoO/CNF could maintain over 50 cycles when cycled at a fixed capacity of 1000mAhgcat-1. The unique porous nanofiberous structure of CoO/CNF greatly contributed to its high electrocatalytic performance. [ABSTRACT FROM AUTHOR]

Abnormal migration and proliferation of airway smooth muscle cells (ASMCs) in the airway cause airway wall thickening, which is strongly related with the development of airway remodeling in asthma. Clara cell 10?kDa protein (CC10), which is secreted by the epithelial clara cells of the pulmonary airways, plays an important role in the regulation of immunological and inflammatory processes. Previous studies suggested that CC10 protein had great protective effects against inflammation in asthma. However, the effects of CC10 protein on ASMCs migration and proliferation in airway remodeling were poorly understood. In this study, we constructed the pET-22b-CC10 recombinant plasmid, induced expression and purified the recombinant rat CC10 protein from E. coli by Ni2+ affinity chromatography and ion exchange chromatography purification. We investigated the effect of recombinant rat CC10 protein on platelet-derived growth factor (PDGF)-BB-induced ASMCs proliferation and migration. Our results demonstrated that the recombinant CC10 protein could inhibit PDGF-BB-induced cell viability, proliferation and migration. Western blot analysis showed that PDGF-BB-induced activation of cyclin D1 was inhibited by CC10. These findings implicated that CC10 could inhibit increased ASMCs proliferation, and migration induced by PDGF-BB, and this suppression effect might be associated with inhibition of cyclin D1 expression, which might offer hope for the future treatment of airway remodeling. [ABSTRACT FROM AUTHOR]

Low-Pt content (5%) carbon-supported Pt–Ni–TiO2 nanotube electrocatalysts were prepared via a microwave-assisted polyol strategy. Physical and morphological properties of these electrocatalysts were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM), and energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry and chronoamperometry studies clearly suggested that the Pt(5%)–Ni(10%)–TiO2 nanotube (10%) supported by Vulcan XC-72 is better than the commercial 20% Pt/C electrocatalyst for methanol electro-oxidation in direct methanol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

The article presents a study which demonstrates the oxygen reduction reaction activity of cobalt-polypyrrole-toluenesulfonic acid/carbon (Co-PPy-TsOH/C). It states that Co-PPy-TsOH/C is synthesized with p-TsOH-doped PPy/C as a nitrogen (N) rich and morphological support together with cobalt salt. Results show that increase of N-content significantly improve the electrocatalytic activity of Co-PPy-TsOH/C toward ORR compared with Co-PPy/C activity.