The poor cycling stability resulting from the large volume expansion caused by lithiation is a critical issue for Si‐based anodes. Herein, we report for the first time of a new yolk–shell structured ...high tap density composite made of a carbon‐coated rigid SiO2 outer shell to confine multiple Si NPs (yolks) and carbon nanotubes (CNTs) with embedded Fe2O3 nanoparticles (NPs). The high tap density achieved and superior conductivity can be attributed to the efficiently utilised inner void containing multiple Si yolks, Fe2O3 NPs, and CNTs Li+ storage materials, and the bridged spaces between the inner Si yolks and outer shell through a conductive CNTs “highway”. Half cells can achieve a high area capacity of 3.6 mAh cm−2 and 95 % reversible capacity retention after 450 cycles. The full cell constructed using a Li‐rich Li2V2O5 cathode can achieve a high reversible capacity of 260 mAh g−1 after 300 cycles.
Improving the conductivity and tap density of yolk–shell‐structured Si/C anodes for lithium‐ion batteries is possible by introducing Fe2O3 nanoparticles (NPs) embedded in carbon nanotube (CNT) networks into the void space between the Si yolks and the outer double shell. A full cell can achieve a high reversible capacity of 260 mAh g−1 after 300 cycles.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A flexible air electrode (FAE) with both high oxygen electrocatalytic activity and excellent flexibility is the key to the performance of various flexible devices, such as Zn–air batteries. A facile ...two‐step method, mild acid oxidation followed by air calcination that directly activates commercial carbon cloth (CC) to generate uniform nanoporous and super hydrophilic surface structures with optimized oxygen‐rich functional groups and an enhanced surface area, is presented here. Impressively, this two‐step activated CC (CC‐AC) exhibits superior oxygen electrocatalytic activity and durability, outperforming the oxygen‐doped carbon materials reported to date. Especially, CC‐AC delivers an oxygen evolution reaction (OER) overpotential of 360 mV at 10 mA cm−2 in 1 m KOH, which is among the best performances of metal‐free OER electrocatalysts. The practical application of CC‐AC is presented via its use as an FAE in a flexible rechargeable Zn–air battery. The bendable battery achieves a high open circuit voltage of 1.37 V, a remarkable peak power density of 52.3 mW cm−3 at 77.5 mA cm−3, good cycling performance with a small charge–discharge voltage gap of 0.98 V and high flexibility. This study provides a new approach to the design and construction of high‐performance self‐supported metal‐free electrodes.
An exceptionally simple two‐step activation method, mild acid oxidation followed by air calcination, is implemented to create a low‐cost flexible air electrode for zinc‐air batteries from commercial carbon cloth. This two‐step‐activated carbon cloth exhibits superior bifunctional oxygen electrocatalytic activity and durability. The corresponding flexible zinc‐air battery achieves a small charge‐discharge voltage gap, remarkable peak power density and good cycling performance.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Electronic structure engineering via integrating two defect structures with opposite modulation effects holds the key to fully unlocking the power of a catalyst. Herein, an interpolation principle is ...proposed to activate CoOOH via W doping and Co vacancies for the oxygen evolution reaction. Density functional theory suggests opposite roles for the W dopant and the Co vacancy but a synergy between them in tuning the electronic states of the Co site, leading to near‐ideal intermediate energetics and dramatically lowered catalytic overpotential. Experimental studies confirm the modulation of the electronic structure and validate the greatly enhanced catalytic activity with a small overpotential of 298.5 mV to drive 50 mA cm−2. The discovery of the interpolation between dopants and vacancies opens up a new methodology to design efficient catalysts for various electrochemical reactions.
An interpolation principle between W dopant and Co vacancy with opposite modulation effect is proposed to tune the electronic structure of CoOOH for enhanced oxygen evolution reaction. As a result, near‐optimal electronic states and near‐ideal intermediate energetics are achieved, leading to high catalytic activity. Such an interpolation principle can open up a new methodology for efficient catalyst design.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The symmetric batteries with an electrode material possessing dual cathodic and anodic properties are regarded as an ideal battery configuration because of their distinctive advantages over the ...asymmetric batteries in terms of fabrication process, cost, and safety concerns. However, the development of high‐performance symmetric batteries is highly challenging due to the limited availability of suitable symmetric electrode materials with such properties of highly reversible capacity. Herein, a triple‐hollow‐shell structured V2O5 (THS‐V2O5) symmetric electrode material with a reversible capacity of >400 mAh g−1 between 1.5 and 4.0 V and >600 mAh g−1 between 0.1 and 3.0 V, respectively, when used as the cathode and anode, is reported. The THS‐V2O5 electrodes assembled symmetric full lithium‐ion battery (LIB) exhibits a reversible capacity of ≈290 mAh g−1 between 2 and 4.0 V, the best performed symmetric energy storage systems reported to date. The unique triple‐shell structured electrode makes the symmetric LIB possessing very high initial coulombic efficiency (94.2%), outstanding cycling stability (with 94% capacity retained after 1000 cycles), and excellent rate performance (over 140 mAh g−1 at 1000 mA g−1). The demonstrated approach in this work leaps forward the symmetric LIB performance and paves a way to develop high‐performance symmetric battery electrode materials.
The symmetric full lithium‐ion battery with the highest capacity (290 mAh g−1) and superior cycling stability (94% capacity retained after 1000 cycles) is designed in this work. The triple‐hollow‐shell structured V2O5 and lithiated LixV2O5 are, respectively, used as cathode and anode to fabricate a high‐performance full symmetric lithium‐ion battery.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The vast majority of the reported hydrogen evolution reaction (HER) electrocatalysts perform poorly under alkaline conditions due to the sluggish water dissociation kinetics. Herein, a hybridization ...catalyst construction concept is presented to dramatically enhance the alkaline HER activities of catalysts based on 2D transition metal dichalcogenides (TMDs) (MoS2 and WS2). A series of ultrathin 2D‐hybrids are synthesized via facile controllable growth of 3d metal (Ni, Co, Fe, Mn) hydroxides on the monolayer 2D‐TMD nanosheets. The resultant Ni(OH)2 and Co(OH)2 hybridized ultrathin MoS2 and WS2 nanosheet catalysts exhibit significantly enhanced alkaline HER activity and stability compared to their bare counterparts. The 2D‐MoS2/Co(OH)2 hybrid achieves an extremely low overpotential of ≈128 mV at 10 mA cm−2 in 1 m KOH. The combined theoretical and experimental studies confirm that the formation of the heterostructured boundaries by suitable hybridization of the TMD and 3d metal hydroxides is responsible for the improved alkaline HER activities because of the enhanced water dissociation step and lowers the corresponding kinetic energy barrier by the hybridized 3d metal hydroxides.
Ultrathin 2D hybrids are designed and prepared via surface modification of monolayer MoS2 and WS2 nanosheets by metal (Ni, Co, Fe, Mn) hydroxides, which form a new class of alkaline hydrogen evolution reaction (HER) electrocatalysts. The surface introduction of metal hydroxides can effectively reduce the kinetic barrier of the prior water dissociation step of the alkaline HER reaction.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Photothermal CO2 hydrogenation to high‐value‐added chemicals and fuels is an appealing approach to alleviate energy and environmental concerns. However, it still relies on the development of ...earth‐abundant, efficient, and durable catalysts. Here, the design of N‐doped carbon‐coated Co nanoparticles (NPs), as a photothermal catalyst, synthesized through a two‐step pyrolysis of Co‐based ZIF‐67 precursor, is reported. Consequently, the catalyst exhibits remarkable activity and stability for photothermal CO2 hydrogenation to CO with a 0.75 mol gcat−1 h−1 CO production rate under the full spectrum of light illumination. The high activity and durability of these Co NPs are mainly attributed to the synergy of the attuned size of Co NPs, the thickness of carbon layers, and the N doping species. Impressively, the experimental characterizations and theoretical simulations show that such a simple N‐doped carbon coating strategy can effectively facilitate the desorption of generated CO and activation of reactants due to the strong photothermal effect. This work provides a simple and efficient route for the preparation of highly active and durable nonprecious metal catalysts for promising photothermal catalytic reactions.
N‐doped carbon‐coated Co nanoparticles, derived from two‐step pyrolysis of ZIF‐67 precursor, exhibit highly efficient and durable catalytic performance for photothermal hydrogenation of CO2. As verified by experimental observations and theoretical simulations, such a simple N‐doped carbon coating strategy can effectively promote the desorption of CO and activation of CO2 and H2 molecules due to the strong photothermal effect.
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The United States government spends over $85 billion annually on treating non-dialysis chronic kidney disease (CKD). Patients with CKD are prescribed a multitude of medications to manage numerous ...comorbidities associated with CKD. Thus, this study aims to investigate the association between polypharmacy and health-related quality of life (HRQoL) in non-dialysis CKD patients. This cross-sectional study utilized data from the Medical Expenditure Panel Survey (MEPS) from 2010 through 2019. We classified polypharmacy into three groups based on the number of medication classes: less than or equal to 4 (minor polypharmacy), 5 through 9 (major polypharmacy), and greater than or equal to 10 (hyperpolypharmacy). To measure HRQoL, a Physical Component Summary (PCS) and a Mental Component Summary (MCS) were obtained from the 12-item Short-Form Health Survey version 2 and Veteran's Rand 12 item. We applied multivariable ordinary least squares regression to assess the association between polypharmacy and HRQoL in non-dialysis CKD patients. A total of 649 CKD patients (weighted n = 667,989) were included. Patients with minor polypharmacy, major polypharmacy, and hyperpolypharmacy were 22.27%, 48.24%, and 29.48%, respectively. Major polypharmacy and hyperpolypharmacy were significantly and negatively associated with lower PCS scores when compared with minor polypharmacy Beta = -3.12 (95% CI: -3.62, -2.62), p-value<0.001; Beta = -4.13 (95CI: -4.74, -3.52), p-value<0.001. Similarly, major polypharmacy and hyperpolypharmacy were significantly and negatively associated with lower MCS scores when compared to minor polypharmacy Beta = -0.38 (95% CI: -0.55, -0.20), p-value<0.001; Beta = -1.70 (95% CI: -2.01, -1.40), p-value<0.001. The top 5 classes of medications used by CKD patients were antihyperlipidemic (56.31%), beta-adrenergic blockers (49.71%), antidiabetics (42.14%), analgesics (42.17%), and diuretics (39.65%). Our study found that both major polypharmacy and hyperpolypharmacy were associated with lower HRQoL among non-dialysis CKD patients. This study highlights the need for further evaluation of the combination of medications taken by non-dialysis CKD patients to minimize unnecessary and inappropriate medication use.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Rechargeable aqueous zinc‐ion batteries (ZIBs) are promising in stationary grid energy storage due to their advantages in safety and cost‐effectiveness, and the search for competent cathode materials ...is one core task in the development of ZIBs. Herein, the authors design a 2D heterostructure combining amorphous vanadium pentoxide and electrochemically produced graphene oxide (EGO) using a fast and scalable spray drying technique. The unique 2D heterostructured xerogel is achieved by controlling the concentration of EGO in the precursor solution. Driven by the improved electrochemical kinetics, the resultant xerogel can deliver an excellent rate capability (334 mAh g−1 at 5 A g−1) as well as a high specific capacity (462 mAh g−1 at 0.2 A g−1) as the cathode material in ZIB. It is also shown that the coin cell constructed based on spray‐dried xerogel can output steady, high energy densities over a broad power density window. This work provides a scalable and cost‐effective approach for making high performance electrode materials from cheap sources through existing industrialized materials processing.
The authors make use of a rapid spray drying technique to produce a 2D heterostructure consisting of amorphous vanadium pentoxide and electrochemically produced graphene oxide (EGO) for high performance cathodes of aqueous zinc‐ion batteries. The control of the concentration of EGO in the precursor solution is demonstrated as a key factor in constructing such a 2D heterostructure.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Background: In Bangladesh, there is a scarcity of nationally representative data on the burden of chronic obstructive pulmonary disease (COPD). Methods: To estimate the COPD prevalence in rural ...settings, this cross-sectional, population-based study was conducted in all eight administrative divisions of Bangladesh, and involved adults aged 40 years and above. By using multi-stage random sampling, 2,458 individuals were enrolled. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines were used to diagnose COPD based on post-bronchodilator lung function, while additional participant data was gathered through computer-assisted personal interviews. Results: A 2% COPD prevalence (95% CI: 1.45, 2.55) was found in the study sample with a statistically significant difference between males (2.7%; 95% CI: 1.8, 3.6) and females (1.2%; 95% CI: 0.59, 1.81). Increasing age significantly inflated the odds of having COPD irrespective of sex (OR: 1.03; 95% CI: 1.00, 1.05; P value < 0.05). Furthermore, prevalence of COPD was higher among manual workers, cigarette smokers, and those that used the indoor kitchen and did not have a primary education. Sex-based analysis showed that smokeless tobacco consumption was significantly associated with COPD occurrence among males (OR: 2.14; 95% CI: 1.05, 4.37; P value < 0.05), but not females. Further, using an indoor kitchen increased the odds of developing COPD by 400% among female participants (OR: 4.39; 95% CI: 1.37, 14.10; P value < 0.05). Conclusion: This study provides a comprehensive sex-based estimation of COPD prevalence among rural population and imparts significant contribution to the growing database on COPD prevalence in Bangladesh.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Lithium‐selenium (Li−Se) batteries are promising energy storage devices. However, the long‐term durability and high‐rate performance of the Se cathode have been limited by significant volume ...expansion and the troublesome shuttle effect of polyselenides during repeated charging/discharging processes. To revolutionize these issues, we applied a top‐down strategy through the in‐situ trapping of amorphous Se within bubble‐like carbon (BLC) frameworks, which can radically minimize the presence of surface‐absorbed Se while enhancing Se loading capacity. This ingenious technique successfully encapsulates all Se species within carbon nanoshells, creating a distinct half‐filled core‐shell structure known as Se@void@BLC. This in‐situ trapping approach ensures the efficient management of Se volume changes during repeated discharge and charge cycles. Moreover, an extraordinary Se loading capacity of up to 65.6 wt% is reached. Using the Se@void@BLC as cathode for Li−Se battery, we achieve a high initial Columbic efficiency of 84.2 %, a high reversible capacity of 585 mAh g−1, and an ultralow capacity decay of only 0.0037 % per cycle during 4000 cycles at 10 A g−1.
This work presents a novel “top–down” approach to in–situ confine Se within bubble–like carbon frameworks to minimize the shuttle effect and volume expansion of Se cathode in Li‐Se batteries. The resultant Se@void@BLNC shows a unique half‐filled core‐shell structure than ensures an ultra‐stable cycling performance of almost 100% capacity reservation during 4000 cycles at 10 A g−1.
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