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Precise control of pore volume and size of carbon nanoscale materials is crucial for achieving high capacity and rate performances of charge/discharge. In this paper, starting from the unique mechanism of the role of In, Zn combination, and carboxyl functional groups in the formation of the lumen and pore size, the composition of InZn-MIL-68 is regulated to precisely tune the diameter and wall pore size of the hollow carbon tubes. The hollow carbon nanotubes (CNT) with high-capacity storage and fast exchange of Na+ ions and charges are prepared. The CNT possess ultra-high specific capacitance and ultra-long cycle life and also offer several times higher Na+ ion storage capacity and rate performance than the existing CNTs. Density functional theory calculations and tests reveal that these superior characteristics are attributed to the spacious hollow structure, which provides sufficient space for Na+ storage and the tube wall's distinctive porosity of tube wall as well as open ends for facilitating Na+ rapid desorption. It is believed that precise control of sub-nanopore volume and pore size by tuning the composition of the carbon materials derived from bimetallic metal-organic frameworks (MOFs) will establish the basis for the future development of high-energy density and high-power density supercapacitors and batteries.
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Metal-air secondary batteries with ultrahigh specific energies have received vast attention and are considered new promising energy storage. The slow redox reactions between oxygen-water molecules lead to low energy efficiency (55-71%) and limited applications. Herein, it is proposed that the MIL-68(In)-derived porous carbon nanotube supports the CoNiFeP heteroconjugated alloy catalyst with an overboiling point electrolyte to achieve the ultrahigh oxidation rate of water molecules. Structural characterization and density functional theory calculations reveal that the new catalyst greatly reduces the free energy of the process, and the overboiling point further accelerates the dissociation of OâH and hydrogen bonds, and the release of O2 molecules, achieving an extra-low overpotential of 110 mV@10 mA cm-2 far lower than commercial Ir/C catalysts of 192 mV at 125 °C and state-of-the-art. Furthermore, the energy efficiency of assembled rechargeable zinc-air batteries begins to break through at 85 °C, jumps at 100 °C, and reaches ultrahigh energy efficiency of 88.1% at 125 °C with an ultralow decay rate of 0.0068% after 150 cycles far superior to those of reported metal-air batteries. This work provides a new catalyst and electrolyte joint-design strategy and reexamines the battery operating temperature to construct higher energy efficiency for secondary fuel cells.
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Multiporous metal-organic frameworks (MOFs) have emerged as a subclass of highly crystalline inorganic-organic materials, which are endowed with high surface areas, tunable pores, and fascinating nanostructures. Heterostructured MOF-on-MOF composites are recently becoming a research hotspot in the field of chemistry and materials science, which focus on the assembly of two or more different homogeneous or heterogeneous MOFs with various structures and morphologies. Compared with one single MOF, the dual MOF-on-MOF composites exhibit unprecedented tunability, hierarchical nanostructure, synergistic effect, and enhanced performance. Due to the difference of inorganic metals and organic ligands, the lattice parameters in a, b, and c directions in the single crystal cells could bring about subtle or large structural difference. It will result in the composite material with distinct growth methods to obtain secondary MOF grown from the initial MOF. In this review, the authors wish to mainly outline the latest synthetic strategies of heterostructured MOF-on-MOFs and their derivatives, including ordered epitaxial growth, random epitaxial growth, etc., which show the tutorial guidelines for the further development of various MOF-on-MOFs.
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In order to reduce the high polarization caused by the hysteresis effect of O2 diffusion and boost the power density of oxygen cathodes under a transient heavy load, an Al-MOF-derived porous carbon-modified Pt/C catalyst is proposed as a new capacitive ORR catalyst to construct super fuel cells (SFCs) via an ORR + EDLC dual-discharge parallel process. Herein, a capacitive porous carbon material (BTCC-2) with a large specific surface area (SSA) and high graphitization was synthesized via one-step carbonization of Al-MOFs (Al-BTC). After compounding BTCC-2 with commercial Pt/C catalysts, electrochemical tests were performed and revealed that the composite with 40% BTCC-2 provided the highest transient discharge performance. Moreover, the composite had a higher onset potential and limiting current density (5.236 mA cm-2) than Pt/C and a half-wave potential (0.833 V) comparable to that of Pt/C. The abundant pore structure and large surface of BTCC-2 greatly increased the interaction between oxygen and the catalyst surface. Besides, the contained BTCC-2 serve as a significant power bank to remarkably buffer and relieve the rapidly decreasing output voltage under an instant heavy load owing to the oxygen deficiencies in a Zn-air battery through the ORR + EDLC dual-parallel-discharge process. The proposed SFC design has potential as a universal method to solve the sluggish ORR process and provide high transient power density for fuel cell-driven vehicles.
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The use of a methanesulfonic acid (MSA) electrolytic system is recommended as a green method for hydrometallurgical recovery of metallic Pb from waste lead-acid batteries (LABs), contributing to the sustainable protection of the ecosystem. Nevertheless, the system's high energy consumption is a current issue due to the substantial overpotential of the oxygen evolution reaction (OER) and competitive anodic oxidation of Pb2+. Herein, we propose an IrFe/nitrogen-doped pyrolytic carbon black (IrFe/NCBp) composite as a novel OER catalyst for the MSA electrolytic system, which demonstrates advanced OER catalytic efficiency and selectivity for H2O oxidation. This can be ascribed to the catalyst's thoughtful design, which enhances the number and uniformity of Ir and Fe species via increasing the specific surface area and employing NCBp as a sustainable substrate. The optimized IrFe/NCBp composite exhibits superior OER performance, with a low 252 mV@10 mA cm-2 overpotential and a 62 mV dec-1 Tafel slope, and excellent durability in a 1 M MSA electrolyte for 30 h operation compared to commercial Ir/C. In contrast to carbon paper (CP) and commercial Ir/C anodes, the anodic reaction of IrFe/NCBp is primarily OER-driven (97%) in 1 M MSA and 0.2 M Pb2+ electrolyte for Pb recovery. This effectively circumvents the high potential oxidation of Pb2+ into PbO2, reducing the electrolytic voltage to 488 kWh for the recovery of 1 ton Pb metal. This work provides a green, low-carbon footprint solution for the MSA electrolytic system, thereby promoting the commercialization of the hydrometallurgical Pb recovery.
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The direct recovery of high-purity PbO from spent lead paste without a pre-desulfation process has significant industrial promise. Herein, we propose a recyclable, ultra-fast, and high value-added closed-loop of high-purity PbO recovery process by intensive multidentate coordination of histidine with crude 2PbO·PbSO4 by a rotating liquid-film (RLF) reactor and CO2 carbonation-dissociation. Parameter optimizations and kinetic calculations show the leaching time is shortened from 40 min to 60 s with 99.14 % leaching rate and 99.99 % PbO purity by internal diffusion control, where the RLF reactor promotes mass transfer and reaction rates by instantly renewing the surface of crude 2PbO·PbSO4. Furthermore, all 5 batches reveal that the separation of SO42- ions from the regenerated mother liquid with Ba(OH)2 significantly improves the recycling rate of the mother liquid and high-purity PbO product. This new strategy reveals a bright prospect of a highly efficient, high value-added, and environmentally friendly recycling route for solid waste resources.
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Suministros de Energía Eléctrica , Plomo , Óxidos , Reciclaje , Reciclaje/métodos , Plomo/química , Óxidos/química , Administración de Residuos/métodos , CinéticaRESUMEN
Rechargeable aqueous zinc-ion batteries have attracted a lot of attention owing to their cost effectiveness and plentiful resources, but less research has been conducted on the aspect of high volumetric energy density, which is crucial to the space available for the batteries in practical applications. In this work, highly crystalline V2O5 microspheres were self-assembled from one-dimensional V2O5 nanorod structures by a template-free solvothermal method, which were used as cathode materials for zinc-ion batteries with high performance, enabling fast ion transport, outstanding cycle stability and excellent rate capability, as well as a significant increase in tap density. Specifically, the V2O5 microspheres achieve a reversible specific capacity of 414.7 mAh g-1 at 0.1 A g-1, and show a long-term cycling stability retaining 76.5% after 3000 cycles at 2 A g-1. This work provides an efficient route for the synthesis of three-dimensional materials with stable structures, excellent electrochemical performance and high tap density.
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Pursuing high power density with low platinum catalysts loading is a huge challenge for developing high-performance fuel cells (FCs). Herein, a new super fuel cell (SFC) is proposed with ultrahigh output power via specific electric double-layer capacitance (EDLC) + oxygen reduction reaction (ORR) parallel discharge, which is achieved using the newly prepared catalyst, single-atomic platinum on bimetallic metal-organic framework (MOF)-derived hollow porous carbon nanorods (PtSA /HPCNR). The PtSA-1.74 /HPCNR-based SFC has a 3.4-time higher transient specific power density and 13.3-time longer discharge time with unique in situ self-charge and energy storage ability than 20% Pt/C-based FCs. X-ray absorption fine structure, aberration-corrected high-angle annular dark-field scanning transmission electron microscope, and density functional theory calculations demonstrate that the synergistic effect of Pt single-atoms anchored on carbon defects significantly boosts its electron transfer, ORR catalytic activity, durability, and rate performance, realizing rapid " ORR+EDLC" parallel discharge mechanism to overcome the sluggish ORR process of traditional FCs. The promising SFC leads to a new pathway to boost the power density of FCs with extra-low Pt loading.
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Nickel-iron-layered double hydroxide (NiFeLDH) is one of the promising catalysts for the oxygen evolution reaction (OER) in alkaline electrolytes, but its conductivity limits its large-scale application. The focus of current work is to explore low-cost, conductive substrates for large-scale production and combine them with NiFeLDH to improve its conductivity. In this work, purified and activated pyrolytic carbon black (CBp) is combined with NiFeLDH to form an NiFeLDH/A-CBp catalyst for OER. CBp not only improves the conductivity of the catalyst but also greatly reduces the size of NiFeLDH nanosheets to increase the activated surface area. In addition, ascorbic acid (AA) is introduced to enhance the coupling between NiFeLDH and A-CBp, which can be evidenced by the increase of Fe-O-Ni peak intensity in FTIR measurement. Thus, a lower overvoltage of 227 mV and larger active surface area of 43.26 mF·cm-2 are achieved in 1 M KOH solution for NiFeLDH/A-CBp. In addition, NiFeLDH/A-CBp shows good catalytic performance and stability as the anode catalyst for water splitting and Zn electrowinning in alkaline electrolytes. In Zn electrowinning with NiFeLDH/A-CBp, the low cell voltage of 2.08 V at 1000 A·m-2 results in lower energy consumption of 1.78 kW h/KgZn, which is nearly half of the 3.40 kW h/KgZn of industrial electrowinning. This work demonstrates the new application of high-value-added CBp in hydrogen production from electrolytic water and zinc hydrometallurgy to realize the recycling of waste carbon resources and reduce the consumption of fossil resources.
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High-performance rechargeable oxygen electrodes are key devices for realizing high-specific-energy batteries, including zinc-air and lithium-air batteries. However, these batteries have severe problems of premature decay in energy efficiency by serious corrosion, wide charge-discharge gap, and catalyst peeling off. Herein, we propose a "smart dual-oxygen electrode", which is composed of an intelligent switch control module + heterostructured Fe1Ni3-LDH/PNCNF OER catalysis electrode layer + ion conductive | electronic insulating membrane + Pt/C ORR catalysis electrode layer, where OER and ORR layers are automatically switched by the intelligent switch control module as required. This smart dual-oxygen electrode offers an ultralow energy efficiency decay rate of 0.0067% after 300 cycles during cycling, much lower than that of the commercial Pt/C electrode (1.82%). The assembled rechargeable zinc-air battery (RZAB) displays a super narrow voltage gap and achieves a high energy efficiency of 71.7%, far higher than that of the existing RZABs (about 50%). Therefore, this strategy provides a complete solution for designing various high-performance metal-air secondary batteries.
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The new low-cost clean pre-desulfation technology is very important in pyrometallurgy and hydrometallurgy. However, traditional reactors have low space-time yield and desulfation rate, resulting in high energy consumption and SO2 emissions in the industrial desulfation processes. Herein, dual rotating liquid film reactors (RLFRs) and lime are proposed to construct a recyclable, ultra-fast, and value-added desulfation method. Parameter optimization and kinetic calculations prove that the above reactions are controlled by internal diffusion, revealing that RLFR promotes the mass transfer and reaction rate. The new process greatly shortens the desulfation time of lead paste from 40 min to 10 s with a high desulfation rate of 99.7%, and the sulfation time of lime from 30 min to 30 s with a sulfation rate of 98.6% with a net profit of 55.99 ¥/ton by cost accounting. Moreover, ten batches of continuous scale-up experiments demonstrate the stability of processes, the desulfation and sulfation rates are kept at 99.7% and 98.2%, which greatly reduces the emissions of waste desulfate liquor. This work provides a new universal strategy for a sustainable, low-cost, and clean desulfation method of waste resources to achieve technical and economic feasibility.
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Aqueous zinc-ion batteries are considered as an ideal substitute for lithium-ion batteries due to their abundant resource storage, high safety, and low price. However, zinc anodes exhibit poor reversibility and cyclic stability in most conventional aqueous electrolytes. Herein, an environmentally friendly Zn(CH3SO3)2 electrolyte is proposed to solve the problems of common aqueous electrolytes. The bulky CH3SO3- anions can regulate the solvation structure of Zn2+ by replacing some water molecules in the primary solvation sheath of Zn2+, thus slowing the hydrogen evolution side reactions and formation of zinc dendrite. Additionally, the changing solvation structure weakens the bonding between Zn2+ and the surrounding water molecules, which is conducive to the transport and charge transfer of Zn2+, thus improving the battery capacity. In the Zn(CH3SO3)2 electrolyte, Zn plating/stripping exhibits a high Coulombic efficiency of >98% and long-term cyclic stability over 800 h. The specific capacity of the assembled Zn//V2O5 cell in 3 mol L-1 Zn(CH3SO3)2 reaches 350 mA h g-1 at 0.1 A g-1, much higher than that in the ZnSO4 electrolyte (213 mA h g-1). In conclusion, this work offers insights into the exploration of advanced green electrolyte systems for zinc-ion batteries.
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In this paper, a new hexagonal prismatic Zn-MOF is rapidly synthesized at room temperature through a one-step precipitation method as precursor for the preparation of porous carbon. The SEM and GCD tests indicate that the pre-ionization process of BTC greatly accelerates the reaction speed between BTC and Zn ions, and only 0.5 h is required for the preparation of Zn-MOF with orderly morphology at room temperature, far less than 3-24 h of the existing hydrothermal synthesis. The derived porous carbon (BTCC) is provided with a considerable specific surface area of 1,464 m2 g-1 and suitable pores of 3.9 nm in size. Its richly porous structure offers a superior supercapacitor performance. The BTCC electrode offered a high specific capacitance and an excellent cycle stability. Furthermore, the assembled two symmetrical supercapacitors, C|1 M Na2SO4|C and C|6 M KOH|C, provide high energy density of 22.4 Wh kg-1 and 13.7 Wh kg-1, respectively. Their energy retention rates were 80.0% and 89.4%, respectively after 10,000 cycles at 20 A g-1. The proposed pre-ionization strategy is a facile, convenient and easy-to-industrial method for the preparation of new MOFs, thereby significantly reducing the manufacturing cost of porous carbon for energy storage.
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Metal organic frameworks (MOFs) and their derivatives have been widely used in electrochemistry due to their adjustable pore size and high specific surface area (SSA). Herein, a spindle-like hierarchical porous activated carbon (SPC) was synthesized through carbonizing the Al-BTEC precursor and then alkaline washing with NaOH. The fabricated SPC has a uniform shuttle-shaped structure, showing a large BET surface area of 1895 m2 g-1 and an average pore size of 2.4 nm. The SPC product displays a high specific capacitance (SC) of 337 F g-1 at 1 mV s-1 and 334 F g-1 at 1 A g-1. The retention of SC is about 95% after 100 000 cycles when the current density is 50 A g-1, indicating its excellent stability. Furthermore, the assembled symmetrical capacitor with a two-electrode system exhibits a high SC of 173 F g-1 at 1 A g-1 and an energy density of 15.3 W h kg-1 at a power density of 336 W kg-1. This work would provide a new pathway to design and synthesize carbon materials for supercapacitors with excellent properties in the future.
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Hollow carbon materials are regarded as crucial support materials in catalysis and electrochemical energy storage on account of their unique porous structure and electrical properties. Herein, an indium-based organic framework of InOF-1 can be thermally carbonized under inert argon to form indium particles through the redox reaction between nanosized indium oxide and carbon matrix. In particular, a type of porous hollow carbon nanostraw (HCNS) is in situ obtained by combining the fusion and removal of indium within the decarboxylation process. The as-synthesized HCNS, which possesses more charge active sites, short and quick electron, and ion transport pathways, has become an excellent carrier for electrochemically active species such as iodine with its unique internal cavity and interconnected porous structure on the tube wall. Furthermore, the assembled zinc-iodine batteries (ZIBs) provide a high capacity of 234.1 mAh g-1 at 1 A g-1 , which ensures that the adsorption and dissolution of iodine species in the electrolyte reach a rapid equilibrium. The rate and cycle performance of the HCNS-based ZIBs are greatly improved, thereby exhibiting an excellent capacity retention rate. It shows a better electrochemical exchange capacity than typical unidirectional carbon nanotubes, making HCNS an ideal cathode material for a new generation of high-performance batteries.
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BACKGROUND: Chronic non-bacterial prostatitis (CNBP) accounts for more than 90 % of clinical prostatitis cases, and there is no specific and effective treatment for CNBP. The regulatory role of Jiedu Huoxue decoction (JDHXD)in CNBP remains unclear. We investigated if JDHXD could improve CNBP METHODS: The animal model of CNBP was established by carrageenan injection with 1 % carrageenan (50 µL). The prostate index, epithelial thickness, lumen area, and pain response time were investigated. The apoptosis levels were measured with TUNEL staining and flow cytometry, respectively. Inflammatory factors in the serum were measured with ELISA method. RESULTS: Treatment with JDHXD significantly improve prostate tissues injury in CNBP rats. Some parameters, such as prostate index, and pain response time, reflecting the prostate function were improved by JDHXD. Inhibition of apoptosis, reactive oxygen species (ROS), and inflammatory response were achieved by JDHXD in vivo. JDHXD markedly suppressed the TGF-ß/SMAD signaling pathway, and activation of TGF-ß/SMAD signaling pathway could reverse the improvement of CNBP injury by JDHXD. The anti-inflammatory, anti-oxidative and anti-apoptotic effects of JDHXD were proved. CONCLUSION: JDHXD might improve CNBP injury through suppressing inflammation response, ROS, and apoptosis by targeting TGF-ß/SMAD signaling pathway. This research might provide a new thought for the prevention and treatment of CNBP through inhibiting TGF-ß/SMAD signaling pathway.
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Prostatitis , Animales , Carragenina/farmacología , Humanos , Masculino , Dolor , Prostatitis/tratamiento farmacológico , Prostatitis/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
Metal-organic framework (MOF) derived porous carbon materials have been widely applied as active materials for supercapacitors due to their large specific surface area and ordered pore structure. This paper presents a facile and effective strategy to regulate the morphology of a zinc-based metal-organic framework (Zn-trimesic acid, Zn-BTC) by adjusting the ethanol content in a solvent, which can effectively change the pore structure of Zn-BTC derived porous carbon (PC). The optimal PC prepared in 50% ethanol displays a rodlike structure with a large specific surface area (SSA) of 1930 m2 g-1 and an average pore size of 2.9 nm. This material shows an excellent rate performance with 78.8% capacitance retention when the current density increases from 1 A g-1 to 100 A g-1 and outstanding electrochemical stability with only 2.2% decline of capacitance after 200 000 cycles at 50 A g-1. Moreover, the assembled symmetrical capacitor shows a high energy density of 16.09 W h kg-1 at 698 W kg-1 and 11.89 W h kg-1 at a high power density of 41.56 kW kg-1. This method would provide a new pathway for the preparation of carbon materials with an adjustable pore size for high-performance supercapacitors.
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BACKGROUND: Chronic abacterial prostatitis/chronic pelvic pain syndrome (CP/CPPS) accounts for 90% of clinical prostatitis, and there is no specific and effective treatment for it. Jiedu Huoxue decoction (JDHXD) has been believed to be an effective agent for CP/CPPS, but the specific mechanism remains unclear. METHODS: Carrageenan and LPS were used to established the animal and cell models of CP/CPPS, respectively. The prostate index, urine volume, lumen area, epithelial thickness, and pain response time were investigated. TUNEL staining and flow cytometry were applied to measure apoptosis levels in vivo and in vitro. RESULTS: JDHXD improved CP/CPPS recovery in a dose-dependent manner. JDHXD restrained apoptosis and activated Wnt/GSK-3ß/ß-catenin signaling pathway in the CP/CPPS animal model. Inhibition of Wnt/GSK-3ß/ß-catenin signaling pathway remarkably aggravated apoptosis and suppressed the improvement of CP/CPPS by JDHXD. XAX939 markedly reversed the suppression of cell apoptosis and ROS level caused by JDHXD in vitro. CONCLUSION: Jiedu Huoxue decoction improved CP/CPPS through activating Wnt/GSKß/ß-catenin signaling pathway and inhibiting apoptosis. This study might provide a novel insight for the prevention and treatment of CP/CPPS through activating Wnt/GSK-3ß/ß-catenin signaling pathway.
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Dolor Crónico , Prostatitis , Animales , Apoptosis , Enfermedad Crónica , Dolor Crónico/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Masculino , Dolor Pélvico/tratamiento farmacológico , Dolor Pélvico/metabolismo , Prostatitis/tratamiento farmacológico , Prostatitis/metabolismo , Ratas , Ratas Sprague-Dawley , Síndrome , Vía de Señalización Wnt , beta Catenina/metabolismoRESUMEN
The quiescent electrolyte causes serious concentration polarization and dendrite problems during the charging and discharging of the battery, which restricts the development of metal secondary batteries and flow batteries. Herein, we report a new concept of ion motors, with which the directional driving and uniformity of the electrolyte are realized to eliminate the concentration polarization and dendritic phenomenon for secondary metal batteries and flow batteries without additional external energy. In this study, a dendrite-free secondary metal battery with ion motors is constructed to eliminate a considerable concentration polarization voltage by a tiny induced counter electromotive force generated by Lorentz force, significantly improving the output power and energy efficiency of the battery. An actual pump-free flow battery with an ion motor is also assembled, which overcomes the problems of low energy efficiency and the complex structure caused by the traditional flow battery requiring 1-2 pumps to drive the electrolyte. The efficiency of ion motors to drive the electrolyte is hundreds of times higher than that of the mechanical pump. Therefore, the ion motor provides a universal strategy for designing more pump-free flow batteries and metal secondary batteries without the risk of dendrites in the future.
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BACKGROUND: Venous leg ulcers (VLUs) are the most common ulcer on the lower extremity, with 4% of patients over the age of 65 suffering from VLUs worldwide. As a recurrent, chronic, disabling disease, VLUs are associated with prolonged disability, substantial socioeconomic impact, and significant psychosocial morbidity. At present, Skin grating is one of the most effective treatments for non-healing ulcers. However, there are still no new studies based on the latest research and new research methods to evaluate and compare the effect of different types of skin grafts for treating venous leg ulcers. Therefore, a Bayesian network meta-analysis (NMA) will be conducted to systematically assess skin grafting efficacy for VLUs. METHODS: We will include randomized controlled trials (RCTs) involving patients with VLUs treated by skin grafts. Electronic databases and clinical trials registries will be searched from their inception until June 2021, without language or publication restrictions on status. The search strategy mainly includes Medical Subject Headings (MeSH) and free-text terms. Two review authors will independently perform data extraction and assessment of study quality. And We will use Bayesian NMA to evaluate all available evidence in STATA 14.0 and WinBUGS software. RESULTS: This protocol will use Bayesian NMA to assess the effectiveness of different types of skin grafting for treating venous leg ulcers. CONCLUSION: This study aims to synthesize the available evidence from RCTs in a network meta-analysis to summarize the best research available and provide consistency among treatment protocols given to patients, resulting in improved efficacy and the quality of care and reduced cost.