Li metal is one of the most promising anode materials for high energy density batteries. However, uncontrollable Li dendrite growth and infinite volume change during the charge/discharge process lead ...to safety issues and capacity decay. Herein, a carbonized metal–organic framework (MOF) nanorod arrays modified carbon cloth (NRA‐CC) is developed for uniform Li plating/stripping. The carbonized MOF NRAs effectively convert the CC from lithiophobic to lithiophilic, decreasing the polarization and ensuring homogenous Li nucleation. The 3D interconnected hierarchal CC provides adequate Li nucleation sites for reducing the local current density to avoid Li dendrite growth, and broadens internal space for buffering the volume change during Li plating/stripping. These characteristics afford a stable cycling of the NRA‐CC electrode with ultrahigh Coulombic efficiencies of 96.7% after 1000 h cycling at 2 mA cm−2 and a prolonged lifespan of 200 h in the symmetrical cell under ultrahigh areal capacity (12 mAh cm−2) and current (12 mA cm−2). The solid‐state batteries assembled with the composite Li anode, high‐voltage cathode (LiNi0.5Co0.2Mn0.3O2), and composite solid‐state electrolyte also deliver excellent cyclic and rate performance at 25 °C. This work sheds fresh insights on the design principles of a dendrite‐free Li metal anode for safe solid‐state Li metal batteries.
Dendrite‐free Li anodes can be achieved through a carbonized Co‐based zeolitic imidazolate framework nanorod arrays modified carbon cloth (NRA‐CC). Owing to the synergistic effect of the interconnected carbon cloth and lithiophilic Co–N–C NRAs, NRA‐CC can regulate the Li plating/stripping behavior and withstand high areal capacity and current density. The composite Li anode is successfully applied in solid‐state Li metal batteries.
Lithium metal anodes show immense scope for application in high‐energy electronics and electric vehicles. Unfortunately, lithium dendrite growth and volume change leading to short lifespan and safety ...issues severely limit the feasibility of lithium metal batteries. A rational design of metal–organic framework (MOF)‐modified Li metal anode with optimized Li plating/stripping behavior via one‐step carbonization of ZIF‐67 is proposed. Experimental and theoretical simulation results reveal that carbonized MOFs with uniformly dispersed Co nanoparticles in N‐graphene (Co@N‐G) exhibit an electronic/ionic dual‐conductivity and significantly improved affinity with Li, and so serve as an ideal host for dendrite‐free lithium deposition, consequently leading to uniform lithium plating/stripping during cycling. As a result, the anode delivers highly stable cyclic performance with high coulombic efficiency (CE) at ultrahigh current densities (CE = 91.5% after 130 cycles at 10 mA cm−2, and CE = 90.4% after 80 cycles at 15 mA cm−2). Moreover, the practical applicability and functionality of such anodes are demonstrated through assembly of Li‐Co@N‐G/NCM full batteries exhibiting a long cycle life of 100 cycles with a high capacity retention of 92% at 1 C.
High‐rate dendrite‐free lithium anodes can be achieved through Co‐embedded N‐doped graphene (Co@N‐G) modification. A rational design for metal–organic‐framework‐modified Li metal anodes is proposed via one‐step carbonization of ZIF‐67. Owing to the improved affinity with Li, electronic/ionic dual‐conductivity, and stable rhombic‐dodecahedron structure, Co@N‐G can decrease Li+ nucleation barriers, regulate Li plating/stripping behavior, and withstand high current densities.
New S in town: Sulfonyl hydrazides smoothly undergo sulfenylation with indoles in the presence of 10 mol % I2 to give structurally diverse indole thioethers in moderate to excellent yields with ...extremely high regioselectivity. This study paves the way for the use of sulfonyl hydrazides as unique sulfur electrophiles in chemical synthesis.
Biochar draws increasing attention as soil amendment, carbon sink, slow-release fertilizer, and adsorbent. Herein, it was interesting to find out that among 11 kinds of commercial biochar, 3 of them ...facilitated ferrate oxidation of sulfamethoxazole (SMX). With the addition of biochar, oxidation rates of 5 kinds of organic pollutants (including antibiotics, pharmaceuticals, and personal care product) increased by 3–14 times, and the total organic carbon (TOC) removal ratio increased by 2.4–8 times. Radical scavenging experiment, electron spin resonance (ESR) analysis, and probe compound (sulfoxide) oxidation experiment showed that no radical but intermediate iron species Fe(IV) and Fe(V) participated in the oxidation reactions. Redox-active moieties (phenolic hydroxyl) on biochar interact with ferrate as electron shuttle and enhance the formation of intermediate iron species through electron transfer. The intermediate iron species not only interacted with organic pollutants and accelerated their transformation, but also corrupted (oxidized) the physical structure of biochar and expanded its surface area and pore volume. Increase of surface area and pore volume of the spent biochar in turn resulted in the improved adsorption capacity. In addition to eliminating emerging organic pollutants, ferrate/biochar removed 8.7%–31.6% of TOC in authentic water and decreased the formation potential of 20 kinds of chlorinated disinfection by-products (DBPs) by 9.2%–23.9%.
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•Biochar reacted with Fe(VI) with the formation of Fe(IV)/Fe(V).•Fe(IV)/Fe(V) was more reactive with organic pollutants compared with Fe(VI).•Biochar enhanced Fe(VI) oxidation of SMX, CBZ, CIP, DCF, and DEET.•Fe(IV)/Fe(V) corrupted structure of biochar and facilitated the adsorption of TOC.
Molecular descriptors are widely employed to present molecular characteristics in cheminformatics. Various molecular-descriptor-calculation software programs have been developed. However, users of ...those programs must contend with several issues, including software bugs, insufficient update frequencies, and software licensing constraints. To address these issues, we propose Mordred, a developed descriptor-calculation software application that can calculate more than 1800 two- and three-dimensional descriptors. It is freely available via GitHub. Mordred can be easily installed and used in the command line interface, as a web application, or as a high-flexibility Python package on all major platforms (Windows, Linux, and macOS). Performance benchmark results show that Mordred is at least twice as fast as the well-known PaDEL-Descriptor and it can calculate descriptors for large molecules, which cannot be accomplished by other software. Owing to its good performance, convenience, number of descriptors, and a lax licensing constraint, Mordred is a promising choice of molecular descriptor calculation software that can be utilized for cheminformatics studies, such as those on quantitative structure–property relationships.
•MnOx/biochar and FeOx/biochar significantly improved ozonization of ATZ.•Enhanced formation of •OH was observed in the catalytic ozonation systems.•Increased Lewis acid sites and electron transfer ...contributed for the O3 catalyzation.•Toxicity of ATZ had been largely eliminated after the heterogeneous catalytic ozonation.
After reaction with permanganate or ferrate, the resulted Mn-loaded and Fe-loaded biochar (MnOx/biochar and FeOx/biochar) exhibited excellent catalytic ozonation activity. O3 (2.5 mg/L) eliminated 48% of atrazine (ATZ, 5 μM) within 30 min at pH 7.0, while under identical conditions, ozonation efficiency of ATZ increased to 83% and 100% in MnOx/biochar and FeOx/biochar (20 mg/L) heterogeneous catalytic systems, respectively. Radical scavenger experiment and electron paramagnetic resonance (EPR) analysis confirmed that hydroxyl radical (•OH) was the dominant oxidant. Total Lewis acid sites on MnOx/biochar and FeOx/biochar were 3.5 and 4.1 times of that on the raw biochar, which induced enhanced adsorption of O3 and its subsequent decomposition into •OH. Electron transfer via redox pairs on MnOx/biochar and FeOx/biochar was observed by cyclic voltammetry scans, which also functioned in the improved catalytic capacity. Degradation pathways of ATZ in MnOx/biochar and FeOx/biochar ozonation systems were proposed, with 34.6% and 44.8% of dechlorination effect accomplished within 30 min of reaction, which was improved by 4.1 and 5.3 times compared to pure ozonation. After 12-hour treatment, acute toxicity of ATZ oxidation products was reduced from 38.3% of pure ozonation system to 14.5% and 6.3% of activated ozonation systems with MnOx/biochar and FeOx/biochar, respectively. Mn-loaded biochar and Fe-loaded biochar have great potential for heterogeneous catalytic ozonation of polluted water.
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Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has ...been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.
Various types of urban art emerged and prospered in recent decades when degenerating cities were embracing art as a marketing strategy. This urban- rejuvenation approach sheds less light on the ...agency and motivation of artists. This paper examines how ethnic artists represent traumatic memory, reflect nostalgia, and mobilize individuals to collaborate with one another to build resilience. This study contributes to the literature that explores the agency and creativity of underrepresented ethnic minority artists in a global society at large.
The global occurrence of viral infectious diseases poses a significant threat to human health. Dengue virus (DENV) infection is one of the most noteworthy of these infections. According to a WHO ...survey, approximately 400 million people are infected annually; symptoms deteriorate in approximately one percent of cases. Numerous foundational and clinical investigations on viral epidemiology, structure and function analysis, infection source and route, therapeutic targets, vaccines, and therapeutic drugs have been conducted by both academic and industrial researchers. At present, CYD-TDV or Dengvaxia® is the only approved vaccine, but potent inhibitors are currently under development. In this review, an overview of the viral life circle and the history of DENVs is presented, and the most recently reported antiviral candidates and newly discovered promising targets are focused and summarized. We believe that these successes and failures have enabled progress in anti-DENV drug discovery and hope that our review will stimulate further innovation in this area.
Step by step: Highly selective cross dehydrogenative arylation of acetanilides was developed to construct biaryls under mild condition. With this method, different aryl CH bonds were activated in ...sequential reactions to construct functionalized carbazoles (see scheme), which are present as key structural units in various biological molecules and organic optical materials.
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