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Perception of UV radiation has important applications in medical health, industrial production, electronic communication, etc. In numerous application scenarios, there is an increasing demand for the intuitive and low-cost detection of UV radiation through colorimetric visual behavior, as well as the efficient and multi-functional utilization of UV radiation. However, photodetectors based on photoconductive modes or photosensitive colorimetric materials are not conducive to portable or multi-scene applications owing to their complex and expensive photosensitive components, potential photobleaching, and single-stimulus response behavior. Here, a multifunctional visual sensor based on the "host-guest photo-controlled permutation" strategy and the "lock and key" model is developed. The host-guest specific molecular recognition and electrochromic sensing platform is integrated at the micro-molecular scale, enabling multi-functional and multi-scene applications in the convenient and fast perception of UV radiation, military camouflage, and information erasure at the macro level of human-computer interaction through light-electrical co-controlled visual switching characteristics. This light-electrical co-controlled visual sensor based on an optoelectronic multi-mode sensing system is expected to provide new ideas and paradigms for healthcare, microelectronics manufacturing, and wearable electronic devices owing to its advantages of signal visualization, low energy consumption, low cost, and versatility.
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Single-atom catalysts exhibit promising electrocatalytic activity, a trait that can be further enhanced through the introduction of heteroatom doping within the carbon skeleton. Nonetheless, the intricate relationship between the doping positions and activity remains incompletely elucidated. This contribution sheds light on an inductive effect of single-atom sites, showcasing that the activity of the oxygen reduction reaction (ORR) can be augmented by reducing the spatial gap between the doped heteroatom and the single-atom sites. Drawing inspiration from this inductive effect, we propose a synthesis strategy involving ligand modification aimed at precisely adjusting the distance between dopants and single-atom sites. This precise synthesis leads to optimized electrocatalytic activity for the ORR. The resultant electrocatalyst, characterized by Fe-N3P1 single-atom sites, demonstrates remarkable ORR activity, thus exhibiting great potential in zinc-air batteries and fuel cells.
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Coordination engineering for single-atom sites has drawn increasing attention, yet its chemical synthesis remains a tough issue, especially for tailorable coordination structures. Herein, a molecular recognition strategy is proposed to fabricate single-atom sites with regulable local coordination structures. Specifically, a heteroatom-containing ligand serves as the guest molecule to induce coordination interaction with the metal-containing host, precisely settling the heteroatoms into the local structure of single-atom sites. As a proof of concept, thiophene is selected as the guest molecule, and sulfur atoms are successfully introduced into the local coordination structure of iron single-atom sites. Ultrahigh oxygen reduction electrocatalytic activity is achieved with a half-wave potential of 0.93â V versus reversible hydrogen electrode. Furthermore, the strategy possesses excellent universality towards diversified types of single-atom sites. This work makes breakthroughs in the fabrication of single-atom sites and affords new opportunities in structural regulation at the atomic level.
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Oxygen reduction and evolution reactions constitute the core process of many vital energy storage or conversion techniques. However, the kinetic sluggishness of the oxygen redox reactions and heavy reliance on noble-metal-based electrocatalysts strongly limit the energy efficiency of the related devices. Developing high-performance noble-metal-free bifunctional ORR and OER electrocatalysts has gained worldwide attention, where much important progress has been made during the last decade. This review systematically addresses the design principles to obtain high-performance noble-metal-free bifunctional oxygen electrocatalysts by emphasizing strategies of both intrinsic activity regulation and active site integration. A statistical analysis of the reported bifunctional electrocatalysts is further carried out to reveal the composition-performance relationship and guide further exploration of emerging candidates. Finally, perspectives for developing advanced bifunctional oxygen electrocatalysts and aqueous rechargeable metal-air batteries are proposed.
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Aqueous zinc-air batteries possess inherent safety and are especially commendable facing high-temperature working conditions. However, their working feasibility at high temperatures has seldom been investigated. Herein, the working feasibility of high-temperature zinc-air batteries is systemically investigated. The effects of temperature on air cathode, zinc anode, and aqueous electrolyte are decoupled to identify the favorable and unfavorable factors. Specifically, parasitic hydrogen evolution reaction strengthens at high temperatures and leads to declined anode Faraday efficiency, which is identified as the main bottleneck. Moreover, zinc-air batteries demonstrate cycling feasibility at 80 °C. This work reveals the potential of zinc-air batteries to satisfy energy storage at high temperatures and guides further development of advanced batteries towards harsh working conditions.
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Lithium-sulfur (Li-S) batteries constitute promising next-generation energy storage devices due to the ultrahigh theoretical energy density of 2600 Wh kg-1. However, the multiphase sulfur redox reactions with sophisticated homogeneous and heterogeneous electrochemical processes are sluggish in kinetics, thus requiring targeted and high-efficient electrocatalysts. Herein, a semi-immobilized molecular electrocatalyst is designed to tailor the characters of the sulfur redox reactions in working Li-S batteries. Specifically, porphyrin active sites are covalently grafted onto conductive and flexible polypyrrole linkers on graphene current collectors. The electrocatalyst with the semi-immobilized active sites exhibits homogeneous and heterogeneous functions simultaneously, performing enhanced redox kinetics and a regulated phase transition mode. The efficiency of the semi-immobilizing strategy is further verified in practical Li-S batteries that realize superior rate performances and long lifespan as well as a 343 Wh kg-1 high-energy-density Li-S pouch cell. This contribution not only proposes an efficient semi-immobilizing electrocatalyst design strategy to promote the Li-S battery performances but also inspires electrocatalyst development facing analogous multiphase electrochemical energy processes.
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Single-atom catalysts (SACs) with highly active sites atomically dispersed on substrates exhibit unique advantages regarding maximum atomic efficiency, abundant chemical structures, and extraordinary catalytic performances for multiple important reactions. In particular, M-N-C SACs (M=transition metal atom) demonstrate optimal electrocatalytic activity for the oxygen reduction reaction (ORR) and have attracted extensive attention recently. Despite substantial efforts in fabricating various M-N-C SACs, the principles for regulating the intrinsic electrocatalytic activity of their active sites have not been sufficiently studied. In this Review, we summarize the regulation strategies for promoting the intrinsic electrocatalytic ORR activity of M-N-C SACs by modulation of the center metal atoms, the coordinated atoms, the environmental atoms, and the guest groups. Theoretical calculations and experimental investigations are both included to afford a comprehensive understanding of the structure-performance relationship. Finally, future directions of developing advanced M-N-C SACs for electrocatalytic ORR and other analogous reactions are proposed.
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Efficient energy storage at low temperatures starves for competent battery techniques. Herein, inherent advantages of zinc-air batteries on low-temperature electrochemical energy storage are discovered. The electrode reactions are resistive against low temperatures to render feasible working zinc-air batteries under sub-zero temperatures. The relatively reduced ionic conductivity of electrolyte is identified as the main limiting factor, which can be addressed by employing a CsOH-based electrolyte through regulating the solvation structures. Accordingly, 500â cycles with a stable voltage gap of 0.8â V at 5.0â mA cm-2 is achieved at -10 °C. This work reveals the promising potential of zinc-air batteries for low-temperature electrochemical energy storage and inspires advanced battery systems under extreme working conditions.
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Single-atom catalysts (SACs) have great potential in electrocatalysis. Their performance can be rationally optimized by tailoring the metal atoms, adjacent coordinative dopants, and metal loading. However, doing so is still a great challenge because of the limited synthesis approach and insufficient understanding of the structure-property relationships. Herein, we report a new kind of Mo SAC with a unique O,S coordination and a high metal loading over 10â wt %. The isolation and local environment was identified by high-angle annular dark-field scanning transmission electron microscopy and extended X-ray absorption fine structure. The SACs catalyze the oxygen reduction reaction (ORR) via a 2 e- pathway with a high H2 O2 selectivity of over 95 % in 0.10 m KOH. The critical role of the Mo single atoms and the coordination structure was revealed by both electrochemical tests and theoretical calculations.
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Gastric cancer (GC) is a common heterogeneous disease. The critical roles of microRNA-340 (miR-340) in the development and progression of GC were emphasized in accumulating studies. This study aims to examine the regulatory mechanism of miR-340 in GC cellular processes. Initially, microarray technology was used to identify differentially expressed genes and regulatory miRs in GC. After that, the potential role of miR-340 in GC was determined via ectopic expression, depletion, and reporter assay experiments. Expression of secreted phosphoprotein 1 (SPP1), miR-340, phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway, and epithelial-mesenchymal transition (EMT)-related genes was measured. Moreover, to further explore the function of miR-340 in vivo and in vitro, proliferation, apoptosis, migration, invasion, and tumorigenic capacity were evaluated. SPP1 was a target gene of miR-340 which could then mediate the PI3K/AKT signaling pathway by targeting SPP1 in GC. Furthermore, miR-340 levels were reduced and SPP1 was enriched in GC tissues and cells, with the PI3K/AKT signaling pathway being activated. Inhibitory effects of upregulated miR-340 on SPP1 and the PI3K/AKT signaling pathway were confirmed in vivo and in vitro. Overexpression of miR-340 or the silencing of SPP1 inhibited GC cell proliferation, invasion, migration, and EMT process, but promoted apoptosis of GC cells. Typically, targeting of SPP1 by miR-340 may contribute to the inhibition of proliferation, migration, invasion, and EMT of GC cells via suppression of PI3K/AKT signaling pathway.
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Transição Epitelial-Mesenquimal , MicroRNAs/metabolismo , Osteopontina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Apoptose/genética , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Camundongos Nus , MicroRNAs/genética , Modelos Biológicos , Invasividade Neoplásica , Osteopontina/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima/genéticaRESUMO
The apoptosis of myoblast in response to excessive cyclic stretch is crucial in adaptive construction of skeletal muscles in orthopedic functional therapy. Mitochondria signaling pathway is the central links in the execution of the intrinsic apoptotic cascade, but its molecular mechanism in stretch-induced apoptosis in myoblasts remains incompletely understood. The aim of this study was to investigate the mechanobiological roles of caspase-9 and Apoptosis Inducing Factor (AIF), two important components in mitochondrial pathway, in stretch-induced apoptosis of myoblast. Hoechst 33258 was used to observe apoptotic cells morphologically and flow cytometry to analyze apoptosis rate of myoblasts. Protein and mRNA of caspase-9 and AIF were detected by Western blotting and RT-PCR. Furthermore, caspase-9 specific inhibitor z-LEHD-fmk was applied to clear the mechanism of caspase-9 pathway in stretch-induced apoptosis. We found that apoptotic rate induced by cyclic stretch increased in a time-dependent manner, and the same tendency of mRNA and protein of caspase-9 and AIF. Caspase-9 inhibition reduced stretch-induced apoptosis, but had no effect on expression of AIF. We concluded that caspase-9 and AIF played an important role in stretch-induced apoptosis in myoblast, and AIF was involved in the process in a caspase-9 independent way. J. Cell. Biochem. 118: 829-838, 2017. © 2016 Wiley Periodicals, Inc.
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Fator de Indução de Apoptose/metabolismo , Apoptose/fisiologia , Caspase 9/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Fator de Indução de Apoptose/genética , Caspase 9/genética , Inibidores de Caspase/farmacologia , Linhagem Celular , Mitocôndrias Musculares/metabolismo , Mioblastos/efeitos dos fármacos , Oligopeptídeos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Estresse MecânicoRESUMO
A new magnetic Fe3O4@C@Ag3PO4 nanocomposites photocatalyst with visible light response has been prepared by solvothermal, hydrothermal and precipitation process. The photocatalyst exhibited high photocatalytic activity and stability for the degradation of rhodamine B (RhB). Almost 100% of RhB was photodegraded with the assistance of magnetic Fe3O4@C@Ag3PO4 nanocomposites after 40 min, and the photocatalyst showed no obvious loss of photocatalytic activity after four times of cyclic utilization. Furthermore, the magnetic Fe3O4@C@Ag3PO4 nanocomposites can be separated by external magnetic field. Further study proved that the photogenerated holes were the main active species in the degradation process.
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Background: Distinguishing benign from malignant sub-centimeter solid pulmonary nodules (SSPNs) continues to be challenging in clinical practice. Earlier diagnosis is crucial for improving patient survival and prognosis. This study aimed to investigate the risk factors of malignant SSPNs and establish and validate a prediction model based on computed tomography (CT) characteristics to assist in their early diagnosis. Methods: A total of 261 consecutive participants with 261 SSPNs were retrospectively recruited between January 2012 and July 2023 from National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (Center 1), including 161 malignant lesions and 100 benign lesions. Patients were randomly assigned to the training set (n=183) and validation set (n=78) according to a 7:3 ratio. Malignant nodules were confirmed by pathology; and benign nodules were confirmed by follow-up or pathology. Clinical data and CT features were collected to estimate the independent predictors of malignancy of SSPN with multivariate logistic analysis. A clinical prediction model was subsequently established by logistic regression. Furthermore, an additional 69 consecutive patients with 69 SSPNs from The Fourth Hospital of Hebei Medical University (Center 2) between January 2022 and December 2022 were retrospectively included as an external cohort to validate the predictive efficacy of the model. The performance of the prediction model was assessed by sensitivity, specificity, and the area under the receiver operating characteristic curve. Results: There were 113 (61.7%), 48 (61.5%) and 28 (40.6%) malignant SSPNs in the training, internal and external validation sets, respectively. Multivariate logistic analysis revealed four independent predictors of malignant SSPNs: tumor-lung interface (P=0.002), spiculation (P=0.04), air bronchogram (P=0.047), and invisible at the mediastinal window (P=0.003). The area under the curve (AUC) for the prediction model in the training set was 0.875 [95% confidence interval (CI): 0.818, 0.933]; and the sensitivity and specificity were 94.7% and 68.6%, respectively. The AUCs in the internal and external validation set were (0.781; 95% CI: 0.664, 0.897) and (0.873; 95% CI: 0.791, 0.955), respectively; the sensitivity and specificity were 66.7% and 83.3% for the internal validation data, and 100.0% and 61.0% for the external validation data, respectively. Conclusions: The prediction model based on CT characteristics could be helpful for distinguishing malignant SSPNs from benign ones.
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BACKGROUND: Currently, there is increasing evidence from clinic, epidemiology, as well as neuroimaging, demonstrating neuropsychiatric abnormalities in COVID-19, however, whether there were associations between brain changes caused by COVID-19 and genetic susceptibility of psychiatric disorders was still unknown. METHODS: In this study, we performed a meta-analysis to investigate these associations by combing single-cell RNA sequencing datasets of brain tissues of COVID-19 and genome-wide association study summary statistics of psychiatric disorders. RESULTS: The analysis demonstrated that among ten psychiatric disorders, gene expression perturbations implicated by COVID-19 in excitatory neurons of choroid plexus were significantly associated with schizophrenia. CONCLUSIONS: Our analysis might provide insights for the underlying mechanism of the psychiatric consequence of COVID-19.
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COVID-19 , Transtornos Mentais , Humanos , Estudo de Associação Genômica Ampla/métodos , Transtornos Mentais/genética , Predisposição Genética para Doença/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Expressão Gênica , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The aims of this study were to investigate the expression of SOX9 (sex determining region Y [SRY]-related high-mobility group box 9) and carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) in benign, premalignant, and malignant gastric lesions and to explore the association between SOX9 and CEACAM1 in gastric carcinogenesis. SOX9 and CEACAM1 expression was detected in normal gastric mucosa, hyperplastic polyp, intestinal metaplasia, gastric intraepithelial neoplasia, and adenocarcinoma by immunohistochemistry. There was low expression of SOX9 and no CEACAM1 expression in normal gastric mucosa and hyperplastic polyps. Intestinal metaplasia began to express CEACAM1 and showed more membranous staining of CEACAM1 than normal mucosa and hyperplastic polyps (P = .000), but SOX9 expression had no significant difference, and the coexpression of SOX9 and CEACAM1 ascended; therefore, the difference was significant (P = .000). Gastric intraepithelial neoplasia showed more SOX9 expression, coexpression of SOX9, and CEACAM1 than in intestinal metaplasia (P = .014 and P = .026, respectively). Carcinoma showed more cytoplasmic CEACAM1 (P = .010), more SOX9 expression (P = .001), and more their coexpression (P = .023) than gastric intraepithelial neoplasia. As to the histologic classification, poorly differentiated carcinoma showed more cytoplasmic CEACAM1 than well and moderately differentiated carcinoma (P = .006 and P = .024, respectively). In the Laurén classification, diffuse carcinoma showed more cytoplasmic CEACAM1 than intestinal carcinoma (P = .0035), but the SOX9 expression and their coexpresison showed no difference (P = .065 and P = .074, respectively). With the elevation of SOX9 expression and the changing of CEACAM1 expression patterns, the coexpressions of SOX9 and CEACAM1 were highly elevated from benign proliferative lesions to malignant lesions. Moreover, the SOX9 expression and the coexpression with CEACAM1 were correlated positively (r = 0.310; P = .015). In addition, SOX9 expression was positively correlated with CEACAM1 expression patterns (r = 0.124; P = .032). In addition, CEACAM1 expression patterns and coexpression of SOX9 and CEACAM1 show significant difference between T1 and T2 and T3 and T4 (P = .021 and P = .011, respectively). Accordingly, compared with N0, N2 and N3 showed significant difference in SOX9 expression (P = .018), CEACAM1 expression patterns (P = .010), and their coexpression (P = .010). SOX9 expression significantly increased from nonneoplastic lesions to neoplastic lesions, and CEACAM1 expression patterns markedly changed; their coexpression also showed signally elevated suggesting that SOX9, as a transcriptional regulator, play important roles in the changing of CEACAM1 expression patterns, which might promote the tumor progression.
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Adenocarcinoma/metabolismo , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/metabolismo , Mucosa Gástrica/metabolismo , Lesões Pré-Cancerosas/metabolismo , Fatores de Transcrição SOX9/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/patologia , Transformação Celular Neoplásica/metabolismo , Mucosa Gástrica/patologia , Humanos , Hiperplasia/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Metaplasia/metabolismo , Estadiamento de Neoplasias , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/patologiaRESUMO
Rechargeable zinc-air batteries afford great potential toward next-generation sustainable energy storage. Nevertheless, the oxygen redox reactions at the air cathode are highly sluggish in kinetics to induce poor energy efficiency and limited cycling lifespan. Air cathodes with asymmetric configurations significantly promote the electrocatalytic efficiency of the loaded electrocatalysts, whereas rational synthetic methodology to effectively fabricate asymmetric air cathodes remains insufficient. Herein, a strategy of asymmetric interface preconstruction is proposed to fabricate asymmetric air cathodes for high-performance rechargeable zinc-air batteries. Concretely, the asymmetric interface is preconstructed by introducing immiscible organic-water diphases within the air cathode, at which the electrocatalysts are in situ formed to achieve an asymmetric configuration. The as-fabricated asymmetric air cathodes realize high working rates of 50 mA cm-2 , long cycling stability of 3400 cycles at 10 mA cm-2 , and over 100 cycles under harsh conditions of 25 mA cm-2 and 25 mAh cm-2 . Moreover, the asymmetric interface preconstruction strategy is universal to many electrocatalytic systems and can be easily scaled up. This work provides an effective strategy toward advanced asymmetric air cathodes with high electrocatalytic efficiency and significantly promotes the performance of rechargeable zinc-air batteries.
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Two new stilbenoids, stemobenoids A (1) and B (2), together with three known compounds were obtained from the roots of Stemona tuberosa. The structures of the new compounds were established by extensive spectroscopic analysis, including HRMS, 1D and 2D NMR data. Compounds 1 and 2 displayed potent quinone reductase inducing activity in Hepa 1c1c7 cells.
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Stemonaceae , Estilbenos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Raízes de PlantasRESUMO
Rechargeable zinc-air batteries call for high-performance bifunctional oxygen electrocatalysts. Transition metal single-atom catalysts constitute a promising candidate considering their maximum atom efficiency and high intrinsic activity. However, the fabrication of atomically dispersed transition metal sites is highly challenging, creating a need for for new design strategies and synthesis methods. Here, a clicking confinement strategy is proposed to efficiently predisperse transitional metal atoms in a precursor directed by click chemistry and ensure successful construction of abundant single-atom sites. Concretely, cobalt-coordinated porphyrin units are covalently clicked on the substrate for the confinement of the cobalt atoms and affording a Co-N-C electrocatalyst. The Co-N-C electrocatalyst exhibits impressive bifunctional oxygen electrocatalytic performances with an activity indicator ΔE of 0.79 V. This work extends the approach to prepare transition metal single-atom sites for efficient bifunctional oxygen electrocatalysis and inspires the methodology on precise synthesis of catalytic materials.
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Rechargeable zinc-air batteries constitute promising next-generation energy storage devices due to their intrinsic safety, low cost, and feasibility to realize high cycling current density and long cycling lifespan. Nevertheless, their cathodic reactions involving oxygen reduction and oxygen evolution are highly sluggish in kinetics, requiring high-performance noble-metal-free bifunctional electrocatalysts that exceed the current noble-metal-based benchmarks. Herein, a noble-metal-free bifunctional electrocatalyst is fabricated, which demonstrates ultrahigh bifunctional activity and renders excellent performance in rechargeable zinc-air batteries. Concretely, atomic Co-N-C and NiFe layered double hydroxides (LDHs) are respectively selected as oxygen reduction and evolution active sites and are further rationally integrated to afford the resultant CoNC@LDH composite electrocatalyst. The CoNC@LDH electrocatalyst exhibits remarkable bifunctional activity delivering an indicator ΔE of 0.63 V, far exceeding the noble-metal-based Pt/C+Ir/C benchmark (ΔE = 0.77 V) and most reported electrocatalysts. Correspondingly, ultralong lifespan (over 3600 cycles at 10 mA cm-2 ) and excellent rate performances (cycling current density at 100 mA cm-2 ) are achieved in rechargeable zinc-air batteries. This work highlights the current advances of bifunctional oxygen electrocatalysis and endows high-rate and long-cycling rechargeable zinc-air batteries for efficient sustainable energy storage.
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Rechargeable zinc-air batteries are considered as next-generation energy storage devices because of their ultrahigh theoretical energy density of 1086â Wh kg-1 (including oxygen) and inherent safety originating from the use of aqueous electrolyte. However, the cathode processes regarding oxygen reduction and evolution are sluggish in terms of kinetics, which severely limit the practical battery performances. Developing high-performance bifunctional oxygen electrocatalysts is of great significance, yet to achieve better bifunctional electrocatalytic reactivity beyond the state-of-the-art noble-metal-based electrocatalysts remains a great challenge. Herein, a composite Co3 O4 @POF (POF=framework porphyrin) bifunctional oxygen electrocatalyst is proposed to construct advanced air cathodes for high-performance rechargeable zinc-air batteries. The as-obtained composite Co3 O4 @POF electrocatalyst exhibits a bifunctional electrocatalytic reactivity of ΔE=0.74â V, which is better than the noble-metal-based Pt/C+Ir/C electrocatalyst and most of the reported bifunctional ORR/OER electrocatalysts. When applied in rechargeable zinc-air batteries, the Co3 O4 @POF cathode exhibits a reduced discharge-charge voltage gap of 1.0â V at 5.0â mA cm-2 , high power density of 222.2â mW cm-2 , and impressive cycling stability for more than 2000â cycles at 5.0â mA cm-2 .