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Water splitting is a critical process for the production of green hydrogen, contributing to the advancement of a circular economy. However, the application of water splitting devices on a large scale is primarily impeded by the sluggish oxygen evolution reaction (OER) at the anode. Thus, developing and designing efficient OER catalysts is a significant target. NiFe‐based catalysts are extensively researched as excellent OER electrocatalysts due to their affordability, abundant reserves, and intrinsic activities. However, they still suffer from long‐term stability challenges. To date, few systematic strategies for improving OER durability have been reported. In this review, various advanced NiFe‐based catalysts are introduced. Moreover, the OER stability challenges of NiFe‐based electrocatalysts in alkaline media, including iron segregation, structural degradation, and peeling from the substrate are summarized. More importantly, strategies to enhance OER stability are highlighted and opportunities are discussed to facilitate future stability studies for alkaline water electrolysis. This review presents a design strategy for NiFe‐based electrocatalysts and anion exchange membrane (AEM) electrolyzers to overcome stability challenges in OER, which also emphasizes the importance of long‐term stability in alkaline media and its significance for achieving large‐scale commercialization. [ABSTRACT FROM AUTHOR]

Developing high‐performance anode current collectors with three‐dimensional structure and lithiophilic layers is of great importance to further advance the application of lithium metal batteries. However, relatively few research has focused on the transition of substrate and the intrinsic structure stability after electrodeposition of lithium on substrates, which leads to an incomplete understanding of the behavior of lithium deposition. Herein, a lithium metal anodes host with a highly stable and 3D structure has been effectively produced through in situ development of nanoflake arrays embedded with Co3O4 obtained from ZIF on nickel foams (Co3O4‐NF). And the actual lithium deposition sites and lithium deposition process on Co3O4‐NF are elucidated via a combination of characterization techniques and electrochemical analytical methods. Consequently, the resulting Co3O4‐NF@Li anodes could effectively inhibit lithium dendrite formation and mitigate volume expansion, demonstrating a significantly extended and consistent lifespan of 800 cycles (1600 h) at 1 mA cm−2 with low overpotential and insignificant voltage fluctuation for the process of lithium stripping and plating in symmetric cells. Herein, it is aimed to examine the transitions of metal oxides as a lithiophilic site for the lithium metal anode. It offers novel perspectives and approaches for the design of dendrite‐free lithium metal anodes. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are considered as important candidate materials for energy storage systems (EES) due to high Earth abundance and low cost of sodium resources. Among all cathode materials for SIBs, polyanion‐type materials can provide high ionic conductivity and high structural stability, simultaneously, due to the 3D network structure. Their rich variety also provides more options for the commercialization of SIBs. However, the majority of polyanion‐type materials are not suitable for commercialization due to either high costs or complex preparation process. Herein, low‐cost polyanion‐type materials that are suitable for the commercialization of SIBs are discussed. The latest developments of polyanion‐type materials are overviewed. Furthermore, the challenges and countermeasures of polyanion‐type materials are summarized. This review can provide valuable insights for the commercialization of polyanion‐type materials. [ABSTRACT FROM AUTHOR]

Ion exchange membranes (IEMs) play important roles in energy generation and storage field, such as fuel cell, flow battery, however, a major barrier in the way of large‐scale application is the high cost of membranes (e.g., Nafion membranes price generally exceeds USD$ 200 m−2). The membrane‐less technology is one of the promising approaches to solve the problem and thus has attracted much attention and been explored in a variety of research paths. This review introduces one of the representative membrane‐less battery types, Biphasic membrane‐less redox batteries that eliminate the IEMs according to the principle of solvent immiscibility and realizes the phase splitting in a thermodynamically stable state. It is systematically classified and summarizes their performances as well as the problems they are suffering from, and then several effective solutions are proposed based on the modification of electrodes and electrolytes. Finally, special attention is given to the challenges and prospects of Biphasic membrane‐less redox batteries, which could contribute to the development of membrane‐less batteries. [ABSTRACT FROM AUTHOR]

To explore the application of neural network algorithm model in lung cancer imaging, and provide reference for the application and development of artificial neural network (ANN) algorithm model in lung cancer medical mirroring, so as to promote the development of ANN in this field. Meanwhile, it is hoped that the application of neural network algorithms in medical imaging can improve the survival rate and cure rate of lung cancer. In this study, an ANN algorithm model was selected to establish a lung cancer recognition model. After determining the lung cancer lesion area, the image segmentation algorithm was used to separately display the lung cancer lesion area, and a comparison experiment was designed to verify the accuracy of the model. ANNs were used to identify lung cancer, which can be concluded that the accuracy is 94.6%, the sensitivity is 95.7%, and the specificity is 93.5%. By combining image retrieval methods with lung cancer image segmentation algorithms, the lesion area of lung cancer can be clearly displayed. Therefore, the lung cancer image segmentation algorithm based on the neural network model has good recognition performance. This research can provide reference for the application of neural network algorithm model in the field of cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Rational design of bifunctional efficient electrocatalysts for both oxygen reduction (ORR) and oxygen evolution reactions (OER) is desirable—while highly challenging—for development of rechargeable metal–air batteries. Herein, an efficient bifunctional electrocatalyst is designed and fabricated by encapsulating Co nanoparticles in interconnected N‐doped hollow porous carbon nanofibers (designated as Co@N‐C/PCNF) using an ultrafast high‐temperature shock technology. Benefiting from the synergistic effect and intrinsic activity of the CoNC moiety, as well as porous structure of carbon nanofibers, the Co@N‐C/PCNF composite shows high bifunctional electrocatalytic activities for both OER (289 mV at 10 mA cm−2) and ORR (half‐wave potential of 0.85 V). The CoNC moiety in the composite can modulate the local environmental and electrical structure of the catalysts, thus optimizing the adsorption/desorption kinetics and decreasing the reaction barriers for promoting the reversible oxygen electrocatalysis. Co@N‐C/PCNF‐based aqueous Zn–air batteries (AZAB) provide high power density of 292 mW cm−2, and the assembled flexible ZAB can power wearable devices. [ABSTRACT FROM AUTHOR]

With the low redox potential of −3.04 V (vs SHE) and ultrahigh theoretical capacity of 3862 mAh g−1, lithium metal has been considered as promising anode material. However, lithium metal battery has ever suffered a trough in the past few decades due to its safety issues. Over the years, the limited energy density of the lithium‐ion battery cannot meet the growing demands of the advanced energy storage devices. Therefore, lithium metal anodes receive renewed attention, which have the potential to achieve high‐energy batteries. In this review, the history of the lithium anode is reviewed first. Then the failure mechanism of the lithium anode is analyzed, including dendrite, dead lithium, corrosion, and volume expansion of the lithium anode. Further, the strategies to alleviate the lithium anode issues in recent years are discussed emphatically. Eventually, remaining challenges of these strategies and possible research directions of lithium‐anode modification are presented to inspire innovation of lithium anode. [ABSTRACT FROM AUTHOR]