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Research on high‐efficiency and cost‐efficient catalysts for oxygen reduction reaction (ORR) is still a vital but challenging issue for commercializing metal–air batteries. Herein, a single‐molecule/atom hybrid catalyst is developed to boost the ORR, in which iron phthalocyanine molecules containing molecular Fe─N4 moieties couple with atomic Co─N4 sites on the surface of polyhedral carbon. Density functional theory calculations reveal that face‐to‐face laminated construction of Fe─N4 and Co─N4 in the hybrid catalyst can effectively modulate the electronic structure of active iron atoms and reduce the energy barrier of the rate‐determining step for ORR. As a result, this hybrid catalyst demonstrates excellent ORR performance, featuring a half‐wave potential of 0.904 V, a peak power density of 238.3 mW cm−2 for zinc–air battery, and outstanding electrocatalytic stability. This work offers a distinctive and robust molecular/atomic engineering approach to creating efficient electrocatalysts, advancing the fields of metal–air batteries. [ABSTRACT FROM AUTHOR]

Remote limb conditioning (RLC), performed by intermittent interruption of blood flow to a limb, triggers endogenous tolerance mechanisms and improves stroke outcomes. The underlying mechanism for the protective effect involves a shift of circulating monocytes to a Ly6CHigh proinflammatory subset in normal metabolic conditions. The current study investigates the effect of RLC on stroke outcomes in subjects with obesity, a vascular comorbidity. Compared to lean mice, obese stroke mice displayed significantly higher circulating monocytes (monocytosis), increased CD45High monocytes/macrophages infiltration to the injured brain, worse acute outcomes, and delayed recovery. Unlike lean mice, obese mice with RLC at 2 hours post-stroke failed to shift circulating monocytes to pro-inflammatory status and nullified RLC-induced functional benefit. The absence of the monocyte shift was also observed in splenocytes incubated with RLC serum from obese mice, while the shift was observed in the cultures with RLC serum from lean mice. These results showed that the alteration of monocytosis and subsets underlies negating RLC benefits in obese mice and suggest careful considerations of comorbidities at the time of RLC application for stroke therapy. [ABSTRACT FROM AUTHOR]

A novel NiO/MnO2 pompon-like hybrid structure was synthesized through a facile one-step hydrothermal in situ growth approach in this paper. NiO nanosheets grow on MnO2 pompon-like microsphere to form typical hybrid structures which significantly increase the abundant active sites of electrode materials. The resulting NiO/MnO2 electrode material exhibits an impressive specific capacity of 2706.1 F/g at a current density of 1 A/g. Remarkably, NiO/MnO2 pompon-like hybrid structure shows excellent cycling performance and its capacity retention is maintained at 84.8% and the charge–discharge efficiency at 96% after 15,000 cycles. Even after undergoing 40,000 cycles, the electrode material maintains an outstanding charge–discharge efficiency of 95.2% with capacity retention of 69%, which revealing promising application as long-term electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) with low cost and high safety are considered as an electrochemical energy storage technology suitable for large-scale energy storage. Hard carbon, which is inexpensive and has both high capacity and low sodium storage potential, is regarded as the most promising anode for commercial SIBs. However, the commercialization of hard carbon still faces technical issues of low initial Coulombic efficiency, poor rate performance, and insufficient cycling stability, due to the intrinsically irregular microstructure of hard carbon. To address these challenges, the rational design of the hard carbon microstructure is crucial for achieving highperformance SIBs, via gaining an in-depth understanding of its structure--performance correlations. In this context, our review firstly describes the sodium storage mechanism from the perspective of the hard carbon microstructure's formation. We then summarize the state-of-art development of hard carbon, providing a critical overview of emergence of hard carbon in terms of precursor selection, microstructure design, and electrolyte regulation to optimize strategies for addressing practical problems. Finally, we highlight directions for the future development of hard carbon to achieve the commercialization of high-performance SIBs. We believe this review will serve as basic guidance for the rational design of hard carbon and stimulate more exciting research into other types of energy storage devices. [ABSTRACT FROM AUTHOR]