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Creating defects by heteroatom doping is commonly approved in respect of enhancing fast sodium‐ion storage of carbonaceous anodes ascribing to rich external defects, but the contribution of intrinsic carbon defects (e.g., vacancy) in improving rate‐capability has rarely been investigated. Here, a bio‐derived fibrous hard carbon with high‐reversible intrinsic defects is synthesized via metal‐assisted‐catalytic strategy. It is found that sp2‐hybridized carbon is united through catalytic‐tuning during thermal‐etching process along with the formation of low‐potential planar intrinsic carbon defects (vacancies and non‐hexagonal carbon rings) by sacrificing poor‐reversible carbon edges. Such integrated structures greatly improve the reversibility of defective sites and charge transfer kinetics, thus enhancing the slope sodium‐storage capacity of carbon below 1 V even at high current densities. Thus‐obtained fibrous carbon anodes enable boosted initial coulombic efficiency (≈90%) and ultrahigh‐rate capability in both half‐ (222.2 mAh g−1at 50 A g−1) and full‐cell (200 C, charged/discharged in ≈10 s). Interestingly, compared with meso‐/macroporous structures, such micropore‐dominated carbon fibers are more beneficial for fabricating high‐mass‐loading, crack‐free thick electrodes (>10 mg cm−2) with considerable areal‐capacity over 3.0 mAh cm−2. Paired with high‐loading Na3V2PO4 cathode (14.4 mg cm−2), full‐cell achieves admirable areal‐capacity over 1.4 mAh cm−2 and peak areal‐energy/power‐density of 3.2/74 mW cm−2. [ABSTRACT FROM AUTHOR]

Efficient energy storage devices with suitable electrode materials, that integrate high power and high energy, are the crucial requisites of the renewable power source, which have unwrapped new possibilities in the sustainable development of energy and the environment. Herein, a facile collagen microstructure modulation strategy is proposed to construct a nitrogen/oxygen dual‐doped hierarchically porous carbon fiber with ultrahigh specific surface area (2788 m2 g−1) and large pore volume (4.56 cm3 g−1) via local microfibrous breakage/disassembly of natural structured proteins. Combining operando spectroscopy and density functional theory unveil that the dual‐heteroatom doping could effectively regulate the electronic structure of carbon atom framework with enhanced electric conductivity and electronegativity as well as decreased diffusion resistance in favor of rapid pseudocapacitive‐dominated Li+‐storage (353 mAh g−1 at 10 A g−1). Theoretical calculations reveal that the tailored micro−/mesoporous structures favor the rapid charge transfer and ion storage, synergistically realizing high capacity and superior rate performance for NPCF‐H cathode (75.0 mAh g−1 at 30 A g−1). The assembled device with NPCF‐H as both anode and cathode achieves extremely high energy density (200 Wh kg−1) with maximum power density (42 600 W kg−1) and ultralong lifespan (80% capacity retention over 10 000 cycles). [ABSTRACT FROM AUTHOR]

To achieve both high gravimetric and volumetric energy densities of lithium–sulfur (Li–S) batteries, it is essential yet challenging to develop low‐porosity dense electrodes along with diminishment of the electrolyte and other lightweight inactive components. Herein, a compact TiO2@VN heterostructure with high true density (5.01 g cm–3) is proposed crafted by ingenious selective nitridation, serving as carbon‐free dual‐capable hosts for both sulfur and lithium. As a heavy S host, the interface‐engineered heterostructure integrates adsorptive TiO2 with high conductive VN and concurrently yields a built‐in electric field for charge‐redistribution at the TiO2/VN interfaces with enlarged active locations for trapping‐migration‐conversion of polysulfides. Thus‐fabricated TiO2@VN–S composite harnessing high tap‐density favors constructing dense cathodes (≈1.7 g cm–3) with low porosity (<30 vol%), exhibiting dual‐boosted cathode‐level peak volumetric‐/gravimetric‐energy‐densities nearly 1700 Wh L−1cathode/1000 Wh kg−1cathode at sulfur loading of 4.2 mg cm−2 and prominent areal capacity (6.7 mAh cm−2) at 7.6 mg cm−2 with reduced electrolyte (<10 µL mg−1sulfur). Particular lithiophilicity of the TiO2@VN is demonstrated as Li host to uniformly tune Li nucleation with restrained dendrite growth, consequently bestowing the assembled full‐cell with high electrode‐level volumetric/gravimetric‐energy‐density beyond 950 Wh L−1cathode+anode/560 Wh kg−1cathode+anode at 3.6 mg cm−2 sulfur loading alongside limited lithium excess (≈50%). [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to explore the relationship between the natural environment of residential areas and the subjective wellbeing of the elderly and the role of elderly's evaluation of the government's environmental protection work in both., Methods: Based on the China Social Survey Database in 2013, 2015, 2017, 2019, Stata were used to process the data screened according to the restricted conditions. Ordered Probit Model and Sobel were used to test the effect relationship among the variables., Results: The subjective wellbeing of the elderly is roughly increasing. The natural environment of the living area has a significant positive effect on the subjective wellbeing of the elderly. The evaluation of the elderly on the government's environmental protection work has a positive impact on the elderly's subjective wellbeing similarly and plays an increasingly important intermediary role in the impact of the natural environment in the residential area on the elderly's subjective wellbeing., Conclusion: To improve the subjective wellbeing of the elderly, the government should continue to play a leading role in coordinating environmental protection and pollution control, strengthen publicity of environmental protection work. Moreover, improve the residential environment governance and protection system oriented by the elderly's evaluation of the government's environmental protection work., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Jiang, Jin, Pu and Li.)

To improve the innate shuttle effect and the sluggish redox kinetics of lithium-sulfur batteries, a composite made of a bimetallic compound embedded in nitrogen-doped carbon nanofibers (CNFs) is synthesized by employing biomass collagen fibers (CFs) as a structure template. Metal anions WO 4 2- and MoO 4 2- are grafted on plant polyphenol-modified CFs and then in situ converted into WN/Mo 2 C implanted in a matrix of CNFs (WMCNFs). The obtained WN/Mo 2 C is of quantum size and uniform distribution, exposing the active sites maximally. Further, the heterostructure of the bimetallic composite enables unique electronic interaction, thereby synergistically enhancing its adsorption capability toward soluble intermediates and activating its catalytic function for liquid-liquid and liquid-solid conversions. Combining these merits, when used as a separator modification material and a sulfur host simultaneously, the WMCNFs composite exhibits remarkable cycling stability with 91.45% capacity retention after 500 cycles at 2 C and also prominent rate performance of delivering 552.75 mAh g -1 at a current rate of 10 C. Meanwhile, the stable luminescence operation of LED lights powered by the assembled pouch cell demonstrates the application potential of this biomaterial-derived composite.