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Silicon (Si), a promising candidate for next-generation lithium-ion battery anodes, is still hindered by its volume change issue for (de)­lithiation, thus resulting in tremendous capacity fading. Designing carbon-modified Si materials with a void-preserving structure (Si@void@C) can effectively solve this issue. The preparation of Si@void@C, however, usually depended on template-based routes or chemical vapor deposition, which involve toxic reagents, tedious operation processes, and harsh conditions. Here, a facile templateless approach for preparing Si@void@C materials is reported through controlling the growth kinetics of resin, without the use of toxic hydrofluoric acid or harsh conditions. This approach allows great flexibility in tuning the crucial parameters of Si@void@C, such as the carbon shell thickness, the reserved void size, and the number of Si cores coated by a carbon shell. The optimized Si@void@C delivers a large specific capacity (1993.2 mAh g–1 at 0.1 A g–1), excellent rate performance (799.4 mAh g–1 at 10.0 A g–1), and long cycle life (73.5% capacity retention after 1000 cycles at 2.0 A g–1). In addition, a full cell fabricated with a Si@void@C anode and commercial LiFePO4 cathode also displays an impressive cycling performance.

Structural modulation endows electrochemical hybrids with promising energy storage properties owing to their adjustable interfacial and/or electronic characteristics. For MXene‐based materials, however, the facile but effective strategies for tuning their structural properties at nanoscale are still lacking. Herein, 3D crumpled S‐functionalized Ti3C2Tx substrate is rationally integrated with Fe3O4/FeS heterostructures via coprecipitation and subsequent partial sulfurization to induce a highly active and stable electrode architecture. The unique heterostructures with tuned electronic properties can induce improved kinetics and structural stability. The surface engineering by S terminations on the MXene further unlocks extra (pseudo)capacitive lithium storage. Serving as anode for lithium storage, the optimized electrode delivers an excellent long‐term cycling stability (913.9 mAh g−1 after 1000 cycles at 1 A g−1) and superior rate capability (490.4 mAh g−1 at 10 A g−1). Moreover, the (de)lithiation pathways associated with energy storage mechanisms are further revealed by operando X‐ray diffraction, in situ electroanalytical techniques, and first‐principles calculations. The hybrid electrode is proved to undergo stepwise phase transformations during discharging but a relatively uniform reconversion during charging, suggesting an asymmetric conversion mechanism. This work provides a novel strategy for designing high‐performance hybrids and paves the way for in‐depth understanding of complex lithium intercalation and conversion reactions.

Background Health literacy is defined as the cognitive and social skills that determine the motivation and ability of individuals to gain access to, understand and use information in ways that promote and maintain good health. A Health Literacy Questionnaire (HLQ) is a toolkit with good reliability and validity. Accordingly, this study administered HLQ among older adults in China to examine its factor structure, reliability, homogeneity, and discriminant validity for use in understanding better the health literacy of older adults and determining corresponding measures. Methods Psychometric properties were examined based on the data collected via face-to-face interviews ( N = 343). Tests included the difficulty level, composite scale reliability, confirmatory factor analysis (CFA), and Bayesian structural equation modeling (BSEM). Results The easiest scale to obtain a high score was “Social support for health” and the hardest, “Navigating the health care system” and “Appraisal of health information.” Two one-factor models fitted well with no correlated residuals allowed. After model modification, the CFA fit statistics of the other seven scales were good. All HLQ scales were found to be homogenous, with a composite reliability ranging from 0.74 to 0.85. The nine-factor Bayesian structural equation model fitted the data well (Posterior-Predictive-P value = 0.670; 95% Confidence Interval for the difference between the observed and replicated Chi-square values = − 163.320, 102.750). Conclusions The Chinese version of the HLQ has strong construct and content validity and high composite reliability when applied to older adults in Changsha City, China. Therefore, the nine-scale HLQ can now be administered to Chinese older adults, thereby providing a powerful approach to understanding the multidimensional area of health literacy.

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A 3D lithiophilic N-doped graphene/nickel foam (NGNF) scaffold to host Li has been successfully prepared by a simple hydrothermal method. This scaffold can improve the poor lithiophilicity of nickel foam (NF) due to the presence of N-doped graphene (NG) with lithiophilic functional groups while maintaining its 3D porous electrode structure, leading to uniform Li plating/stripping.

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Although Na metal is regarded as one of the most promising anode materials for Na-based batteries because of its high specific capacity (1166 mA h g–1) and low redox potential (−2.71 V versus the standard hydrogen electrode), many issues, such as dendrite-induced safety concerns, low efficiency, and poor cyclability, severely impede its practical application. Herein, to alleviate the abovementioned problems, a nitrogen-doped graphene-modified three dimensional nickel foam framework was constructed as the host material for Na plating. The sodiophilic N-containing functional groups in the graphene structure can effectively reduce the nucleation overpotential of Na, guide the homogeneous Na-ion flux, regularize the electric field distribution, and eventually inhibit Na dendrite formation. As a result, the Na composite metal anode can be cycled reversibly free from dendrite obsessions with a high Coulombic efficiency exceeding 99% at 0.5 mA cm–2, 1 mA h cm–2 for at least 800 cycles and 99% at 1 mA cm–2, 2 mA h cm–2 for at least 200 cycles. Based on this anode, a symmetric cell with ultralow voltage polarization (∼11 mV) and long-running lifespan (1000 h at 1 mA cm–2 for 1 mA h cm–2) can be realized. Furthermore, a full cell coupled with a Na3V2(PO4)3 cathode delivers a prolonged lifespan (250 cycles at 2 C) and excellent rate performances, demonstrating a facile but effective avenue to achieve Na metal anode stabilization.