An artificial while very stable solid electrolyte interphase film is formed on lithium metal using an electrochemical strategy. When this protected Li anode is first used in a Li–O2 battery, the film ...formed on the anode can effectively suppress the parasitic reactions on the Li anode/electrolyte interface and significantly enhance the cycling stability of the Li–O2 battery.
Reactive oxygen species (ROS)‐based cancer therapy, such as photodynamic therapy (PDT), is subject to the hypoxia and overexpressed glutathione (GSH) found in the tumor microenvironment (TME). ...Herein, a novel strategy is reported to continuously and simultaneously regulate tumor hypoxia and reducibility in order to achieve the desired therapeutic effect. To accomplish this, a biocompatible nanoplatform (MnFe2O4@metal–organic framework (MOF)) is developed by integrating a coating of porphyrin‐based MOF as the photosensitizer and manganese ferrite nanoparticle (MnFe2O4) as the nanoenzyme. The synthetic MnFe2O4@MOF nanoplatform exhibits both catalase‐like and glutathione peroxidase‐like activities. Once internalized in the tumor, the nanoplatform can continuously catalyze H2O2 to produce O2 to overcome the tumor hypoxia by cyclic Fenton reaction. Meanwhile, combined with the Fenton reaction, MnFe2O4@MOF is able to persistently consume GSH in the presence of H2O2, which decreases the depletion of ROS upon laser irradiation during PDT and achieves better therapeutic efficacy in vitro and in vivo. Moreover, the nanoplatform integrates a treatment modality with magnetic resonance imaging, along with persistent regulation of TME, to promote more precise and effective treatment for future clinical application.
A hydrogen peroxide (H2O2)‐responsive MnFe2O4@MOF nanostructure with continuous auto‐generating oxygen and meanwhile decreasing glutathione capacity in the tumor microenvironment (TME) is developed for enhancing the photodynamic therapy antitumor therapeutic effect. This multifunctional nanoplatform integrating treatment and imaging, along with continuous modulation of TME, could promote more precise and effective treatment in future clinical applications.
To recycle rusty stainless‐steel meshes (RSSM) and meet the urgent requirement of developing high‐performance cathodes for potassium‐ion batteries (KIB), we demonstrate a new strategy to fabricate ...flexible binder‐free KIB electrodes via transformation of the corrosion layer of RSSM into compact stack‐layers of Prussian blue (PB) nanocubes (PB@SSM). When further coated with reduced graphite oxide (RGO) to enhance electric conductivity and structural stability, the low‐cost, stable, and binder‐free RGO@PB@SSM cathode exhibits excellent electrochemical performances for KIB, including high capacity (96.8 mAh g−1), high discharge voltage (3.3 V), high rate capability (1000 mA g−1; 42 % capacity retention), and outstanding cycle stability (305 cycles; 75.1 % capacity retention).
Turning waste into treasure: Rusty stainless steel meshes were utilized as solid‐state iron sources with excellent conductivity properties in order to fabricate stable, low‐cost, and flexible binder‐free potassium‐ion battery electrodes. When combined with unique structural design, the reduced graphite oxide‐coated electrodes exhibited high capacities, superior rate capabilities, and excellent cycle performance.
To determine if 'Defocus Incorporated Multiple Segments' (DIMS) spectacle lenses slow childhood myopia progression.
A 2-year double-masked randomised controlled trial was carried out in 183 Chinese ...children aged 8-13 years, with myopia between -1.00 and -5.00 D and astigmatism ≤1.50 D. Children were randomly assigned to wear DIMS (n=93) or single vision (SV) spectacle lenses (n=90). DIMS lens incorporated multiple segments with myopic defocus of +3.50 D. Refractive error (cycloplegic autorefraction) and axial length were measured at 6month intervals.
160 children completed the study, n=79 in the DIMS group and n=81 in the SV group. Average (SE) myopic progressions over 2 years were -0.41±0.06 D in the DIMS group and -0.85±0.08 D in the SV group. Mean (SE) axial elongation was 0.21±0.02 mm and 0.55±0.02 mm in the DIMS and SV groups, respectively. Myopia progressed 52% more slowly for children in the DIMS group compared with those in the SV group (mean difference -0.44±0.09 D, 95% CI -0.73 to -0.37, p<0.0001). Likewise, children in the DIMS group had less axial elongation by 62% than those in the SV group (mean difference 0.34±0.04 mm, 95% CI 0.22 to 0.37, p<0.0001). 21.5% children who wore DIMS lenses had no myopia progression over 2 years, but only 7.4% for those who wore SV lenses.
Daily wear of the DIMS lens significantly retarded myopia progression and axial elongation in myopic children. Our results demonstrated simultaneous clear vision with constant myopic defocus can slow myopia progression.
NCT02206217.
To turn waste into treasure, a facile and cost‐effective strategy is developed to revive electroless nickel plating wastewater and cotton‐textile waste toward a novel electrode substrate. Based on ...the substrate, a binder‐free PB@GO@NTC electrode is obtained, which exhibits superior electrochemical performance. Moreover, for the first time, a novel tube‐type flexible and wearable sodium‐ion battery is successfully fabricated.
With the rising demand for flexible and wearable electronic devices, flexible power sources with high energy densities are required to provide a sustainable energy supply. Theoretically, ...rechargeable, flexible Li‐O2/air batteries can provide extremely high specific energy densities; however, the high costs, complex synthetic methods, and inferior mechanical properties of the available flexible cathodes severely limit their practical applications. Herein, inspired by the structure of human blood capillary tissue, this study demonstrates for the first time the in situ growth of interpenetrative hierarchical N‐doped carbon nanotubes on the surface of stainless‐steel mesh (N‐CNTs@SS) for the fabrication of a self‐supporting, flexible electrode with excellent physicochemical properties via a facile and scalable one‐step strategy. Benefitting from the synergistic effects of the high electronic conductivity and stable 3D interconnected conductive network structure, the Li‐O2 batteries obtained with the N‐CNTs@SS cathode exhibit superior electrochemical performance, including a high specific capacity (9299 mA h g−1 at 500 mA g−1), an excellent rate capability, and an exceptional cycle stability (up to 232 cycles). Furthermore, as‐fabricated flexible Li‐air batteries containing the as‐prepared flexible super‐hydrophobic cathode show excellent mechanical properties, stable electrochemical performance, and superior H2O resistibility, which enhance their potential to power flexible and wearable electronic devices.
Inspired by blood capillary tissue, a self‐standing, flexible N‐CNTs@SS Li‐O2 battery cathode with an interpenetrative structure is fabricated via a facile and scalable one‐step strategy. The flexible Li‐O2 batteries with N‐CNTs@SS exhibit excellent mechanical properties, stable electrochemical performance, and superior H2O resistibility.
Inspired by the favorable structure and shape of golden‐toad eggs, a self‐standing macroporous active carbon fiber electrode is designed and fabricated via a facile and scalable strategy. After being ...decorated with ruthenium oxide, it endows Li–O2 batteries with superior electrochemical performances.
Rechargeable sodium–oxygen (Na–O2) batteries are of interest due to their high specific capacity, high equilibrium potential output, and the abundance of sodium resources; however, their cycle life ...is still very poor due to instability of electrolytes and especially the uncontrollable growth of Na dendrites. Herein, as a proof‐of‐concept experiment, a facile and low‐cost strategy is first proposed and demonstrated to effectively suppress growth of Na dendrites by using a fibrillar polyvinylidene fluoride film (f‐PVDF) with nonthrough pore as a multifunctional blocking interlayer. Unexpectedly, the f‐PVDF interlayer endows Na–O2 battery with superior electrochemical performances, including high rate capability and long cycle life (up to 87 cycles), which is superior to those of the compact PVDF (c‐PVDF), PVDF with through pores (p‐PVDF), polyethylene oxide (PEO), and conventional polytetrafluoroethylene (PTFE) counterparts due to the following combined advantages: (1) the stronger CF polar function groups provide a better affinity to Na ions, thus enabling a more homogeneous Na deposition than that of CO function groups in PEO interlayer; (2) compared with c‐PVDF and p‐PVDF interlayers, f‐PVDF holds more electrolyte uptake for higher ion conductivity; (3) the good wettability of the f‐PVDF interlayer with electrolyte benefits Na dendrite suppression compared with PTFE interlayer.
Stable and fibrillar polyvinylidene fluoride films (f‐PVDFs) with strongly polar functional groups are prepared as the blocking interlayer for Na dendrites suppression. Surprisingly, the films efficiently suppress dendrite formation and greatly improve the cycle life of Na–O2 batteries, which is attributed to f‐PVDF's high electrolyte uptake, good adhesion to Na ionic flux, and excellent affinity to the electrolyte.
To promote the development of high energy Li–O2 batteries, it is important to design and construct a suitable and effective oxygen‐breathing cathode. Herein, activated cobalt‐nitrogen‐doped carbon ...nanotube/carbon nanofiber composites (Co‐N‐CNT/CNF) as the effective cathodes for Li–O2 batteries are prepared by in situ chemical vapor deposition (CVD). The unique architecture of these electrodes facilitates the rapid oxygen diffusion and electrolyte penetration. Meanwhile, the nitrogen‐doped carbon nanotube/carbon nanofiber (N‐CNT/CNF) and Co/CoNx serve as reaction sites to promote the formation/decomposition of discharge product. Li–O2 batteries with Co‐N‐CNT/CNF cathodes exhibit superior electrochemical performance in terms of a positive discharge plateau (2.81 V) and a low charge overpotential (0.61 V). Besides, Li–O2 batteries also present a high discharge capacity (11512.4 mAh g−1 at 100 mA g−1), and a long cycle life (130 cycles). Meanwhile, the Co‐N‐CNT/CNF cathode also has an excellent flexibility, thus the assembled flexible battery with Co‐N‐CNT/CNF can work normally and hold a wonderful capacity rate under various bending conditions.
Activated cobalt‐nitrogen‐doped carbon nanotube/carbon nanofiber composites (Co‐N‐CNT/CNF) cathodes are prepared via in situ chemical vapor deposition. The Li–O2 batteries with these cathodes exhibit great performances. Meanwhile, Co‐N‐CNT/CNF cathodes are flexible, based on which the assembled flexible battery exhibits great performances and flexibility under various bending conditions.
Metallic carbon nanotubes (CNTs) have received much attention for their unique characteristics as a possible alternative to Cu interconnects in future ICs. Until this date, while almost all ...fabrication efforts have been directed toward multiwalled CNT (MWCNT) interconnects, there is a lack of MWCNT modeling work. This paper presents, for the first time, a detailed investigation of MWCNT-based interconnect performance. A compact equivalent circuit model of MWCNTs is presented for the first time, and the performance of MWCNT interconnects is evaluated and compared against traditional Cu interconnects, as well as Single-Walled CNT (SWCNT)-based interconnects, at different interconnect levels (local, intermediate, and global) for future technology nodes. It is shown that at the intermediate and global levels, MWCNT interconnects can achieve smaller signal delay than that of Cu interconnects, and the improvements become more significant with technology scaling and increasing wire lengths. At 1000- global or 500- intermediate level interconnects, the delay of MWCNT interconnects can reach as low as 15% of Cu interconnect delay. It is also shown that in order for SWCNT bundles to outperform MWCNT interconnects, dense and high metallic-fraction SWCNT bundles are necessary. On the other hand, since MWCNTs are easier to fabricate with less concern about the chirality and density control, they can be attractive for immediate use as horizontal wires in VLSI, including local, intermediate, and global level interconnects.
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