Surface and Bulk Stabilization of Silicon Anodes with Mixed-Multivalent Additives: Ca(TFSI)2 and Mg(TFSI)2.

Silicon is drawing attention as an emerging anode material for the next generation of lithium-ion batteries due to its higher capacity compared with commercial graphite. However, silicon anions formed during lithiation are highly reactive with binder and electrolyte components, creating an unstable SEI layer and limiting the calendar life of silicon anodes. The reactivity of lithium silicide and the formation of an unstable SEI layer are mitigated by utilizing a mixture of Ca and Mg multivalent cations as an electrolyte additive for Si anodes to improve their calendar life. The effect of mixed salts on the bulk and surface of the silicon anodes was studied by multiple structural characterization techniques. Ca and Mg ions in the electrolyte formed relatively thermodynamically stable quaternary Li-Ca-Mg-Si Zintl phases in an in situ fashion and a more stable and denser SEI layer on the Si particles. These in turn protect silicon particles against side reactions with electrolytes in a coin cell. The full cell with the mixed cation electrolyte demonstrates enhanced calendar life performance with lower measured current and current leakage in comparison to that of the baseline electrolyte due to reduced side reactions. Electron microscopy, HR-XRD, and solid-state NMR results showed that electrodes with mixed cations tended to have less cracking on the electrode surface, and the presence of mixed cations enhances cation migration and formation of quaternary Zintl phases stabilizing the bulk and forming a more stable SEI in comparison to baseline electrolyte and electrolyte with single multivalent cations.

Biomimetic Nanovehicle-Enabled Targeted Depletion of Intratumoral Fusobacterium nucleatum Synergizes with PD-L1 Blockade against Breast Cancer.

Immune checkpoint blockade (ICB) therapy has been approved for breast cancer (BC), but clinical response rates are limited. Recent studies have shown that commensal microbes colonize a variety of tumors and are closely related to the host immune system response. Here, we demonstrated that Fusobacterium nucleatum (F.n), which is prevalent in BC, creates an immunosuppressive tumor microenvironment (ITME) characterized by a high-influx of myeloid cells that hinders ICB therapy. Administering the antibiotic metronidazole in BC can deplete F.n and remodel the ITME. To prevent an imbalance in the systemic microbiota caused by antibiotic administration, we designed a biomimetic nanovehicle for on-site antibiotic delivery inspired by F.n homing to BC. Additionally, ferritin-nanocaged doxorubicin was coloaded into this nanovehicle, as immunogenic chemotherapy has shown potential for synergy with ICB. It has been demonstrated that this biomimetic nanovehicle can be precisely homed to BC and efficiently eliminate intratumoral F.n without disrupting the diversity and abundance of systemic microbiota. This ultimately remodels the ITME, improving the therapeutic efficacy of the PD-L1 blocker with a tumor inhibition rate of over 90% and significantly extending the median survival of 4T1 tumor-bearing mice.

Ultrasensitive Optical Detection and Elimination of Residual Microtumors with a Postoperative Implantable Hydrogel Sensor for Preventing Cancer Recurrence.

In vivo optical imaging of trace biomarkers in residual microtumors holds significant promise for cancer prognosis but poses a formidable challenge. Here, a novel hydrogel sensor is designed for ultrasensitive and specific imaging of the elusive biomarker. This hydrogel sensor seamlessly integrates a molecular beacon nanoprobe with fibroblasts, offering both high tissue retention capability and an impressive signal-to-noise ratio for imaging. Signal amplification is accomplished through exonuclease I-mediated biomarker recycling. The resulting hydrogel sensor sensitively detects the biomarker carcinoembryonic antigen with a detection limit of 1.8 pg mL-1 in test tubes. Moreover, it successfully identifies residual cancer nodules with a median diameter of less than 2 mm in mice bearing partially removed primary triple-negative breast carcinomas (4T1). Notably, this hydrogel sensor is proven effective for the sensitive diagnosis of invasive tumors in post-surgical mice with infiltrating 4T1 cells, leveraging the role of fibroblasts in locally enriching tumor cells. Furthermore, the residual microtumor is rapidly photothermal ablation by polydopamine-based nanoprobe under the guidance of visualization, achieving ≈100% suppression of tumor recurrence and lung metastasis. This work offers a promising alternative strategy for visually detecting residual microtumors, potentially enhancing the prognosis of cancer patients following surgical interventions.

Safe engineering of cancer-associated fibroblasts enhances checkpoint blockade immunotherapy.

Abundant cancer-associated fibroblasts (CAFs) in highly fibrotic breast cancer constitute an immunosuppressive barrier for T cell activity and are closely related to the failure of immune checkpoint blockade therapy (ICB). Inspired by the similar antigen-processing capacity of CAFs to professional antigen-presenting cells (APCs), a "turning foes to friends" strategy is proposed by in situ engineering immune-suppressed CAFs into immune-activated APCs for improving response rates of ICB. To achieve safe and specific CAFs engineering in vivo, a thermochromic spatiotemporal photo-controlled gene expression nanosystem was developed by self-assembly of molten eutectic mixture, chitosan andfusion plasmid. After photoactivatable gene expression, CAFs could be engineered as APCs via co-stimulatory molecule (CD86) expression, which effectively induced activation and proliferation of antigen-specific CD8 + T cells. Meanwhile, engineered CAFs could also secrete PD-L1 trap protein in situ for ICB, avoiding potential autoimmune-like disorders caused by "off-target" effects of clinically applied PD-L1 antibody. The study demonstrated that the designed nanosystem could efficiently engineer CAFs, significantly enhance the percentages of CD8+ T cells (4-folds), result in about 85% tumor inhibition rate and 83.3% survival rate at 60 days in highly fibrotic breast cancer, further inducing long-term immune memory effects and effectively inhibiting lung metastasis.

Probing the Reactivity of the Active Material of a Li-Ion Silicon Anode with Common Battery Solvents.

Calculations and modeling have shown that replacing the traditional graphite anode with silicon can greatly improve the energy density of lithium-ion batteries. However, the large volume change of silicon particles and high reactivity of lithiated silicon when in contact with the electrolyte lead to rapid capacity fading during charging/discharging processes. In this report, we use specific lithium silicides (LS) as model compounds to systematically study the reaction between lithiated Si and different electrolyte solvents, which provides a powerful platform to deconvolute and evaluate the degradation of various organic solvents in contact with the active lithiated Si-electrode surface after lithiation. Nuclear Magnetic Resonance (NMR) characterization results show that a cyclic carbonate such as ethylene carbonate is chemically less stable than a linear carbonate such as ethylmethyl carbonate, fluoroethylene carbonate, and triglyme as they are found to be more stable when mixed with LS model compounds. Guided by the experimental results, two ethylene carbonate (EC)-free electrolytes are studied, and the electrochemical results show improvements with graphite-free Si electrodes relative to the traditional ethylene-carbonate-based electrolytes. More importantly, the study contributes to our understanding of the significant fundamental chemical and electrochemical stability differences between silicon and traditional graphite lithium-ion battery (LIB) anodes and suggests a focused development of electrolytes with specific chemical stability vs lithiated silicon which can passivate the surface more effectively.

Few-layer graphene on nickel enabled sustainable dropwise condensation.

Condensation is critical for a wide range of applications such as electrical power generation, distillation, natural gas processing, dehumidification and water harvest, and thermal management. Compared with "filmwise" mode of condensation (FWC) prevailing in industrial-scale systems, dropwise condensation (DWC) can provide an order of magnitude higher heat transfer rate owing to drastically reduced thermal resistance from the formation of discrete and mobile droplets. In the past, promoting DWC by controlling surface wetting has attracted wide attention, but DWC highly relies on non-wetting surfaces and only lasts days under practical conditions due to the poor reliability of coatings. Here, we developed nanostructured graphene coatings on nickel (Ni) substrates that we can control and enhance the nucleation of water droplets on graphene grain boundaries. Surprisingly, this enables DWC even under normal "wetting" conditions. This is contradictory to the widely accepted DWC mechanism. Moreover, the Ni-graphene surface enables exceptional long-term condensation from days to more than 3 years under practical or even more aggressive testing environments.

Self-sustainable protonic ceramic electrochemical cells using a triple conducting electrode for hydrogen and power production.

The protonic ceramic electrochemical cell (PCEC) is an emerging and attractive technology that converts energy between power and hydrogen using solid oxide proton conductors at intermediate temperatures. To achieve efficient electrochemical hydrogen and power production with stable operation, highly robust and durable electrodes are urgently desired to facilitate water oxidation and oxygen reduction reactions, which are the critical steps for both electrolysis and fuel cell operation, especially at reduced temperatures. In this study, a triple conducting oxide of PrNi0.5Co0.5O3-δ perovskite is developed as an oxygen electrode, presenting superior electrochemical performance at 400~600 °C. More importantly, the self-sustainable and reversible operation is successfully demonstrated by converting the generated hydrogen in electrolysis mode to electricity without any hydrogen addition. The excellent electrocatalytic activity is attributed to the considerable proton conduction, as confirmed by hydrogen permeation experiment, remarkable hydration behavior and computations.

Bioinspired, graphene-enabled Ni composites with high strength and toughness.

Nature's wisdom resides in achieving a joint enhancement of strength and toughness by constructing intelligent, hierarchical architectures from extremely limited resources. A representative example is nacre, in which a brick-and-mortar structure enables a confluence of toughening mechanisms on multiple length scales. The result is an outstanding combination of strength and toughness which is hardly achieved by engineering materials. Here, a bioinspired Ni/Ni3C composite with nacre-like, brick-and-mortar structure was constructed from Ni powders and graphene sheets. This composite achieved a 73% increase in strength with only a 28% compromise on ductility, leading to a notable improvement in toughness. The graphene-derived Ni-Ti-Al/Ni3C composite retained high hardness up to 1000°C. The present study unveiled a method to smartly use 2D materials to fabricate high-performance metal matrix composites with brick-and-mortar structure through interfacial reactions and, furthermore, created an opportunity of developing advanced Ni-C-based alloys for high-temperature environments.

Lithiation-Aided Conversion of End-of-Life Lithium-Ion Battery Anodes to High-Quality Graphene and Graphene Oxide.

In the past two decades, lithium-ion (Li-ion) batteries have transformed the appearance of the world. Along with the ever-increasing production and usage are the tremendous number of retired batteries, which have created social and environmental issues, making battery recycling an urgent task. Graphene has exhibited outstanding electronic and mechanical properties but it is still difficult to fabricate high-quality graphene with feasible procedures at low cost. Here, a strategy of smartly converting retired Li-ion battery anodes to graphene and graphene oxide is proposed. The graphite powders collected from end-of-life Li-ion batteries exhibited irregular expansion because of the lithium-ion intercalation and deintercalation in the anodegraphite during battery charge/discharge. Such prefabrication process facilitated both chemical and physical exfoliations of the graphite. Comparing with the graphene oxide derived from pristine, untreated graphite, the graphene oxide from anodegraphite exhibited superlative homogeneity and electrochemical properties. The lithiation aided pre-expansion enabled 4 times enhancement of graphene productivity by shear mixing. Furthermore, the graphene fabrication was seamlessly inserted into the currently used battery recycling streamline in which the acid treatment was found to further swell the graphite lattice, pushing up the graphene productivity to 83.7% (10 times higher than that of pristine graphite powders). The findings create new opportunities for capitalizing on waste batteries to produce high-quality graphene and its derivatives.

3D Self-Architectured Steam Electrode Enabled Efficient and Durable Hydrogen Production in a Proton-Conducting Solid Oxide Electrolysis Cell at Temperatures Lower Than 600 °C.

Hydrogen production via water electrolysis using solid oxide electrolysis cells (SOECs) has attracted considerable attention because of its favorable thermodynamics and kinetics. It is considered as the most efficient and low-cost option for hydrogen production from renewable energies. By using proton-conducting electrolyte (H-SOECs), the operating temperature can be reduced from beyond 800 to 600 °C or even lower due to its higher conductivity and lower activation energy. Technical barriers associated with the conventional oxygen-ion conducting SOECs (O-SOECs), that is, hydrogen separation and electrode instability that is primarily due to the Ni oxidation at high steam concentration and delamination associated with oxygen evolution, can be remarkably mitigated. Here, a self-architectured ultraporous (SAUP) 3D steam electrode is developed for efficient H-SOECs below 600 °C. At 600 °C, the electrolysis current density reaches 2.02 A cm-2 at 1.6 V. Instead of fast degradation in most O-SOECs, performance enhancement is observed during electrolysis at an applied voltage of 1.6 V at 500 °C for over 75 h, attributed to the "bridging" effect originating from reorganization of the steam electrode. The H-SOEC with SAUP steam electrode demonstrates excellent performance, promising a new prospective for next-generation steam electrolysis at reduced temperatures.

Bioinspired, Multiscale Reinforced Composites with Exceptionally High Strength and Toughness.

Nature's multiscale reinforcing mechanisms in fabricating composite armors, such as seashells, provide lessons for engineering materials design and manufacturing. However, it is still a challenge to simultaneously add both micro- and nanoreinforcements in a matrix material since nano-fillers tend to agglomerate, decreasing their reinforcing effects. In this study, we report a new type of micro/nano hybrid filler, synthesized by an unconventional cotton aided method, which has B4C microplatelet as the core and radially aligned B4C nanowires as the shell. To enhance the bonding between the B4C fillers and epoxy, the B4C micro/nano-fillers were coated with a layer of polyaniline (PANI). With a low concentration of the PANI functionalized B4C micro/nano-fillers (1 wt %), this B4C/epoxy composite exhibited an exceptional combination of mechanical properties in terms of elastic modulus (∼3.47 GPa), toughness (2026.3 kJ/m3), and fracture strain (>3.6%). An analytical mechanics model was established to show that such multiscale reinforcement design remarkably enhanced the load carrying efficiency of the B4C fillers, leading to the overall improved mechanical performance of the composites. This new design concept opens up a new path for developing lightweight, yet high-strength and tough materials with multiscale reinforcing configurations.

A High-Performing Direct Carbon Fuel Cell with a 3D Architectured Anode Operated Below 600 °C.

Direct carbon fuel cells (DCFCs) are highly efficient power generators fueled by abundant and cheap solid carbons. However, the limited triple-phase boundaries (TPBs) in the fuel electrode, due to the lack of direct contact among carbon, electrode, and electrolyte, inhibit the performance and result in poor fuel utilization. To address the challenges of low carbon oxidation activity and low carbon utilization, a highly efficient, 3D solid-state architected anode is developed to enhance the performance of DCFCs below 600 °C. The cell with the 3D textile anode framework, Gd:CeO2 -Li/Na2 CO3 composite electrolyte, and Sm0.5 Sr0.5 CoO3 cathode demonstrates excellent performance with maximum power densities of 143, 196, and 325 mW cm-2 at 500, 550, and 600 °C, respectively. At 500 °C, the cells can be operated steadily with a rated power density of ≈0.13 W cm-2 at a constant current density of 0.15 A cm-2 with a carbon utilization over 85.5%. These results, for the first time, demonstrate the feasibility of directly electrochemical oxidation of solid carbon at 500-600 °C, representing a promising strategy in developing high-performing fuel cells and other electrochemical systems via the integration of 3D architected electrodes.

Bioinspired, Graphene/Al2O3 Doubly Reinforced Aluminum Composites with High Strength and Toughness.

Nacre, commonly referred to as nature's armor, has served as a blueprint for engineering stronger and tougher bioinspired materials. Nature organizes a brick-and-mortar-like architecture in nacre, with hard bricks of aragonite sandwiched with soft biopolymer layers. However, cloning nacre's entire reinforcing mechanisms in engineered materials remains a challenge. In this study, we employed hybrid graphene/Al2O3 platelets with surface nanointerlocks as hard bricks for primary load bearer and mechanical interlocking, along with aluminum laminates as soft mortar for load distribution and energy dissipation, to replicate nacre's architecture and reinforcing effects in aluminum composites. Compared with aluminum, the bioinspired, graphene/Al2O3 doubly reinforced aluminum composite demonstrated an exceptional, joint improvement in hardness (210%), strength (223%), stiffness (78%), and toughness (30%), which are even superior over nacre. This design strategy and model material system should guide the synthesis of bioinspired materials to achieve exceptionally high strength and toughness.

Capillarity Composited Recycled Paper/Graphene Scaffold for Lithium-Sulfur Batteries with Enhanced Capacity and Extended Lifespan.

An effective strategy to tackle the twin crises of global deforestation and fossil fuel depletion is to recycle biomass materials for energy storage devices. This study reports a unique and innovative solution to capitalize on a currently overlooked resource to produce high-performance lithium-sulfur (Li-S) batteries from recycled paper. The recycled paper fibers are creatively composited with graphene oxide sheets via a capillary adsorption method. The recycled paper/graphene oxide hybrid is then converted to activated paper carbon/reduced graphene oxide (APC/graphene) scaffold for sulfur infiltration. The assembled Li-APC/graphene/S battery exhibits a superior lifespan of 620 cycles with an excellent capacity retention rate of 60.5%. An APC interlayer is sandwiched between the Li anode and the separator to suppress the degradation of Li anode by preventing the nonhomogeneous growth of mossy Li whiskers, stretching the battery lifespan up to 1000 cycles with a capacitance retention rate of 52.3%. The capillary adsorption method coupled with the porous carbonaceous anode interlayer configuration creates a new opportunity for the development of batteries derived from porous biomass materials.

Effect of Taijiquan practice versus wellness education on knee proprioception in patients with knee osteoarthritis: a randomized controlled trial.

OBJECTIVE: To determine the effects of Taijiquan practice on knee proprioception in patients with knee osteoarthritis (OA). METHODS: We conducted a randomized controlled trial comparing Taijiquan with a control condition (wellness education) in patients with knee OA. The patients participated in either a 60-min Taijiquan session three times weekly or a 60-min weekly educational session, for 24 consecutive weeks. The primary outcomes were changes in knee proprioception. Secondary outcomes were changes in the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). RESULTS: After 24 weeks, compared with the control group, the Taijiquan group demonstrated better improvements in the joint position sense in knee flexion (left: -2.12?; right: -2.02?), and knee extension (left: -2.22?; right: -1.54?). In addition, the Taijiquan group showed significantly greater improvements in the WOMAC scores (P < 0.05) for knee pain (left: -3.17 points; right: -3.74 points), stiffness (left: -2.43 points; right: -2.13 points), and physical function (left: －10.99 points; right: －8.00 points), compared with the control group. CONCLUSION: A 24-week Taijiquan practice resulted in a significant improvement in knee proprioception in patients with knee OA. The present findings add increasing evidence regarding the clinical benefits of Taijiquan as a therapeutic modality for patients to improve the reflex protection of knee joints against potentially harmful forces.

Cotton-textile-enabled flexible self-sustaining power packs via roll-to-roll fabrication.

With rising energy concerns, efficient energy conversion and storage devices are required to provide a sustainable, green energy supply. Solar cells hold promise as energy conversion devices due to their utilization of readily accessible solar energy; however, the output of solar cells can be non-continuous and unstable. Therefore, it is necessary to combine solar cells with compatible energy storage devices to realize a stable power supply. To this end, supercapacitors, highly efficient energy storage devices, can be integrated with solar cells to mitigate the power fluctuations. Here, we report on the development of a solar cell-supercapacitor hybrid device as a solution to this energy requirement. A high-performance, cotton-textile-enabled asymmetric supercapacitor is integrated with a flexible solar cell via a scalable roll-to-roll manufacturing approach to fabricate a self-sustaining power pack, demonstrating its potential to continuously power future electronic devices.

Effects of Tai Ji Quan training on gait kinematics in older Chinese women with knee osteoarthritis: A randomized controlled trial.

BACKGROUND: Although Tai Ji Quan has been shown to relieve pain and improve functional mobility in people with knee osteoarthritis (OA), little is known about its potential benefits on gait characteristics among older Chinese women who have a high prevalence of both radiographic and symptomatic knee OA. This study aims to assess the efficacy of a tailored Tai Ji Quan intervention on gait kinematics for older Chinese women with knee OA. METHODS: A randomized controlled trial involving 46 older women in Shanghai, China, with clinically diagnosed knee OA. Randomized (1:1) participants received either a 60 min Tai Ji Quan session (n = 23) 3 times weekly or a 60 min bi-weekly educational session (n = 23) for 24 weeks. Primary outcomes were changes in gait kinematic measures from baseline to 24 weeks. Secondary outcomes included changes in scores on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Short Physical Performance Battery (SPPB). RESULTS: After 24 weeks the Tai Ji Quan group demonstrated better performance in gait velocity (mean difference, 8.40 cm/s, p = 0.01), step length (mean difference, 3.52 cm, p = 0.004), initial contact angle (mean difference, 2.19°, p = 0.01), and maximal angle (mean difference, 2.61°, p = 0.003) of flexed knees during stance phase compared to the control group. In addition, the Tai Ji Quan group showed significant improvement in WOMAC scores (p < 0.01) (mean difference, -4.22 points in pain, p = 0.002; -2.41 points in stiffness, p < 0.001; -11.04 points in physical function, p = 0.006) and SPPB scores (mean difference, 1.22 points, p < 0.001). CONCLUSION: Among older Chinese women with knee OA, a tailored Tai Ji Quan intervention improved gait outcomes. The intervention also improved overall function as indexed by the WOMAC and SPPB. These results support the use of Tai Ji Quan for older Chinese adults with knee OA to both improve their functional mobility and reduce pain symptomatology.

Cotton-Textile-Enabled, Flexible Lithium-Ion Batteries with Enhanced Capacity and Extended Lifespan.

Activated cotton textile (ACT) with porous tubular fibers embedded with NiS2 nanobowls and wrapped with conductive graphene sheets (ACT/NiS2-graphene) was fabricated by a simple two-step heat treatment method. When used as a binder-free electrode, the ACT/NiS2-graphene electrode exhibited an exceptional electrochemical performance including ultrahigh initial discharge capacity (∼1710 mAh g(-1) at 0.01 C), magnificent rate performance (the discharge capacitance retained at ∼645 mAh g(-1) at 1 C after 100 cycles) and excellent cyclic stability (the discharge capacitance recovered to ∼1016 mAh g(-1) at 0.1 C after 400 cycles).