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Ceramic aerogels are promising materials for thermal insulation and protection under harsh environments. Yet current synthesis methods fail to provide an energy-, time-, and cost-effective route for high-throughput production and large-scale applications, especially for non-oxide ceramic aerogels. Here we reported a way to synthesize SiC aerogels within seconds and over liter scale, with a demonstrated throughput of ~16 L min-1 in a typical lab experiment. The key lies in renovated combustion synthesis and a fast expansion from powder reactants to aerogel products over 1000% in volume. The synthesis process is self-sustainable and requires minimal energy input. The product is very cheap, with an estimated price of ~$0.7 L-1 (~$7 kg-1). The obtained SiC aerogels have excellent thermo-mechanical properties, including low thermal conductivity, high elasticity, and damage tolerance. Our invention not only offers a practical pathway for large-scale applications of ceramic aerogels, but also calls for rethinking of combustion synthesis in one-step conversion from raw chemicals to bulk products ready for practical applications.
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The rate performance, power density, and energy efficiency of electrochemical devices are often limited by ionic conductivities in electrolyte and electrode materials. Framework Prussian blue analogs and dense niobium oxides have been identified as high-rate electrodes for sodium- and lithium-ion batteries, respectively, yet the origin of the extremely high solid-state Na+/Li+ transport is not fully understood. Of critical importance is the fact that their ultra-low activation energy and anomalous pre-exponent factor cannot be satisfactorily rationalized from conventional theory of solid-state diffusion in the crystal lattice. Here, assisted by density-functional-theory calculations, we argued that the true origin is a unique surface-like diffusion mechanism of the intercalation ions. In a surface-like migration event, a mobile ion moves along the channel wall via a low coordination number and low migration barrier experiencing minimal steric hindrance. It is similar to surface diffusion in the conventional picture and contrasts with lattice diffusion from one interstitial/vacancy site to another one with high coordination number, crowded saddle-point geometry and high migration barrier. We found that the shifting from solid-state lattice diffusion to surface-like diffusion is determined by the size difference between the mobile ion and the diffusion channel, and a lowest migration energy barrier can be reached by mediating the channel size. The analogy to gas diffusion in molecular sieves shall be discussed. Additionally, the effects of defects and crystal water in Prussian blue analogs were also discussed for better understanding their rate performances in experimental scenarios.
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Advanced lithium-ion batteries utilize high upper cut-off voltages up to 4.8 V versus lithium metal to reach extraordinary energy densities. Such a harsh environment challenges the cathode stability and requires the construction of robust cathode electrolyte interphases at their electrochemical interface. Inspired by carbonated beverages with supersaturated CO2, here, a surface modification strategy that produces effective passivation layer of low modulus from the weakest link, is proposed CO2 bubbles preferentially nucleate and grow at rough surfaces, which in oxide cathodes, are also the local regions offering fast degradation pathway. Metal ion exchange on carbonated layer assists the construction of highly elastic interface under the guidance of packing factor. This method enables surface reconstruction at both primary and secondary particle levels for various cathodes exemplified by high-voltage LiNi0.8Co0.1Mn0.1O2 (NCM811) and LiCoO2 (LCO). Remarkably, with ultra-high upper cut-off voltage of 4.8 V versus Li+/Li, over 235 mAh g-1 discharge capacity, and over 900 W h kg-1 discharge energy at cathode level, ≈90% capacity retention can be obtained for LiNi0.8Co0.1Mn0.1O2 over 100 cycles at 0.5 C with commercial carbonate electrolytes. This carbonated beverage chemistry is promising for constructing high-quality surface passivation in many extreme-condition applications beyond battery cathodes.
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Prostate cancer (PCa) has become a public health concern in elderly men due to an ever-increasing number of estimated cases. Unfortunately, the available treatments are unsatisfactory because of a lack of a durable response, especially in advanced disease states. Extracellular vesicles (EVs) are lipid-bilayer encircled nanoscale vesicles that carry numerous biomolecules (e.g., nucleic acids, proteins, and lipids), mediating the transfer of information. The past decade has witnessed a wide range of EV applications in both diagnostics and therapeutics. First, EV-based non-invasive liquid biopsies provide biomarkers in various clinical scenarios to guide treatment; EVs can facilitate the grading and staging of patients for appropriate treatment selection. Second, EVs play a pivotal role in pathophysiological processes via intercellular communication. Targeting key molecules involved in EV-mediated tumor progression (e.g., proliferation, angiogenesis, metastasis, immune escape, and drug resistance) is a potential approach for curbing PCa. Third, EVs are promising drug carriers. Naïve EVs from various sources and engineered EV-based drug delivery systems have paved the way for the development of new treatment modalities. This review discusses the recent advancements in the application of EV therapies and highlights EV-based functional materials as novel interventions for PCa.
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Solar-driven interfacial evaporation (SDIE) is a highly promising approach to achieve sustainable desalination and tackle the global freshwater crisis. Despite advancements in this field, achieving balanced thermal localization and salt resistance remains a challenge. Herein, the study presents a 3D hierarchical porous ceramic platform for SDIE applications. The utilized alumina foam ceramics (AFCs) exhibit remarkable corrosion resistance and chemical stability, ensuring a prolonged operational lifespan in seawater or brines. The millimeter-scale air-filled pores in AFCs prevent thermal losses through conduction with bulk water, resulting in heat-localized interfaces. The hydrophilic nature of macroporous AFC skeletons facilitates rapid water replenishment on the evaporating surface for effective salt-resistant desalination. Benefiting from its self-radiation adsorption and side-assisted evaporation capabilities, the AFC-based evaporators exhibit high indoor evaporation rates of 2.99 and 3.54 kg m-2 h-1 under one-sided and three-sided illumination under 1.0 sun, respectively. The AFC-based evaporator maintains a high evaporation rate of ≈2.77 kg m-2 h-1 throughout the 21-day long-term test. Furthermore, it achieves a daily water productivity of ≈10.44 kg m-2 in outdoor operations. This work demonstrates the potential of 3D hierarchical porous ceramics in addressing the trade-off between heat localization and salt resistance, and contributes to the development of durable solar steam generators.
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Advanced ceramic materials and devices call for better reliability and damage tolerance. In addition to their strong bonding nature, there are examples demonstrating superior mechanical properties of nanostructure ceramics, such as damage-tolerant ceramic aerogels that can withstand high deformation without cracking and local plasticity in dense nanocrystalline ceramics. The recent progresses shall be reviewed in this perspective article. Three topics including highly elastic nano-fibrous ceramic aerogels, load-bearing nanoceramics with improved mechanical properties, and implementing machine learning-assisted simulations toolbox in understanding the relationship among structure, deformation mechanisms, and microstructure-properties shall be discussed. It is hoped that the perspectives present here can help the discovery, synthesis, and processing of future structural ceramic materials that are insensitive to processing flaws and local damages in service.
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Aqueous zinc-ion batteries are promising due to inherent safety, low cost, low toxicity, and high volumetric capacity. However, issues of dendrites and side reactions between zinc metal anode and the electrolyte need to be solved for extended storage and cycle life. Here, we proposed that an electrolyte additive with an intermediate chelation strength of zinc ion-strong enough to exclude water molecules from the zinc metal-electrolyte interface and not too strong to cause a significant energy barrier for zinc ion dissociation-can benefit the electrochemical stability by suppressing hydrogen evolution reaction, overpotential growth, and dendrite formation. Penta-sodium diethylene-triaminepentaacetic acid salt was selected for such a purpose. It has a suitable chelating ability in aqueous solutions to adjust solvation sheath and can be readily polarized under electrical loading conditions to further improve the passivation. Zn||Zn symmetric cells can be stably operated over 3500 h at 1 mA cm-2. Zn||NH4V4O10 full cells with the additive show great cycling stability with 84.6% capacity retention after 500 cycles at 1 A g-1. Since the additive not only reduces H2 evolution and corrosion but also modifies Zn2+ diffusion and deposition, highlyreversible Zn electrodes can be achieved as verified by the experimental results. Our work offers a practical approach to the logical design of reliable electrolytes for high-performance aqueous batteries.
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Aqueous rechargeable zinc-ion batteries (ARZIBs) are a promising next-generation energy-storage device by virtue of the superior safety and low cost of both the aqueous electrolyte and zinc-metal anode. However, their development is hindered by the lack of suitable cathodes with high volumetric capacity that can provide both lightweight and compact size. Herein, a novel cathode chemistry based on amorphous Se doped with transition metal Ru that mitigates the resistive surface layer produced by the side reactions between the Se cathode and aqueous electrolyte is reported. This improvement can permit high volumetric capacity in this system. Distinct from the conventional conversion mechanisms between Se and ZnSe in Se||Zn cells, this strategy realizes synchronous proton and Zn2+ intercalation/deintercalation in the Ru-doped amorphous Se||Zn half cells. Moreover, an unanticipated Zn2+ deposition/stripping process in this system further contributes to the superior electrochemical performance of this new cathode chemistry. Consequently, the Ru-doped amorphous Se||Zn half cells are found to deliver a record-high capacity of 721 mAh g-1 /3472 mAh cm-3 , and superior cycling stability of over 800 cycles with only 0.015% capacity decay per cycle. This reported work opens the door for new chemistries that can further improve the gravimetric and volumetric capacity of ARZIBs.
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Chemohormonal therapy is a standard treatment for metastatic hormone-sensitive prostate cancer (mHSPC); however, there are no biomarkers to guide clinical decisions regarding therapeutic options. We aimed to evaluate the clinical utility of serial circulating tumor DNA (ctDNA) sequencing in early prediction of the efficacy of chemohormonal therapy in patients with mHSPC. We conducted a retrospective observational study of 66 patients with mHSPC receiving chemohormonal therapy who underwent serial targeted gene-panel ctDNA sequencing. Peripheral blood samples were collected before treatment and after one cycle of chemotherapy. Kaplan-Meier and log-rank analyses were used to analyze the association between ctDNA status and disease progression-free survival. Serial changes in the ctDNA fraction and genetic alterations were also observed. After one cycle of chemotherapy, 23 (34.8%) patients displayed elevated ctDNA levels, whereas the other patients (65.2%, n = 43) did not. The median time to castration resistance in the group with reduced ctDNA levels was significantly longer than that in the group with increased ctDNA levels (17.70 vs. 8.43 months [mo], p < 0.001). Interestingly, patients with de novo alterations in homologous recombination pathway genes after treatment experienced a shorter time to castration resistance than that experienced by the remaining patients (8.02 vs. 13.20 mo, p = 0.011). The increased ctDNA levels or de novo alterations detected in homologous recombination pathway genes are a harbinger of disease progression. Early serial ctDNA sequencing could aid clinicians in making accurate treatment decisions.
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BACKGROUND: The precise staging and proper management of high-risk prostate cancer (PCa) continues to be a challenge. We aimed to demonstrate the prognostic value of baseline prostate-specific membrane antigen-ligand positron emission tomography/computed tomography (PSMA-PET/CT) in high-risk, nonmetastatic PCa patients who received neoadjuvant hormonal or chemohormonal treatment followed by radical prostatectomy (RP). METHODS: We performed retrospective analyses of 70 patients with high-risk, nonmetastatic PCa confirmed by biopsy between 2018 and 2021. All patients underwent neoadjuvant therapy followed by RP and pelvic lymph node dissection (PLND); PSMA-PET/CT was performed before initiation of neoadjuvant therapy. Acquired image information and clinical characteristics/outcomes were examined for possible associations. RESULTS: Among 70 high-risk PCa patients, median age was 69 years old and median prostate specific antigen (PSA) at presentation was 58.5 ng/mL. Thirty (42.9%) patients had uptake of the PSMA tracer only in the primary PCa lesions and 40 (57.1%) patients had PSMA-positive lesions in regional or distant sites. Sixteen (32%) localized PCa patients defined by pre-PET magnetic resonance imaging were found to have locally advanced PCa based on PSMA-PET/CT. Fifteen (30%) localized PCa patients and 7 (35%) locally advanced PCa patients were upstaged to metastatic PCa. The sensitivity and specificity of PSMA-PET/CT for the detection of lymph node involvement were 90.9% and 69.5%, respectively, with a positive prediction value of 35.7% and negative prediction value of 97.6%. The diagnostic accuracy was 72.9%. Univariate analysis showed upstaging, tumor stage, and metastasis location based on PSMA-PET/CT are predictors to PSA persistence after surgery, while multivariate logistic regression analysis showed only the tumor stage based on PSMA-PET/CT remained an independent predictor of the outcome. CONCLUSIONS: This study further highlights the accuracy and necessity of PSMA-PET/CT in newly diagnosed, high-risk, nonmetastatic PCa patients.
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Antígeno Prostático Específico , Neoplasias da Próstata , Masculino , Humanos , Idoso , Próstata/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Terapia Neoadjuvante , Estudos Retrospectivos , Radioisótopos de Gálio , Metástase Linfática/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , ProstatectomiaRESUMO
Garnet oxides such as Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO) are promising solid electrolyte materials for all-solid-state lithium-metal batteries because of high ionic conductivity, low electronic leakage, and wide electrochemical stability window. While LLZTO has been frequently discussed to be stable against lithium metal anode, it is challenging to achieve and maintain good solid-on-solid wetting at the metal/ceramic interface in both processing and extended electrochemical cycling. Here we address the challenge by a powder-form magnesium nitride additive, which reacts with the lithium metal anode to produce well-dispersed lithium nitride. The in situ formed lithium nitride promotes reactive wetting at the Li/LLZTO interface, which lowers interfacial resistance, increases critical current density (CCD), and improves cycling stability of the electrochemical cells. The additive recipe has been diversified to titanium nitride, zirconium nitride, tantalum nitride, and niobium nitride, thus supporting the general concept of reactive dispersion-plus-wetting. Such a design can be extended to other solid-state devices for better functioning and extended cycle life.
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High-capacity metal oxides based on non-toxic earth-abundant elements offer unique opportunities as advanced anodes for lithium-ion batteries (LIBs). But they often suffer from large volumetric expansion, particle pulverization, extensive side reactions, and fast degradations during cycling. Here, an easy synthesis method is reported to construct amorphous borate coating network, which stabilizes conversion-type iron oxide anode for the high-energy-density semi-solid-state bipolar LIBs. The nano-borate coated iron oxide anode has high tap density (1.6 g cm-3 ), high capacity (710 mAh g-1 between 0.5 - 3.0 V, vs Li/Li+ ), good rate performance (200 mAh g-1 at 50 C), and excellent cycling stability (≈100% capacity resention over 1,000 cycles at 5 A g-1 ). When paired with high-voltage cathode LiCoO2 , it enables Cu current collector-free pouch-type classic and bipolar full cells with high voltage (7.6 V with two stack layers), achieving high energy density (≈350 Wh kg-1 ), outstanding power density (≈6,700 W kg-1 ), and extended cycle life (75% capacity retention after 2,000 cycles at 2 C), superior to the state-of-the-art high-power LIBs using Li4 Ti5 O12 anode. The design and methodology of the nanoscale polyanion-like coating can be applied to other metal oxides electrode materials, as well as other electrochemical materials and devices.
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Aqueous zinc-ion batteries (ZIBs) are promising energy storage solutions with low cost and superior safety, but they suffer from chemical and electrochemical degradations closely related to the electrolyte. Here, a new zinc salt design and a drop-in solution for long cycle-life aqueous ZIBs are reported. The salt Zn(BBI)2 with a rationally designed anion group, N-(benzenesulfonyl)benzenesulfonamide (BBI- ), has a special amphiphilic molecular structure, which combines the benefits of hydrophilic and hydrophobic groups to properly tune the solubility and interfacial condition. This new zinc salt does not contain fluorine and is synthesized via a high-yield and low-cost method. It is shown that 1 m Zn(BBI)2 aqueous electrolyte with a widened cathodic stability window effectively stabilizes Zn metal/H2 O interface, mitigates chemical and electrochemical degradations, and enables both symmetric and full cells using a zinc-metal electrode.
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Recent progress in high-energy-density oxide cathodes for lithium-ion batteries has pushed the limits of lithium usage and accessible redox couples. It often invokes hybrid anion- and cation-redox (HACR), with exotic valence states such as oxidized oxygen ions under high voltages. Electrochemical cycling under such extreme conditions over an extended period can trigger various forms of chemical, electrochemical, mechanical, and microstructural degradations, which shorten the battery life and cause safety issues. Mitigation strategies require an in-depth understanding of the underlying mechanisms. Here we offer a systematic overview of the functions, instabilities, and peculiar materials behaviors of the oxide cathodes. We note unusual anion and cation mobilities caused by high-voltage charging and exotic valences. It explains the extensive lattice reconstructions at room temperature in both good (plasticity and self-healing) and bad (phase change, corrosion, and damage) senses, with intriguing electrochemomechanical coupling. The insights are critical to the understanding of the unusual self-healing phenomena in ceramics (e.g., grain boundary sliding and lattice microcrack healing) and to novel cathode designs and degradation mitigations (e.g., suppressing stress-corrosion cracking and constructing reactively wetted cathode coating). Such mixed ionic-electronic conducting, electrochemically active oxides can be thought of as almost "metalized" if at voltages far from the open-circuit voltage, thus differing significantly from the highly insulating ionic materials in electronic transport and mechanical behaviors. These characteristics should be better understood and exploited for high-performance energy storage, electrocatalysis, and other emerging applications.
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Ultrafine-grained (UFG) refractory metals are promising materials for applications in aerospace, microelectronics, nuclear energy, and many others under extreme environments. Powder metallurgy (PM) allows to produce such materials with well-controlled chemistry and microstructure at multiple length scales and near-net shape manufacturing. However, sintering refractory metals to full density while maintaining a fine microstructure is still challenging due to the high sintering temperature and the difficulty to separate the kinetics of densification versus grain growth. Here an overview of the sintering issues, microstructural design rules, and PM practices towards UFG and nanocrystalline refractory metals are sought to be provided. The previous efforts shall be reviewed to address the processing challenges, including the use of fine/nanopowders, second-phase grain growth inhibitors, and field-assisted sintering techniques. Recently, pressureless two-step sintering has been successfully demonstrated in producing dense UFG refractory metals down to ≈300 nm average grain size with a uniform microstructure and this technological breakthrough shall be reviewed. PM progresses in specific materials systems shall be next reviewed, including elementary metals (W and Mo), refractory alloys (W-Re), refractory high-entropy alloys, and their composites. Last, future developments and the endeavor towards UFG and nanocrystalline refractory metals with exceptionally uniform microstructure and improved properties are outlined.
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Management and treatment of terminal metastatic castration-resistant prostate cancer (mCRPC) remains heavily debated. We sought to investigate the efficacy of programmed cell death 1 (PD-1) inhibitor plus anlotinib as a potential solution for terminal mCRPC and further evaluate the association of genomic characteristics with efficacy outcomes. We conducted a retrospective real-world study of 25 mCRPC patients who received PD-1 inhibitor plus anlotinib after the progression to standard treatments. The clinical information was extracted from the electronic medical records and 22 patients had targeted circulating tumor DNA (ctDNA) next-generation sequencing. Statistical analysis showed that 6 (24.0%) patients experienced prostate-specific antigen (PSA) response and 11 (44.0%) patients experienced PSA reduction. The relationship between ctDNA findings and outcomes was also analyzed. DNA-damage repair (DDR) pathways and homologous recombination repair (HRR) pathway defects indicated a comparatively longer PSA-progression-free survival (PSA-PFS; 2.5 months vs 1.2 months, P = 0.027; 3.3 months vs 1.2 months, P = 0.017; respectively). This study introduces the PD-1 inhibitor plus anlotinib as a late-line therapeutic strategy for terminal mCRPC. PD-1 inhibitor plus anlotinib may be a new treatment choice for terminal mCRPC patients with DDR or HRR pathway defects and requires further investigation.
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Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Resultado do Tratamento , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Estudos RetrospectivosRESUMO
The primary challenge for efficient H2 evolution and hydrogen energy conversion is to develop highly active and stable catalysts with simple and reliable preparation processes. In this regard, we have designed and synthesized a porous carbon-supported low-Pt alloy catalyst (Pt3Co/Co@C composite) using ZIF-67 as a template. It showed uniformly dispersed Pt3Co/Co on the porous carbon layer due to the confinement effect of the porous carbon layer. Pt3Co/Co@C demonstrated excellent activity for the hydrogen evolution reaction in the full pH range, with an overpotential of 187 mV in 0.5 M H2SO4 to attain 100 mA/cm2 as well as long-term stability. It also displayed superior mass activity for the oxygen reduction reaction (ORR) at 0.85 V (vs RHE) compared to the commercial Pt/C. Furthermore, the Pt3Co/Co@C catalyst exclusively enabled a four-electron reaction process under ORR conditions without the competitive pathway to H2O2. The current work provides guidance for the design and facile synthesis of Pt-based catalysts with enhanced performance.
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Porous electrodes that conduct electrons, protons, and oxygen ions with dramatically expanded catalytic active sites can replace conventional electrodes with sluggish kinetics in protonic ceramic electrochemical cells. In this work, a strategy is utilized to promote triple conduction by facilitating proton conduction in praseodymium cobaltite perovskite through engineering non-equivalent B-site Ni/Co occupancy. Surface infrared spectroscopy is used to study the dehydration behavior, which proves the existence of protons in the perovskite lattice. The proton mobility and proton stability are investigated by hydrogen/deuterium (H/D) isotope exchange and temperature-programmed desorption. It is observed that the increased nickel replacement on the B-site has a positive impact on proton defect stability, catalytic activity, and electrochemical performance. This doping strategy is demonstrated to be a promising pathway to increase catalytic activity toward the oxygen reduction and water splitting reactions. The chosen PrNi0.7 Co0.3 O3- δ oxygen electrode demonstrates excellent full-cell performance with high electrolysis current density of -1.48 A cm-2 at 1.3 V and a peak fuel-cell power density of 0.95 W cm-2 at 600 °C and also enables lower-temperature operations down to 350 °C, and superior long-term durability.
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Protonic ceramic electrochemical cells hold promise for operation below 600 °C (refs. 1,2). Although the high proton conductivity of the bulk electrolyte has been demonstrated, it cannot be fully used in electrochemical full cells because of unknown causes3. Here we show that these problems arise from poor contacts between the low-temperature processed oxygen electrode-electrolyte interface. We demonstrate that a simple acid treatment can effectively rejuvenate the high-temperature annealed electrolyte surface, resulting in reactive bonding between the oxygen electrode and the electrolyte and improved electrochemical performance and stability. This enables exceptional protonic ceramic fuel-cell performance down to 350 °C, with peak power densities of 1.6 W cm-2 at 600 °C, 650 mW cm-2 at 450 °C and 300 mW cm-2 at 350 °C, as well as stable electrolysis operations with current densities above 3.9 A cm-2 at 1.4 V and 600 °C. Our work highlights the critical role of interfacial engineering in ceramic electrochemical devices and offers new understanding and practices for sustainable energy infrastructures.
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Proton conduction underlies many important electrochemical technologies. A family of new proton electrolytes is reported: acid-in-clay electrolyte (AiCE) prepared by integrating fast proton carriers in a natural phyllosilicate clay network, which can be made into thin-film (tens of micrometers) fluid-impervious membranes. The chosen example systems (sepiolite-phosphoric acid) rank top among the solid proton conductors in terms of proton conductivities (15 mS cm-1 at 25 °C, 0.023 mS cm-1 at -82 °C), electrochemical stability window (3.35 V), and reduced chemical reactivity. A proton battery is assembled using AiCE as the solid electrolyte membrane. Benefitting from the wider electrochemical stability window, reduced corrosivity, and excellent ionic selectivity of AiCE, the two main problems (gassing and cyclability) of proton batteries are successfully solved. This work draws attention to the element cross-over problem in proton batteries and the generic "acid-in-clay" solid electrolyte approach with superfast proton transport, outstanding selectivity, and improved stability for room- to cryogenic-temperature protonic applications.