Herein, we developed a partially controlled pyrolysis strategy to create evenly distributed NiO nanoparticles within NiFe‐MOF nanosheets (MOF NSs) for electrochemical synthesis of H2O2 by a ...two‐electron oxygen reduction reaction (ORR). The elemental Ni can be partially transformed to NiO and uniformly distributed on the surface of the MOF NSs, which is crucial for the formation of the particular structure. The optimized MOF NSs‐300 exhibits the highest activity for ORR with near‐zero overpotential and excellent H2O2 selectivity (ca. 99 %) in 0.1 m KOH solution. A high‐yield H2O2 production rate of 6.5 mol gcat−1 h−1 has also been achieved by MOF NSs‐300 in 0.1 m KOH and at 0.6 V (vs. RHE). In contrast to completely pyrolyzed products, the enhanced catalytic activities of partially pyrolyzed MOF NSs‐300 originates mainly from the retained MOF structure and the newly generated NiO nanoparticles, forming the coordinatively unsaturated Ni atoms and tuning the performance towards electrochemical H2O2 synthesis.
A new class of partially pyrolyzed NiFe metal–organic framework nanosheets (MOF NSs) was created for the electrochemical synthesis of H2O2 by two‐electron oxygen reduction reaction (ORR) for the first time. The optimized MOF NSs‐300 exhibits the highest activity for ORR with near‐zero overpotential and excellent H2O2 selectivity (ca. 99 %) in 0.1 m KOH, outperforming most electrocatalysts reported to date.
•COVID-19 infection can lead to the development of systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome MODS within a few days of disease onset.•A powerful cytokine ...storm accompanies COVID-19 pneumonia.•The capacity to accurately predict and intervene in the cytokine storm during COVID-19 pneumonia, as well as the ability to design effective specific strategies to block excessive inflammation, is critical for patient survival.
Clinical intervention in patients with corona virus disease 2019 (COVID-19) has demonstrated a strong upregulation of cytokine production in patients who are critically ill with SARS-CoV2-induced pneumonia. In a retrospective study of 41 patients with COVID-19, most patients with SARS-CoV-2 infection developed mild symptoms, whereas some patients later developed aggravated disease symptoms, and eventually passed away because of multiple organ dysfunction syndrome (MODS), as a consequence of a severe cytokine storm. Guidelines for the diagnosis and treatment of SARS-CoV-2 infected pneumonia were first published January 30th, 2020; these guidelines recommended for the first time that cytokine monitoring should be applied in severely ill patients to reduce pneumonia related mortality. The cytokine storm observed in COVID-19 illness is also an important component of mortality in other viral diseases, including SARS, MERS and influenza. In view of the severe morbidity and mortality of COVID-19 pneumonia, we review the current understanding of treatment of human coronavirus infections from the perspective of a dysregulated cytokine and immune response.
Abstract Designing active and stable electrocatalysts with economic efficiency for acidic oxygen evolution reaction is essential for developing proton exchange membrane water electrolyzers. Herein, ...we report on a cobalt oxide incorporated with iridium single atoms (Ir-Co 3 O 4 ), prepared by a mechanochemical approach. Operando X-ray absorption spectroscopy reveals that Ir atoms are partially oxidized to active Ir >4+ during the reaction, meanwhile Ir and Co atoms with their bridged electrophilic O ligands acting as active sites, are jointly responsible for the enhanced performance. Theoretical calculations further disclose the isolated Ir atoms can effectively boost the electronic conductivity and optimize the energy barrier. As a result, Ir-Co 3 O 4 exhibits significantly higher mass activity and turnover frequency than those of benchmark IrO 2 in acidic conditions. Moreover, the catalyst preparation can be easily scaled up to gram-level per batch. The present approach highlights the concept of constructing single noble metal atoms incorporated cost-effective metal oxides catalysts for practical applications.
Heterojunction nanostructures usually exhibit enhanced properties in compariosn with their building blocks and are promising catalyst candidates due to their combined surface and unique interface. ...Here, for the first time we realized the oriented growth of ultrasmall metal nanoparticles (NPs) on metal–organic framework nanosheets (MOF NSs) by precisely regulating the reduction kinetics of metal ions with solvents. In particular, a rapid reduction of metal ions leads to the random distribution of metal NPs on the surface of MOF NSs, while a slow reduction of metal ions results in the oriented growth of NPs on the edge of MOF NSs. Impressively, the strong synergy between Pt NPs and MOF NSs significantly enhances the hydrogen evolution reaction (HER) performance, and the optimal catalyst displays HER activities superior to those of a composite with a random growth of Pt NPs and commercial Pt/C under both acidic and alkaline conditions. Moreover, the versatility of such oriented growth has been extended to other metal NPs, such as Pd, Ag, and Au. We believe this work will promote research interest in material design for many potential applications.
Efficient electrocatalysts for hydrogen evolution reaction are key to realize clean hydrogen production through water splitting. As an important family of functional materials, transition metal ...oxides are generally believed inactive towards hydrogen evolution reaction, although many of them show high activity for oxygen evolution reaction. Here we report the remarkable electrocatalytic activity for hydrogen evolution reaction of a layered metal oxide, Ruddlesden-Popper-type Sr
RuO
with alternative perovskite layer and rock-salt SrO layer, in an alkaline solution, which is comparable to those of the best electrocatalysts ever reported. By theoretical calculations, such excellent activity is attributed mainly to an unusual synergistic effect in the layered structure, whereby the (001) SrO-terminated surface cleaved in rock-salt layer facilitates a barrier-free water dissociation while the active apical oxygen site in perovskite layer promotes favorable hydrogen adsorption and evolution. Moreover, the activity of such layered oxide can be further improved by electrochemistry-induced activation.
Abstract
The space charge layer (SCL) is generally considered one of the origins of the sluggish interfacial lithium-ion transport in all-solid-state lithium-ion batteries (ASSLIBs). However, in-situ ...visualization of the SCL effect on the interfacial lithium-ion transport in sulfide-based ASSLIBs is still a great challenge. Here, we directly observe the electrode/electrolyte interface lithium-ion accumulation resulting from the SCL by investigating the net-charge-density distribution across the high-voltage LiCoO
2
/argyrodite Li
6
PS
5
Cl interface using the in-situ differential phase contrast scanning transmission electron microscopy (DPC-STEM) technique. Moreover, we further demonstrate a built-in electric field and chemical potential coupling strategy to reduce the SCL formation and boost lithium-ion transport across the electrode/electrolyte interface by the in-situ DPC-STEM technique and finite element method simulations. Our findings will strikingly advance the fundamental scientific understanding of the SCL mechanism in ASSLIBs and shed light on rational electrode/electrolyte interface design for high-rate performance ASSLIBs.
Purpose/significance By quantitatively describing the research landscape of the discipline of library, information and archives management (LIAM), this paper can provide decision support for the ...establishment of cooperative relationships between institutions, thus promoting the development of inter-institutional cooperation. Method/process By using LDA model and network analysis method, this paper took 67 LIAM schools in China as an example. By thematic clustering of faculty's self-reported research interest texts, the similarity network of institutions was constructed, and community division and potential cooperative relationship mining were performed. Result/conclusion It is found that the current research interests of LIAM faculties in China mainly involve 11 topics, such as information resource management, informetrics and competitive intelligence, and information services and users. The sample schools can be divided into 7 communities, containing 457 pairs of potential cooperative relationships. In
Improving the catalytic efficiency of platinum for the hydrogen evolution reaction is valuable for water splitting technologies. Hydrogen spillover has emerged as a new strategy in designing ...binary-component Pt/support electrocatalysts. However, such binary catalysts often suffer from a long reaction pathway, undesirable interfacial barrier, and complicated synthetic processes. Here we report a single-phase complex oxide La
Sr
PtO
as a high-performance hydrogen evolution electrocatalyst in acidic media utilizing an atomic-scale hydrogen spillover effect between multifunctional catalytic sites. With insights from comprehensive experiments and theoretical calculations, the overall hydrogen evolution pathway proceeds along three steps: fast proton adsorption on O site, facile hydrogen migration from O site to Pt site via thermoneutral La-Pt bridge site serving as the mediator, and favorable H
desorption on Pt site. Benefiting from this catalytic process, the resulting La
Sr
PtO
exhibits a low overpotential of 13 mV at 10 mA cm
, a small Tafel slope of 22 mV dec
, an enhanced intrinsic activity, and a greater durability than commercial Pt black catalyst.
Triple-negative breast cancer (TNBC), representing ~15% of globally diagnosed breast cancer, is typically an incurable malignancy due to the lack of targetable surface targets for development of ...effective therapy. To address the unmet need for TNBC treatment, we recently determined that tissue factor (TF) is a useful surface target in 50-85% of patients with TNBC and developed a second-generation TF-targeting antibody-like immunoconjugate (called L-ICON) for preclinical treatment of TNBC. Using the chimeric antigen receptor (CAR) approach, here we develop and test TF-targeting CAR-engineered natural killer (TF-CAR-NK) cells that co-express CD16, the Fc receptor (FcγIII) to mediate antibody-dependent cellular toxicity (ADCC), for a preclinical assessment of immunotherapy of TNBC using TF-CAR-NK cell as single agent therapy and in combination with L-ICON. Our preclinical results demonstrate that TF-CAR-NK cells alone could kill TNBC cells and its efficacy was enhanced with L-ICON ADCC in vitro. Moreover, TF-CAR-NK cells were effective in vivo for the treatment of TNBC in cell line- and patient's tumor-derived xenograft mouse models. Thus, this study established the proof of concept of targeting TF as a new target in CAR-NK immunotherapy for effective treatment of TNBC and may warrant further preclinical study and potentially future investigation in TNBC patients.
Dielectric polymer composites with high dielectric constants and high thermal conductivity have many potential applications in modern electronic and electrical industry. In this study, three-phase ...composites comprising poly(vinylidene fluoride) (PVDF), barium titanate (BT) nanoparticles, and β-silicon carbide (β-SiC) whiskers were prepared. The superiority of this method is that, when compared with the two-phase PVDF/BT composites, three-phase composites not only show significantly increased dielectric constants but also have higher thermal conductivity. Our results show that the addition of 17.5 vol % β-SiC whiskers increases the dielectric constants of PVDF/BT nanocomposites from 39 to 325 at 1000 Hz, while the addition of 20.0 vol % β-SiC whiskers increases the thermal conductivity of PVDF/BT nanocomposites from 1.05 to 1.68 W m–1 K–1 at 25 °C. PVDF/β-SiC composites were also prepared for comparative research. It was found that PVDF/BT/β-SiC composites show much higher dielectric constants in comparison with the PVDF/β-SiC composites within 17.5 vol % β-SiC. The PVDF/β-SiC composites show dielectric constants comparable to those of the three-phase composites only when the β-SiC volume fraction is 20.0%, whereas the dielectric loss of the PVDF/β-SiC composites was much higher than that of the three-phase composites. The frequency dependence of the dielectric property for the composites was investigated by using broad-band (10–2–106 Hz) dielectric spectroscopy.
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