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The development of anode materials with high-rate capability is critical to high-power lithium batteries. T-Nb2O5 has been widely reported to exhibit pseudocapacitive behavior and fast lithium storage capability. However, the other polymorphs of Nb2O5 prepared at higher temperatures have the potential to achieve even higher specific capacity and tap density than T-Nb2O5, offering higher volumetric power and energy density. Here, micrometer-sized H-Nb2O5 with rich Wadsley planar defects (denoted as d-H-Nb2O5) is designed for fast lithium storage. The performance of H-Nb2O5 with local rearrangements of [NbO6] octahedra blocks surpasses that of T-Nb2O5 in terms of specific capacity, rate capability, and stability. A wide range variation in valence of niobium ions upon lithiation was observed for defective H-Nb2O5 via operando X-ray absorption spectroscopy. Operando extended X-ray absorption fine structure and ex-situ Raman spectroscopy reveals a large and reversible distortion of the structure in the two-phase region. Computation and ex-situ X-ray diffraction analysis reveals that the shear structure expands along major lithium diffusion pathways and contracts in the direction perpendicular to the shear plane. Planar defects relieve strain through perpendicular arrangements of blocks, minimizing volume change and enhancing structural stability. In addition, strong Li adsorption on planar defects enlarges intercalation capacity. Different from nanostructure engineering, our strategy to modify the planar defects in the bulk phase can effectively improve the intrinsic property. The findings in this work offer new insights into designing fast Li-ion storage materials in micrometer sizes through defect engineering, and the strategy is applicable to the material discovery for other energy-related applications.

To ensure safety and reduce the weight of vehicles, studies are being actively conducted on different aluminum alloys that have strength higher than conventional aluminum alloys. The development of high-performance aluminum alloys through magnesium content control is underway. Research on manufacturing techniques, such as, welding for application to the car body parts of these materials is required. In this study, the resistance spot weldability of an aluminum alloy with 6 wt.% magnesium (Al-6Mg) was evaluated and compared with the commercial aluminum alloy 5052, 6061 (Al5052, Al6061). The suitable welding range of the Al-6Mg was found to have a welding current of 24 kA to 28 kA, and a similar level of Al6061. The welding heat input was almost the same for the three materials, which resulted in no difference in the diameter of the nuggets. There was no significant difference of the porosity ratio between Al-6Mg and Al5052; however, the porosity ratio of Al6061 was higher. The alloy with the highest tensile shear strength, hardness and energy absorption of a welded joint was Al-6Mg. The low porosity ratio and high hardness of the Al-6Mg alloy caused the relatively high tensile shear strength and energy absorption of the welded joint.

We develop a solution-processable, Ag-sandwiched carbon-nanotube-coated, durable (SAND) architecture that enables power-efficient and highly consistent cyclic heating up to 400 °C at 6 V with neither structural degradation nor substrate breakage. The Ag/CNT/Ag-stacked SAND structure, comprising an airbrushed carbon nanotube (CNT) network layer sandwiched by the Ag layers reduced with ionic Ag ink coatings, can be created by a facile and scalable all-solution-processable fabrication protocol without resorting to vacuum-assisted nanofabrication. Through a systematic comparison with Ag-only and CNT/Ag- or Ag/CNT-bilayered structures, we show that the SAND architecture can improve the joule-heating efficiency and uniformity, and more importantly, the anti-breaking durability to overcome the thermal expansion discrepancy against the underlying substrate. This is analytically interpreted through a thermal stress-induced substrate breaking mechanism, where the increasing difference in the thermal expansion between the substrate and coated layers upon heating can be effectively suppressed within the SAND architecture. Readily applicable to more scalable, diverse substrates ranging from brittle glass to large-area polymer films, the SAND architecture can be utilized in the flexible and reliable anti-failure heating devices required in such applications as machine and vehicle components, sensor systems, and safety and warm-up gears.

Efficient transition metal oxide electrocatalysts for the alkaline hydrogen evolution reaction (HER) have received intensive attention to energy conversion but are limited by their sluggish water dissociation and unfavorable hydrogen migration and coupling. Herein, systematic density functional theory (DFT) predicts that on representative NiO, the hydroxylation (OH-) and heterointerface coupled with metallic Cu can respectively reduce the energy barrier of water dissociation and facilitate hydrogen spillover. Motivated by theoretical predictions, we subtly designed a delicate strategy to realize the electrochemical OH- modification in KOH with moderate concentration (HOM-NiO) and to channel rapid hydrogen spillover at the heterointerface of HOM-NiO and Cu, ensuring an enhanced HER kinetic. This HOM-NiO/Cu is systematically investigated by in situ XAS and electrochemical simulations, verifying its extraordinary merits for HER including the enhanced water dissociation, alleviated oxophilicity that is advantageous for consecutive adsorptions of water, and accelerated hydrogen spillover, thereby exhibiting superb HER activity with 33 and 310 mV overpotentials at the current densities of 10 and 1000 mA cm-2 in 1.0 M KOH, outperforming the Pt/C. This study might provide a reasonable strategy for the functionalized design of superior electrocatalysts.

The oxygen evolution reaction (OER) is a key reaction for many electrochemical devices. To date, many OER electrocatalysts function well in alkaline media, but exhibit poor performances in neutral and acidic media, especially the acidic stability. Herein, sodium-decorated amorphous/crystalline RuO 2 with rich oxygen vacancies (a/c-RuO 2 ) was developed as a pH-universal OER electrocatalyst. The a/c-RuO 2 shows remarkable resistance to acid corrosion and oxidation during OER, which leads to an extremely high catalytic stability, as confirmed by a negligible overpotential increase after continuously catalyzing OER for 60 h at pH = 1. Besides, a/c-RuO 2 also exhibits superior OER activities to commercial RuO 2 and most reported OER catalysts under all pH conditions. Theoretical calculations indicated that the introduction of Na dopant and oxygen vacancy in RuO 2 weakens the adsorption strength of the OER intermediates by engineering the d -band center, thereby lowering the energy barrier for OER.

Formamidinium lead triiodide (FAPbI3) perovskite solar cells (PSCs) are mainly fabricated by sequentially coating lead iodide and formamidinium iodide, or by coating a solution in which all components are dissolved in one solvent (one-pot process). The PSCs produced by both processes exhibited similar efficiencies; however, their long-term stabilities were notably different. We concluded that the major reason for this behaviour is the stabilization of the α-FAPbI3 phase by isopropylammonium cations produced by the chemical reaction between isopropyl alcohol, used as solvent, and methylammonium chloride, added during the process. On this basis, we fabricated PSCs by adding isopropylammonium chloride to the perovskite precursor solution for the one-pot process and achieved a certified power conversion efficiency of 23.9%. Long-term operational current density–voltage measurements (one sweep every 84 min under 1-Sun irradiation in nitrogen atmosphere) showed that the as-fabricated device with an initial efficiency of approximately 20% recorded an efficiency of about 23% after 1,000 h that gradually degraded to about 22% after an additional 1,000 h. The operational stability of formamidinium lead triiodide solar cells varies with the fabrication method of the perovskite layer. Now Park et al. find that isopropylammonium stabilizes the perovskite structure and leads to solar cells with 2,000-h stability under constant illumination.

Practically adapted physical integration of silicon and carbon predominates as a viable solution to realize high energy density batteries, however, the composite structure is vulnerable to fracture. Here we report a molecular-level mixed silicon-carbon composite anode through thermal pyrolysis of silane and subsequent mechanical mill, entailed by electrochemical dissociation and reclustering of such disordered silicon-carbon bonds during the cycles. Lithium insertion induces heterolytic fission of the bonds into sub-nanometre silicon particles segregated by redox-active carbon framework validated by microscopy analysis and reactive molecular dynamics simulation. The embedded structure with a high packing density of silicon prevents detrimental electrochemical coalescence and direct contact to a liquid electrolyte to stabilize the interfaces, while three-dimensional (3D) carbon framework buffers large volume expansion of silicon to enable an extended full battery cycling.

Rationally manipulating the in situ formed catalytically active surface of catalysts remains a tremendous challenge for a highly efficient water electrolysis. Here we present a cationic redox-tuning method to modulate in situ catalyst leaching and to redirect the dynamic surface restructuring of layered LiCoO2–xClx (x = 0, 0.1 or 0.2), for the electrochemical oxygen evolution reaction (OER). Chlorine doping lowered the potential to trigger in situ cobalt oxidation and lithium leaching, which induced the surface of LiCoO1.8Cl0.2 to transform into a self-terminated amorphous (oxy)hydroxide phase during the OER. In contrast, Cl-free LiCoO2 required higher electrochemical potentials to initiate the in situ surface reconstruction to spinel-type Li1±xCo2O4 and longer cycles to stabilize it. Surface-restructured LiCoO1.8Cl0.2 outperformed many state-of-the-art OER catalysts and demonstrated remarkable stability. This work makes a stride in modulating surface restructuring and in designing superior OER electrocatalysts via manipulating the in situ catalyst leaching. Rationally manipulating the in-situ-formed catalytically active surface of catalysts is a challenging but promising endeavour. Now, the surface of LiCoO2 during water oxidation is engineered by Cl doping via a cationic redox-tuning method that modulates in situ leaching and redirects the dynamic surface restructuring.

We report a facile synthesis of an Ir surface-enriched IrCo alloy catalyst and its excellent activity which outperforms commercial Pt/C for the hydrogen evolution reaction (HER) in acidic media showing fast kinetics. The as-synthesized catalyst exhibits low overpotentials of merely 9 mV and 29.3 mV to afford current densities of 10 and 100 mA cm−2, respectively, a turnover frequency of 1.25 s−1, a low Tafel slope of 23.7 mV dec−1, and stability for 100 h at a high current density of 100 mA cm−2 in 0.5 M H2SO4 electrolyte. Experiments and density functional theory (DFT) calculations indicate that the enrichment of Ir atoms on the outer surface of IrCo alloys is responsible for the effectively optimized free energy of hydrogen adsorption, which boosts the kinetics and HER performance. Our finding provides an insight into the metal surface enrichment on alloy nanoparticles (NPs).

Designing highly efficient, stable and low-cost bifunctional electrocatalysts based on in situ microstructure evolution, especially achieving partial lattice dislocation on a highly crystalline texture, to catalyze the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is challenging. Herein, catalysts with the Ni3Fe alloy embedded in Ni3FeN ultrathin nanosheets (∼1 nm) were fabricated through thermal ammonolysis treatment of cation-vacant monolayered NiFe layered double hydroxides. The emergence of the Ni3Fe alloy during the annealing process unavoidably leads to strain output to adjacent microstructures in ultrathin nanosheets, contributing to the formation of lattice dislocations. Such lattice defects, combining the ultrathin 2D morphology and synergistic interfacial effect between Ni3FeN and Ni3Fe, endow the electrocatalyst (d-Ni3FeN/Ni3Fe) with excellent electrocatalytic performance for both the OER and HER in alkaline media, requiring overpotentials of 250 mV and 125 mV to drive a current density of 10 mA cm−2 in 1 M KOH, respectively. The water electrolyzer with d-Ni3FeN/Ni3Fe as the cathode and anode yields a current density of 10 mA cm−2 at a low cell voltage of 1.61 V, and exhibits excellent durability of over 90 h, outperforming the commercial IrO2‖Pt/C cell. The present study offers a new trial of lattice defect engineering to develop high-performance non-precious bifunctional electrocatalysts for overall water splitting.

Designing a conductive amorphous buffer layer between crystals (or lowering the crystallinity of one component) to minimize lattice-strain influence between a highly crystalline substance and nearby constituents, thus ensuring good electronic structure towards multiphase synergistic electro-catalysis, is of tremendous importance for the construction of high-performance catalysts. Here, combining solvothermal and calcination strategies, oxygen vacancy-abundant amorphous MoO3 and non-crystal MoO2 were implanted into amorphous N,P-doped carbon as MoOx/NPC to hybridize sub-10 nm crystalline ruthenium dots (Ru-MoOx/NPC). Amorphous NPC bridges MoOx with Ru crystal to avoid the direct contact of MoOx and Ru, thus weakening the lattice strain influence. The electrochemical measurement results show that Ru-MoOx/NPC exhibits excellent catalytical capacity towards hydrogen evolution reaction (HER), which only needs overpotentials of 30 mV and 27 mV to deliver the current density of 10 mA cm−2 in alkaline and acid electrolytes, respectively, outperforming numerous recent-reported catalysts. Such superior HER activity can be attributed to structural advantages of abundant oxygen deficiency, small-sized Ru dots, conductive amorphous NPC, and weakened lattice-strain for the maximum protection of key components. This study not only presents a well-defined nanostructure with high HER activity but also offers insight into the weakening of lattice-strain effects to support the catalytical property.

Electronic coupling with the support plays a crucial role in boosting the intrinsic catalytic activity of a single-atom catalyst. Herein, the three-dimensional (3D) hierarchical Co(OH)F nanosheet arrays modified by single-atom Ru (SA-Ru/Co(OH)F) are prepared by a facile one-step hydrothermal method under mild conditions, which exhibit excellent activity with an overpotential of 200 and 326 mV at 10 and 500 mA cm−2, respectively, as well as robust stability for oxygen evolution reaction (OER) in 1.0 mol L−1 KOH electrolyte. The study of electronic structures and surface chemical states before and after OER testing reveals that the strong electronic coupling between single-atom Ru and Co(OH)F induces the charge redistribution in SA-Ru/Co(OH)F and suppresses the excessive oxidation of Ru into higher valence state (more than +4) under high OER potential. This work provides a strategy to stabilize single-atom Ru by Co(OH)F that can enhance the activity and durability for OER under large current densities.

Facilitating the dissociation of water and desorption of hydrogen are both crucial challenges for improving the hydrogen evolution reaction (HER) in alkaline media. Herein, we report the synthesis of heterostructure of Ru2 P/WO3 @NPC (N, P co-doped carbon) by a simple hydrothermal reaction using ruthenium and tungsten salts as precursors, followed by pyrolyzing under an Ar atmosphere. The Ru2 P/WO3 @NPC electrocatalyst exhibits an outstanding HER activity with an overpotential of 15 mV at a current density of 10 mA cm-2 and excellent durability in a 1.0 M KOH solution, outperforming state-of-the-art Pt/C and most reported electrocatalysts. Experimental results combined with density functional calculations reveal that the electron density redistribution in Ru2 P/WO3 @NPC is achieved by electron transfer from NPC to Ru2 P/WO3 and from Ru2 P to WO3 , which directly promotes the dissociation of water on W sites in WO3 and desorption of hydrogen on Ru sites in Ru2 P.

Inositol phosphate metabolism has emerged as one of the key players in synaptic transmission. Previous studies have shown that the deletion of inositol hexakisphosphate kinase 1 (IP6K1), which is responsible for inositol pyrophosphate biosynthesis, alters probability of presynaptic vesicle release and short-term facilitation of glutamatergic synapses in mouse hippocampus. However, the behavioral and cognitive functions regulated by IP6K1 remain largely elusive. In this study, IP6K1-knockout mice exhibited decreased prepulse inhibition with no defects in Y-maze and elevated plus maze tests. Interestingly, IP6K1 knockout led to impaired short-term memory formation in a contextual fear memory retrieval test with no effect on long-term memory. Further, both hippocampal long-term potentiation and long-term depression in IP6K1-knockout mice were similar to those in the wild-type control. Taken together, the findings in this study suggest the physiological roles of IP6K1 and the associated inositol pyrophosphate metabolism in regulating sensorimotor gating as well as short-term memory.

For the fabrication of perovskite solar cells (PSCs) using a solution process, it is essential to understand the characteristics of the perovskite precursor solution to achieve high performance and reproducibility. The colloids (iodoplumbates) in the perovskite precursors under various conditions were investigated by UV-visible absorption, dynamic light scattering, photoluminescence, and total internal reflection fluorescence microscopy techniques. Their local structure was examined by in situ X-ray absorption fine structure studies. Perovskite thin films on a substrate with precursor solutions were characterized by transmission electron microscopy, X-ray diffraction analysis, space-charge-limited current, and Kelvin probe force microscopy. The colloidal properties of the perovskite precursor solutions were found to be directly correlated with the defect concentration and crystallinity of the perovskite film. This work provides guidelines for controlling perovskite films by varying the precursor solution, making it possible to use colloid-engineered lead halide perovskite layers to fabricate efficient PSCs.

Particulate matter (PM)2.5 is a concern for public health nowadays. Although few studies have reported the skin diseases associated with PM2.5, its effects on keratinocytes have yet to be elucidated. The goal of this experiment was to analyze and identify the changes of gene expression in PM2.5-treated keratinocytes using RNA-sequencing (RNA-Seq) data. PM2.5-treated keratinocytes exhibited changes in cell cycle-related genes as well as genes involved in DNA replication, endoplasmic reticulum (ER) stress, intrinsic apoptosis, and immune response. A total of 669 genes showed changes in gene expression in PM2.5-treated keratinocytes, including 304 upregulated and 365 downregulated genes. Unlike other studies investigating skin disorders associated with PM2.5, our study found the mechanism of apoptosis suppression in keratinocytes. The findings may provide a novel insight into the management of chronic skin diseases in relation to PM2.5.

Designing efficient oxygen evolution reaction (OER) electrocatalysts based on single-atom catalysts is a highly promising option for cost-effective alkaline water electrolyzers. However, the instability of the OOH* intermediate and high energy barrier for the rate-determining step (RDS) (O* to OOH*) on the pure bimetallic-alloy represent serious challenges. Here, we report atomically dispersed Ru single-atoms on a cobalt–iron bimetallic-alloy encapsulated by graphitic carbon (RuSACoFe2/G) as an efficient and durable electrocatalyst for the alkaline OER. In-depth X-ray absorption spectroscopy (XAS) and aberration-corrected transmission electron microscopy (AC-TEM) along with theoretical calculations were employed to validate the isolated Ru sites in the surface-oxygen rich alloy. RuSACoFe2/G displays exceptional intrinsic activity, achieving a record low overpotential of only 180 mV at 10 mA cm−2 with superior durability in alkali media. Density functional theory (DFT) simulations revealed that the isolated Ru sites with pre-adsorbed surface oxygen species on a bimetallic-alloy efficiently stabilize the OOH* intermediate and significantly reduce the energy barrier for the RDS, boosting the intrinsic OER activity. Our integrated alkaline electrolyzer demands a low cell voltage of 1.48 V at 10 mA cm−2, suggesting that it has potential for use in practical applications.

Developing a highly efficient and cost-effective electrocatalyst for catalyzing the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is fundamentally important for the practical application of the overall water splitting technique. Herein, a bifunctional electrocatalyst constituted by FexNiy and CeO2 nanoparticles supported on the N-doped nanocarbon (NC) is fabricated by a simple one-pot pyrolysis of the homogeneous mixture of Fe, Ni, Ce nitrates and melamine. The synergistic effect of each component in the FexNiy/CeO2/NC gives rise to outstanding electrocatalytic activities and stability toward the HER and OER. For hydrogen evolution, the FexNiy/CeO2/NC shows a smaller overpotential of 260 mV to achieve a current density of 50 mA cm−2 in a 1 M KOH electrolyte. More significantly, a small overpotential of 240 mV for FexNiy/CeO2/NC affords an oxygen evolution current density of 10 mA cm−2, far lower than that of the benchmark IrO2. The practicability and electrocatalytic activity of the prepared FexNiy/CeO2/NC under practical operation conditions are also investigated. In particular, the FexNiy/CeO2/NC-based overall water splitting cell only needs a cell voltage of 1.70 V to output 10 mA cm−2 in alkaline electrolytes, comparable to that of the IrO2∥Pt/C cell. The present study may pioneer a new avenue for developing novel bifunctional electrocatalysts with high-performance and low cost for water splitting.

Developing low-cost and highly efficient electrocatalysts for overall water splitting is of far-reaching significance for new energy conversion. Herein, dual-cation Fe, Al-co-doped NiSe2 nanoparticles on reduced graphene oxide (Fe, Al-NiSe2/rGO) were prepared as a bifunctional electrocatalyst for overall water splitting. The dual-cation doping can induce a stronger electronic interaction between the foreign atoms and host catalyst, for optimizing the adsorption energy of reaction intermediates. Meanwhile, the leaching out of Al from the crystal structure of the target product during the alkaline wash creates more defects and increases the active site exposure. As a result, the Fe, Al-NiSe2/rGO catalyst exhibits excellent catalytic activities for both the OER and HER with an overpotential of 272 mV @η10 for the OER in 1.0 M KOH and 197 mV @η10 for the HER in 0.5 M H2SO4, respectively. A two-electrode electrolyzer using Fe, Al-NiSe2/rGO as the anode and cathode shows a low voltage of 1.70 V at the current density of 10 mA cm−2. This study emphasizes the synergistic contribution of the dual-cation co-doping effect and more defects created by Al leaching to boost the performance of water splitting.

The development of highly efficient and inexpensive catalysts is still a tremendous challenge for the electrocatalytic nitrogen reduction reaction (NRR), which is a promising alternative to high-temperature and high-pressure industrial technologies for the synthesis of NH3. Herein, we report a facile and large scale strategy exploiting a porous non-precious bimetallic oxide of NiWO4 for the NRR under ambient conditions. Benefiting from the above-mentioned merits, the designed electrocatalyst achieved outstanding catalytic activities in both 0.1 M HCl (NH3 yield: (40.05 ± 1.45) μg h−1 mg−1cat., Faraday efficiency (FE): (19.32 ± 0.68)% at −0.3 V) and 0.1 Na2SO4 (NH3 yield: (23.14 ± 1.75) μg h−1 mg−1cat., Farady efficiency: (10.18 ± 0.62)% at −0.3 V), and these efficiencies are superior to most of the reported non-precious metals for the NRR. Furthermore, the prepared catalyst presented excellent stability in both acidic and neutral media for up to 20 h. This work opens a constructive avenue for optimizing the catalytic performance of metal oxides and other transition metal-based catalysts for NRRs.

The poor catalyst stability in acidic oxidation evolution reaction (OER) has been a long-time issue. Herein, we introduce electron-deficient metal on semiconducting metal oxides-consisting of Ir (Rh, Au, Ru)-MoO3 embedded by graphitic carbon layers (IMO) using an electrospinning method. We systematically investigate IMO’s structure, electron transfer behaviors, and OER catalytic performance by combining experimental and theoretical studies. Remarkably, IMO with an electron-deficient metal surface (Irx+; x > 4) exhibit a low overpotential of only ~156 mV at 10 mA cm−2 and excellent durability in acidic media due to the high oxidation state of metal on MoO3. Furthermore, the proton dissociation pathway is suggested via surface oxygen serving as proton acceptors. This study suggests high stability with high catalytic performance in these materials by creating electron-deficient surfaces and provides a general, unique strategy for guiding the design of other metal-semiconductor nanocatalysts., The poor catalyst stability for oxygen evolution in acidic media has been a long-time issue. Here, authors demonstrate iridium on MoO3 exhibits a low overpotential for oxygen evolution and excellent durability in acidic media due to the high oxidation state of iridium metal on MoO3.

Skin barrier dysfunction induces skin inflammation. Signal transducer and activator of transcription 3 (STAT3) is known to be involved in Th17-mediated immune responses and barrier integrity in the cornea and intestine; however, its role in the skin barrier remains largely unknown. In this study, we elucidated the potential role of STAT3 in the skin barrier and its effect on kallikrein-related peptidase 5 (KLK5) and serine protease inhibitor Kazal-type 5 (SPINK5) expression using a mouse model with keratinocyte-specific ablation of STAT3. Keratinocyte-specific loss of STAT3 induced a cutaneous inflammatory phenotype with pruritus and intense scratching behaviour in mice. Transcriptomic analysis revealed that the genes associated with impaired skin barrier function, including KLK5, were upregulated. The effect of STAT3 on KLK5 expression in keratinocytes was not only substantiated by the increase in KLK5 expression following treatment with STAT3 siRNA but also by its decreased expression following STAT3 overexpression. Overexpression and IL-17A-mediated stimulation of STAT3 increased the expression of SPINK5, which was blocked by STAT3 siRNA. These results suggest that the expression of SPINK5 and KLK5 in keratinocytes could be dependent on STAT3 and that STAT3 might play an essential role in the maintenance of skin barrier homeostasis.

Metal–oxide interfaces provide a new opportunity to improve catalytic activity based on electronic and chemical interactions at the interface. Constructing a high density of interfaces is essential...

T cell-independent (TI) B cell response is critical for the early protection against pathogen invasion. The regulation and activation of Bruton’s tyrosine kinase (Btk) is known as a pivotal step of B cell antigen receptor (BCR) signaling in TI humoral immunity, as observed in patients with X-linked agammaglobulinemia (XLA) experiencing a high incidence of encapsulated bacterial infections. However, key questions remain as to whether a well-established canonical BCR signaling pathway is sufficient to regulate the activity of Btk. Here, we find that inositol hexakisphosphate (InsP(6)) acts as a physiological regulator of Btk in BCR signaling. Absence of higher order inositol phosphates (InsPs), inositol polyphosphates, leads to an inability to mount immune response against TI antigens. Interestingly, the significance of InsP(6)-mediated Btk regulation is more prominent in IgM(+) plasma cells. Hence, the present study identifies higher order InsPs as principal components of B cell activation upon TI antigen stimulation and presents a mechanism for InsP-mediated regulation of the BCR signaling.

Developing low-cost electrocatalysts to replace precious Ir-based materials is key for oxygen evolution reaction (OER). Here, we report atomically dispersed nickel coordinated with nitrogen and sulfur species in porous carbon nanosheets as an electrocatalyst exhibiting excellent activity and durability for OER with a low overpotential of 1.51 V at 10 mA cm−2 and a small Tafel slope of 45 mV dec−1 in alkaline media. Such electrocatalyst represents the best among all reported transition metal- and/or heteroatom-doped carbon electrocatalysts and is even superior to benchmark Ir/C. Theoretical and experimental results demonstrate that the well-dispersed molecular S|NiNx species act as active sites for catalyzing OER. The atomic structure of S|NiNx centers in the carbon matrix is clearly disclosed by aberration-corrected scanning transmission electron microscopy and synchrotron radiation X-ray absorption spectroscopy together with computational simulations. An integrated photoanode of nanocarbon on a Fe2O3 nanosheet array enables highly active solar-driven oxygen production., Water oxidation is considered the bottleneck reaction for light-driven water splitting due to the sluggish kinetics and poor stability. Here, authors show metal- and heteroatom-doped carbons as effective catalysts for both electrochemical and photoelectrochemical water splitting.

Manipulation of both pore diameters and heights of two-dimensional periodic porous polymer films is important to extensively control their characteristics. However, except for using different sized colloid templates in replication methods, an effective method that tunes these factors has rarely been reported. We found that both parameters are controllable by adjusting the flow behaviors of polystyrene colloids and curing resin precursors during the preparation of phenolic resin and poly(dimethylsiloxane) periodic porous films by embedding their precursors into colloidal crystal monolayers. We adjust the flow behaviors by either varying film preparation temperatures (≥glass transition temperature of polystyrene) or using the precursors mixed with different amounts of solvents that renders the colloids viscous. Consequently, the pore diameters and film heights change by 36-56 and 56-84%, respectively. Such modulation results in the change in height to diameter ratios and the areal fractions of resins at air-film interfaces, thereby significantly changing the water contact angles on these surfaces and their photonic characteristics. This straightforward method does not require additional steps, differently sized colloids, or different amounts of precursors for these parameter controls.

Hybridization with conductive nanospecies has attracted intense research interest as a general effective means to improve the photocatalytic functionalities of nanostructured materials. To establish universal design rules for high‐performance hybrid photocatalysts, correlations between versatile roles of conductive species and interfacial interaction between hybridized species are systematically investigated through fine‐control of intersheet distance between photocatalytically active TiO2 and metallic reduced graphene oxide (rGO)/RuO2 nanosheets. Molecular‐level tailoring of intersheet distance and electronic coupling between 2D nanosheets can be successfully achieved by restacking of colloidal nanosheet mixture with variable‐sized organic intercalants. While the shortest intersheet distance between restacked TiO2 and rGO nanosheets leads to the highest visible‐light‐driven photocatalytic activity, the best UV–vis photocatalyst performance occurs for moderate intersheet spacing. These results highlight the greater sensitivity of photoinduced electronic excitation to the intersheet distance than that of interfacial charge transfer. The rGO nanosheet can function as effective charge transport pathway and cocatalyst within ≈1.7 nm distance from the semiconducting nanosheet, and as efficient stabilizer for hybridized photocatalyst within ≈1.8 nm. The present study underscores that the intercalative restacking of colloidal nanosheet mixture with intercalants enables molecular‐level control of distance between 2D inorganic/graphene nanosheets, which provides a rational design strategy for high‐performance hybrid photocatalysts., Molecular‐level control of intersheet distance and electronic coupling between 2D graphene/inorganic nanosheets can be achieved by restacking colloidal nanosheet mixture with variable‐sized intercalants. The optimal conditions for the efficacy of conductive nanosheet as photosensitizer, electron reservoir, charge transport pathway, cocatalyst, and stabilizer can be established with restacked organic–semiconductor–conductor nanohybrids, providing novel rational design strategy for high‐performance hybrid photocatalysts.

Nitrogen-doped porous carbons containing atomically dispersed iron are prime candidates for substituting platinum-based catalysts for oxygen reduction reaction (ORR) in fuel cells. These carbon catalysts are classically synthesized via complicated routes involving multiple heat-treatment steps to form the desired Fe-Nx sites. We herein developed a highly active Fesingle bondNsingle bondC catalyst comprising of exclusive Fe-Nx sites by a simplified solid-state synthesis protocol involving only a single heat-treatment. Imidazole is pyrolyzed in the presence of an inorganic salt-melt resulting in highly porous carbon sheets decorated with abundant Fe-Nx centers, which yielded a high density of electrochemically accessible active sites (1.36 × 1019 sites g−1) as determined by the in situ nitrite stripping technique. The optimized catalyst delivered a remarkable ORR activity with a half-wave potential (E1/2) of 0.905 VRHE in alkaline electrolyte surpassing the benchmark Pt catalyst by 55 mV. In acidic electrolyte, an E1/2 of 0.760 VRHE is achieved at a low loading level (0.29 mg cm−2). In PEMFC tests, a current density of 2.3 mA cm−2 is achieved at 0.90 ViR-free under H2–O2 conditions, reflecting high kinetic activity of the optimized catalyst.

Hydrogen evolution reaction (HER) electrocatalysts over platinum (Pt) in an alkaline medium is crucial for hydrogen economy. Herein, we demonstrate new concept “interface-active electrode” to transform naturally inert alkaline HER materials towards industry-applicable HER electrocatalyst, comprised of interface-rich NiP2-FeP2 on Cu nanowires that required overpotential as low as 23.6 and 357 mV at -10 and -1000 mA/cm2, respectively, with exceptional stability at the industrial current density of -1 A cm-2, superior to commercial Pt under alkaline solution. Structural characterization and theoretical calculations revealed the abundant interface between facets of NiP2-FeP2 on Cu exhibits optimum H adsorption-free energy than Pt and lower kinetic barrier for water dissociation (ΔGB = 0.16 eV), boosting alkaline HER. Additionally, when integrated in a water splitting device, generated 10 mA/cm2 at only 1.42, 1.4, and 1.31 V under 1 M KOH, artificial seawater at 25 ̊C and 100 ̊C, respectively, along with high solar-to-hydrogen (STH) conversion efficiency of 19.85 %.

A critical role of bond competition in tailoring Mn valence state and bifunctional electrocatalyst activity of manganese oxide is evidenced by the remarkable improvement of the electrocatalyst activity of α-MnO2 upon the partial substitution of electronegative Ru4+ ion. The replacement of Mn4+ ion with more electronegative Ru4+ one is quite effective in weakening adjacent (Mn−O) bonds in terms of bond competition, leading to the stabilization of Jahn-Teller active Mn3+ species, as well as in providing electrocatalytically active Ru sites. The resulting Ru-substituted α-Mn1−xRuxO2 nanowires show much higher electrocatalyst activities for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) than does the physical mixture of α-MnO2 and RuO2, indicating the main role of (Mn−O) bond covalency in the optimization of the bifunctional electrocatalyst activity of manganese oxide. The present study underscores that, like the previous strategy of structural disorder enhancement, the substitution of highly electronegative cation can provide a novel efficient way of improving the electrocatalyst performance of manganese oxide via the bond competition between adjacent (Ru−O) and (Mn−O) bonds.

The microstructure and corrosion properties of as-cast AZ61 (Mg-6%Al-1%Zn) and AZ61 alloys doped with titanium and calcium and subjected to high ratio differential speed rolling were investigated. Addition of the alloying elements to the AZ61 alloy resulted in remarkable modification of the morphology and the amount of continuous β (Mg17Al12)-phase. Addition of Ti to the as-cast AZ61 alloy causes a decrease in the volume fraction (or discontinuity of the β-phase), leading to strong anodic dissolution. In contrast, addition of Ca to the as-cast AZ61 alloy is rather effective for preventing pitting corrosion. This is attributed to the formation of a semi-continuous network β-structure. The (Mg, Al)4Ca phases dispersed between the β (Mg17Al12)-phases led to continuity in the AZ61 alloy with Ca. The AZ61 and AZ61-X(Ca, Ti) alloys subjected to severe plastic deformation via high-ratio differential speed rolling possessed a nano-composite-like microstructure in which the α-Mg matrix with an ultra-fine grain was surrounded by a large number of fine β particles. These particles were either dynamically precipitated or broken at the grain boundaries, as well as in the grain interiors, by the high ratio differential speed rolling process. The corrosion resistance of the AZ61 and AZ61-X (X = Ca, Ti) alloys subjected to high ratio differential speed rolling was largely improved by the microstructural modification. The high ratio differential speed rolling process greatly influenced the texture of the Mg alloys, which significantly affected their corrosion behavior.

Lithium-excess 3d-transition-metal layered oxides (Li1+xNiyCozMn1−x−y−zO2, >250 mAh g−1) suffer from severe voltage decay upon cycling, which decreases energy density and hinders further research and development. Nevertheless, the lack of understanding on chemical and structural uniqueness of the material prevents the interpretation of internal degradation chemistry. Here, we discover a fundamental reason of the voltage decay phenomenon by comparing ordered and cation-disordered materials with a combination of X-ray absorption spectroscopy and transmission electron microscopy studies. The cation arrangement determines the transition metal-oxygen covalency and structural reversibility related to voltage decay. The identification of structural arrangement with de-lithiated oxygen-centred octahedron and interactions between octahedrons affecting the oxygen stability and transition metal mobility of layered oxide provides the insight into the degradation chemistry of cathode materials and a way to develop high-energy density electrodes., There is growing interest in the fundamental understanding of the voltage decay mechanism in Li-excess layered cathode materials. Here, the authors report a multilateral and macroscopic analysis that considers interaction between oxygen and atomic arrangement of Li1+xNiyCozMn1−x−y−zO2.

Thinner design of smart phone continuously would need to the high energy density lithium-ion batteries. Lithium-ion batteries are composed of four major component, cathode, anode, electrolyte and separator. Each components’s reaction by pyrolysis and interaction between components are causative of exothermic reaction of lithium ion batteries. We investigated causes of exothermic reaction of lithium ion batteries having thermal analysis, surface analysis and structure analysis by dismantling two kinds of 3.2Ah lithium-ion batteries composed of most commercialized LiCoO2 cathode material and Graphite anode material. In LiCoO2 cathode material, Li ions are oxidized by charge process, it exists as Li0.5CoO2. Near 230oC, structure of Li0.5CoO2 is changed, it causes exothermic reaction. EXAFS, structure analysis, showed change of two kind of Li0.5CoO2 structure according to temperature change. By investigating Co-Co and Co-O bond, we can find that structure stability as temperature increasing is different as status of LiCoO2 such as Mg doping. Surface analysis showed surface status of cathode material and distribution of anode SEI layer. Especially, in case of anode, Alkyl Carbonate is considered as important factor of thermal stability because it makes exothermic reactions as it decomposed. We identified how thick the alkyl carbonates were deposited and we found difference of exothermic value by DSC thermal analysis between two kinds of graphite of lithium ion batteries. These analysis data indicate which part is important for thermal stability and investigate exothermic reaction mechanism of Cell components. We made sure structure change of cathode material and distribution of Alkyl carbonate in anode SEI layer is important for thermal runaway of Cell. These results suggest improvement direction for increasing of thermal stability.

Strontium iridate perovskites are attractive electrocatalysts for acidic water oxidation, but suffer from serious Sr-leaching during catalysis, which causes surface rearrangements that damage long-term applications. Herein, 6H phase SrIrO3 modified with laminar Sr2IrO4 (SrIrO) have been developed. Unlike the previous extreme chemical state changes of Ir, SrIrO maintained relatively stable surface Ir states during electrocatalysis. The layered nature of Sr2IrO4 enables the interlaminar Sr easily extracted from the crystal while remaining the in-plane IrO6 octahedral framework, thereby stabilizing the Ir state. The SrIrO displays extremely low overpotential of 245 mV for OER and 18.2 mV for HER at 10 mA cm−2, and outstanding catalytic stability. For acidic water splitting, SrIrO requires only 1.50 V to achieve 10 mA cm−2, surpassing most reported electrocatalysts. This work offers a new route for alleviating the surface rearrangements of perovskites, and exploring efficient and stable electrocalysts for hydrogen production via electrochemical water electrolysis.

Ru nanoparticles (NPs) and single atoms (SAs)‐based materials have been investigated as alternative electrocatalysts to Pt/C for hydrogen evolution reaction (HER). Exploring the dominant role of atomic‐ and nano‐ruthenium as active sites in acidic and alkaline media is very necessary for optimizing the performance. Herein, an electrocatalyst containing both Ru SAs and NPs anchored on defective carbon (RuSA+NP/DC) has been synthesized via a Ru–alginate metal–organic supramolecules conversion method. RuSA+NP/DC exhibits low overpotentials of 16.6 and 18.8 mV at 10 mA cm−2 in acidic and alkaline electrolytes, respectively. Notably, its mass activities are dramatically improved, which are about 1.1 and 2.4 times those of Pt/C at an overpotential of 50 mV in acidic and alkaline media, respectively. Theoretical calculations reveal that Ru SAs own the most appropriate H* adsorption strength and thus, plays a dominant role for HER in acid electrolyte, while Ru NPs facilitate the dissociation of H2O that is the rate‐determining step in alkaline electrolyte, leading to a remarkable HER activity., Defective carbon anchored Ru single atoms (SAs) and nanoparticles (NPs) is prepared, and exhibits super hydrogen evolution reaction (HER) activity in both acidic and alkaline media. Theoretical calculations reveal that Ru SAs are inclined to adsorption of H* that is critical for acidic HER, and Ru NPs facilitate the dissociation of H2O that is the rate‐determining step in alkaline medium.

D-band-center control engineering, particularly combining both cation and anion intercalations towards heterostructure formation with simultaneous usage of Ru, N as well as F species, for optimal electronic structure as efficient hydrogen evolution reaction (HER) catalysts remains a daunting challenge but critical for renewable-energy technologies. Herein, we lay emphasis on the design of active-site electronic structure based on d-band-center shift through the construction of Co4N-CoF2 heterostructure coupled with Ru doping (Ru/Co4N-CoF2). Solvothermal coordination reaction followed by annealing course causes cooccurrence of F, N, Ru in Co neighborhood. As-obtained Ru/Co4N-CoF2 exhibits superior HER activity in alkaline electrolyte with overpotential as low as 53 mV to yield a current density of 10 mA cm−2 which is close to that of commercial Pt/C, outperforming many transition-metal-based catalysts recent-reported. Moreover, it still presents good durability with continuous operation of 22 h in 1.0 M KOH. Such excellent performance is ascribed to appropriate electron structure of Ru/Co4N-CoF2 for optimized hydrogen binding abilities on Co/Ru sites as confirmed by synchrotron-based X-ray adsorption near-edge structure and X-ray photoelectron spectroscopies. This study not only establishes highly active electrocatalysts by impacting d-band center of active sites but also provides valuable insights into the synergistic-effect protocol of doping and heterostructure strategies for d-band-center shifting.

In the paper results of the investigation of the thermal decomposition process of double complex salt [Pt(NH3)4][OsCl6] by x-ray absorption (XAFS) and photoelectron (XPS) spectroscopies have been presented. The data obtained allows a mechanism of the thermal decomposition to be refined. An influence of size effect and nanoalloy formation on chemical shift of Pt and Os is discussed.

Zn–air batteries suffer from the slow kinetics of oxygen reduction reaction (ORR) and/or oxygen evolution reaction (OER). Thus, the bifunctional electrocatalysts are required for the practical application of rechargeable Zn–air batteries. In terms of the catalytic activity and structural stability, pyrochlore oxides (A2[B2–xAx]O7–y) have emerged as promising candidates. However, a limited use of A-site cations (e.g., lead or bismuth cations) of reported pyrochlore catalysts have hampered broad understanding of their catalytic effect and structure. More seriously, the catalytic origin of the pyrochlore structure was not clearly revealed yet. Here, we report the new nanocrystalline yttrium ruthenate (Y2[Ru2–xYx]O7–y) with pyrochlore structure. The prepared pyrochlore oxide demonstrates comparable catalytic activities in both ORR and OER, compared to that of previously reported metal oxide-based catalysts such as perovskite oxides. Notably, we first find that the catalytic activity of the Y2[Ru2–xYx]O7–y is ...

The inositol polyphosphates are a group of multifunctional signaling metabolites whose synthesis is catalyzed by a family of inositol kinases that are evolutionarily conserved from yeast to humans. Inositol polyphosphate multikinase (IPMK) was first identified as a subunit of the arginine-responsive transcription complex in budding yeast. In addition to its role in the production of inositol tetrakis- and pentakisphosphates (IP4 and IP5), IPMK also exhibits phosphatidylinositol 3-kinase (PI3-kinase) activity. Through its PI3-kinase activity, IPMK activates Akt/PKB and its downstream signaling pathways. IPMK also regulates several protein targets non-catalytically via protein-protein interactions. These non-catalytic targets include cytosolic signaling factors and transcription factors in the nucleus. In this review, we highlight the many known functions of mammalian IPMK in controlling cellular signaling networks and discuss future challenges related to clarifying the unknown roles IPMK plays in physiology and disease.

Transporter layers for greater stability Although perovskite solar cells (PSCs) can have power conversion efficiencies exceeding 20%, they can have limited stability under ultraviolet irradiation. This is in part because the mesoporous TiO 2 used as an electron-transporting layer can photocatalyze unwanted reactions in the perovskite layer. Shin et al. report a low-temperature colloidal method for depositing La-doped BaSnO 3 films as a replacement for TiO 2 to reduce such ultraviolet-induced damage. Solar cells retained over 90% of their initial performance after 1000 hours of full sun illumination. Science , this issue p. 167

The development of active water oxidation catalysts is critical to achieve high efficiency in overall water splitting. Recently, sub-10 nm-sized monodispersed partially oxidized manganese oxide nanoparticles were shown to exhibit not only superior catalytic performance for oxygen evolution, but also unique electrokinetics, as compared to their bulk counterparts. In the present work, the water-oxidizing mechanism of partially oxidized MnO nanoparticles was investigated using integrated in situ spectroscopic and electrokinetic analyses. We successfully demonstrated that, in contrast to previously reported manganese (Mn)-based catalysts, Mn(III) species are stably generated on the surface of MnO nanoparticles via a proton-coupled electron transfer pathway. Furthermore, we confirmed as to MnO nanoparticles that the one-electron oxidation step from Mn(II) to Mn(III) is no longer the rate-determining step for water oxidation and that Mn(IV)═O species are generated as reaction intermediates during catalysis.

Metal oxide based solar thermal water splitting is a promising approach for using solar energy to produce H2 and O2. The normal protocol employed for this process involves thermal reduction of a metal oxide (MOx) at around 1500 °C to produce the reduced form of the metal oxide (MOx−δ) and O2. This step is followed by steam treatment of MOx−δ at around 1000 °C to yield MOx and H2. Owing to the need to use high temperatures, the traditional approach has several important drawbacks. In a study designed to improve this process, we found that Cu-loaded TiO2 (Cu/TiO2) effectively expels O2 upon irradiation with AM 1.5 1 Sun solar simulated light and that treatment of the reduced form of the reduction product Cu/TiO2−δ with steam at 140 °C generates H2. This new approach, termed as solar photochemical–thermal water splitting, has the potential to become an important method for converting solar energy into chemical energy.

Oxygen reduction reaction (ORR) or oxygen evolution reaction (OER) electrocatalysts including carbon-, non-precious metal-, metal alloy-, metal oxide-, and carbide/nitride-based materials are of great importance for energy conversion and storage technologies. Among them, metal oxides (e.g., perovskite and pyrochlore) are known to be promising candidates as electrocatalysts. Nevertheless, the intrinsic catalytic activities of pyrochlore oxides are still poorly understood because of the formation of undesirable phases derived from the synthesis processes. Herein, we present highly pure single crystalline pyrochlore nanoparticles with metallic conduction (Pb2Ru2O6.5) as an efficient bi-functional oxygen electrocatalyst. Notably, it has been experimentally shown that the covalency of Ru–O bonds affects the ORR and OER activities by comparing the X-ray absorption near edge structure (XANES) spectra of the metallic Pb2Ru2O6.5 and insulating Sm2Ru2O7 for the first time. Moreover, we followed the interatomic distance changes of Ru–O bonds using in situ X-ray absorption spectroscopy (XAS) to investigate the structural stabilities of the pyrochlore catalysts during electrocatalysis. The highly efficient metallic Pb2Ru2O6.5 exhibited outstanding bi-functional catalytic activities and stabilities for both ORR and OER in aqueous Zn–air batteries.

Metal fluorides (MFx) are one of the most attractive cathode candidates for Li ion batteries (LIBs) due to their high conversion potentials with large capacities. However, only a limited number of synthetic methods, generally involving highly toxic or inaccessible reagents, currently exist, which has made it difficult to produce well-designed nanostructures suitable for cathodes; consequently, harnessing their potential cathodic properties has been a challenge. Herein, we report a new bottom-up synthetic method utilizing ammonium fluoride (NH4F) for the preparation of anhydrous MFx (CuF2, FeF3, and CoF2)/mesoporous carbon (MSU–F–C) nanocomposites, whereby a series of metal precursor nanoparticles preconfined in mesoporous carbon were readily converted to anhydrous MFx through simple heat treatment with NH4F under solventless conditions. We demonstrate the versatility, lower toxicity, and efficiency of this synthetic method and, using XRD analysis, propose a mechanism for the reaction. All MFx/MSU–F–C prep...

In this study, the self-piercing rivet (SPR) joining of vibration-damping steel and aluminum alloy (Al5052-H32) is successfully carried out, for the first time to our knowledge, and the effects of die type and joint configuration on the mechanical performance, failure mode, and geometrical characteristics of the new joint are investigated. The vibration-damping steel and Al5052-H32 SPR joint exhibits the largest tensile&ndash, shear load when a flat die is used. An increase in the die taper angle and diameter decreases the mechanical performance of the joint due to the increase in volume of the die, leading to a smaller interlock width of the joint. The joint configuration with Al5052-H32 as a top sheet has superior mechanical performance compared with the reverse configuration, owing to the increase of the interlock width. All SPR joints of vibration-damping steel and Al5052-H32 show consistent rivet pull-out failure, regardless of the joint configuration, because of relatively small interlock width. It is also found that these SPR joints show better mechanical performance than those of SPFC590DP (a skin material of the vibration-damping steel) and Al5052-H32 under the Al5052-H32&ndash, top configuration.

Heteropoly acids (HPAs) are unique materials with interesting properties, including high acidity and proton conductivity. However, their low specific surface area and high solubility in polar solvents make them unattractive for catalytic or energy applications. This obstacle can be overcome by creating nanoporosity within the HPA. We synthesized mesoporous phosphotungstic acid (mPTA) with a spherical morphology through the self‐assembly of phosphotungstic acid (PTA) with a polymeric surfactant as stabilized by KCl and hydrothermal treatment. The mPTA nanostructures had a surface area of 93 m2 g−1 and a pore size of 4 nm. Their high thermal stability (ca. 450 °C) and lack of solubility in ethylene carbonate/diethyl carbonate (EC/DEC) electrolyte are beneficial for lithium‐ion batteries (LIBs). Optimized mPTA showed a reversible capacity of 872 mAh g−1 at 0.1 A g−1 even after 100 cycles for LIBs, as attributed to a super‐reduced state of HPA and the storage of Li ions within the mesochannels of mPTA. Refereed/Peer-reviewed