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Sand‐casting molds suffer from surface defects and low strength. An organic–inorganic binder conversion process, wherein an organic binder is converted to an inorganic binder, has been proposed to increase the application temperature of the sand‐casting mold and simplify the manufacturing process for precision casting. However, the usable temperature of the typical SiO2–Na2O binder system is limited to approximately 1000°C owing to the low liquefaction temperature of the compound. The resulting glass phase (Na2SiO3) exhibits low viscosity, and the casting of large objects results in low strength. Therefore, in this study, we propose a SiO2–Na2O–ZrO2 ternary inorganic binder system; the addition of zirconia (ZrO2) into sodium silicate (Na2SiO3) as an inorganic binder was expected to increase the operating temperature of the mold and improve its mechanical properties. The results confirmed that the addition of ZrO2 improved the mechanical properties by preventing the formation of Na2SiO3. In addition, a higher sintering temperature corresponded to smaller and larger amounts of Na2SiO3 and Na2ZrSiO5, respectively, and thus a higher strength. Therefore, we expect our developed ternary inorganic binder system to be highly advantageous for producing molds for high‐temperature and precision casting. [ABSTRACT FROM AUTHOR]

The design of high‐entropy single‐atom catalysts (HESAC) with 5.2 times higher entropy compared to single‐atom catalysts (SAC) is proposed, by using four different metals (FeCoNiRu‐HESAC) for oxygen reduction reaction (ORR). Fe active sites with intermetallic distances of 6.1 Å exhibit a low ORR overpotential of 0.44 V, which originates from weakening the adsorption of OH intermediates. Based on density functional theory (DFT) findings, the FeCoNiRu‐HESAC with a nitrogen‐doped sample were synthesized. The atomic structures are confirmed with X‐ray photoelectron spectroscopy (XPS), X‐ray absorption (XAS), and scanning transmission electron microscopy (STEM). The predicted high catalytic activity is experimentally verified, finding that FeCoNiRu‐HESAC has overpotentials of 0.41 and 0.37 V with Tafel slopes of 101 and 210 mVdec−1 at the current density of 1 mA cm−2 and the kinetic current densities of 8.2 and 5.3 mA cm−2, respectively, in acidic and alkaline electrolytes. These results are comparable with Pt/C. The FeCoNiRu‐HESAC is used for Zinc–air battery applications with an open circuit potential of 1.39 V and power density of 0.16 W cm−2. Therefore, a strategy guided by DFT is provided for the rational design of HESAC which can be replaced with high‐cost Pt catalysts toward ORR and beyond. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2‐to‐formate conversion is considered an economically viable process. In general, Zn‐based nanomaterials are well‐known to be highly efficient electrocatalysts for the conversion of CO2 to CO, but seldom do they exhibit excellent selectivity toward formate. In this article, we demonstrate that a heterointerface catalyst ZnO/ZnSnO3 with nanosheet morphology shows enhanced selectivity with a maximum Faradaic efficiency (FE) of 86% at −0.9 V versus reversible hydrogen electrode and larger current density for the conversion of CO2 to formate than pristine ZnO and ZnSnO3. In particular, the FEs of the C1 products (CO + HCOO−) exceed 98% over the potential window. The experimental measurements combined with theoretical calculations revealed that the ZnO in ZnO/ZnSnO3 heterojunction delivers the valence electron depletion and accordingly optimizes Zn d‐band center, which results in moderate Zn–O hybridization of HCOO* and weakened Zn–C hybridization of competing COOH*, thus greatly boosting the HCOOH generation. Our study highlights the importance of charge redistribution in catalysts on the selectivity of electrochemical CO2 reduction. [ABSTRACT FROM AUTHOR]

Even though grain boundaries (GBs) have been previously employed to increase the number of active catalytic sites or tune the binding energies of reaction intermediates for promoting electrocatalytic reactions, the effect of GBs on the tailoring of the local chemical environment on the catalyst surface has not been clarified thus far. In this study, a GBs‐enriched iridium (GB−Ir) was synthesized and examined for the alkaline hydrogen evolution reaction (HER). Operando Raman spectroscopy and density functional theory (DFT) calculations revealed that a local acid‐like environment with H3O+ intermediates was created in the GBs region owing to the electron‐enriched surface Ir atoms at the GBs. The H3O+ intermediates lowered the energy barrier for water dissociation and provided enough hydrogen proton to promote the generation of hydrogen spillover from the sites at the GBs to the sites away from the GBs, thus synergistically enhancing the hydrogen evolution activity. Notably, the GB−Ir catalyst exhibited a high alkaline HER activity (10 mV @ 10 mA cm−2, 20 mV dec−1). We believe that our findings will promote further research on GBs and the surface science of electrochemical reactions. [ABSTRACT FROM AUTHOR]

Simultaneous optimization of the energy level of water dissociation, hydrogen and hydroxide desorption is the key to achieving fast kinetics for the alkaline hydrogen evolution reaction (HER). Herein, the well‐dispersed Ru clusters on the surface of amorphous/crystalline CeO2‐δ (Ru/ac‐CeO2‐δ) is demonstrated to be an excellent electrocatalyst for significantly boosting the alkaline HER kinetics owing to the presence of unique oxygen vacancy (VO) and Ru Lewis acid–base pairs (LABPs). The representative Ru/ac‐CeO2‐δ exhibits an outstanding mass activity of 7180 mA mgRu−1 that is approximately 9 times higher than that of commercial Pt/C at the potential of −0.1 V (V vs RHE) and an extremely low overpotential of 21.2 mV at a geometric current density of 10 mA cm−2. Experimental and theoretical studies reveal that the VO as Lewis acid sites facilitate the adsorption of H2O and cleavage of H‐OH bonds, meanwhile, the weak Lewis basic Ru clusters favor for the hydrogen desorption. Importantly, the desorption of OH from VO sites is accelerated via a water‐assisted proton exchange pathway, and thus boost the kinetics of alkaline HER. This study sheds new light on the design of high‐efficiency electrocatalysts with LABPs for the enhanced alkaline HER. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) suffers from sluggish kinetics even on the benchmark RuO2 catalyst, due to the complex four sequential proton‐coupled electron transfer steps. Severe electrochemical oxidation and dissolution issues also make RuO2 fail as an alternative to highly expensive iridium‐based OER catalysts applied in proton exchange membrane water electrolysis. Herein, an acid‐stable W18O49‐δ matrix‐confined Ru solid solution oxide is developed with considerably reduced Ru loadings beyond commercial RuO2, to enhance the acidic OER kinetics and extend the long‐term durability simultaneously by incorporating Brønsted acid sites. The representative Ru0.6W17.4O49‐δ with 3D urchin‐like morphology achieves an excellent catalytic stability with ultra‐slow degradation rate and a high mass activity of 27 110 A g−1Ru @ 1.53 V versus RHE in 0.1 m HClO4 electrolyte, which is ≈10.8 times higher than that of commercial RuO2. The enhanced electron transfer from W to Ru during the OER process prevents the over‐oxidation of surface Ru sites extending the long‐term stability, while the incorporated Ru‐Obri‐W Brønsted acid sites accelerate the deprotonation step by promoting the mobility of proton from the oxo‐intermediate to the neighboring Obri sites, thus boosting the acidic OER kinetics. [ABSTRACT FROM AUTHOR]

In some countries with high population densities including Korea, chemical plants are densely distributed, and strict regulations are imposed. According to the Chemical Control Act, one gas detector must be installed every 10 m indoors and 20 m outdoors around a facility. However, the diffusion of chemicals should be evaluated based on area rather than perimeter. In the US and EU, gas detector locations are selected through chemical accident modeling. Here, we evaluated the feasibility of gas detector installation standards in the Chemicals Control Act by comparing highly volatile and toxic chemicals with sulfuric acid (relatively low volatility). Consequently, we suggested an appropriate installation location and number of gas detectors for initial countermeasures. For nitric acid, hydrochloric acid, and hydrofluoric acid, there was a difference in the number of detectors recommended via modeling and the number of detectors legally required. For the mezzanine design, four gas detectors should be installed on each floor in a 5‐story building; however, the modeling results showed that installing one was sufficient. For sulfuric acid with low vapor pressure, it is equitable to install a leak detector rather than a gas detector. Overall, regulations should be continuously evaluated for the response and prevention of chemical accidents. [ABSTRACT FROM AUTHOR]

The development of efficiently active and stable bifunctional noble‐metal‐based electrocatalysts toward overall water splitting is urgent and challenging. In this work, a rutile‐structured ruthenium‐zinc solid solution oxide with oxygen vacancies (Ru0.85Zn0.15O2‐δ) is developed by a simple molten salt method. With naturally abundant edges of ultrasmall nanoparticles clusters, Ru0.85Zn0.15O2‐δ requires ultralow overpotentials, 190 mV for acidic oxygen evolution reaction (OER) and 14 mV for alkaline hydrogen evolution reaction (HER), to reach 10 mA cm−2. Moreover, it shows superior activity and durability for overall water splitting in different electrolytes. Experimental characterizations and density functional theory calculations indicate that the incorporation of Zn and oxygen vacancies can optimize the electronic structure of RuO2 by charge redistribution, which dramatically suppresses the generation of soluble Rux>4 and allows optimized adsorption energies of oxygen intermediates for OER. Meanwhile, the incorporation of Zn can distort local structure to activate the dangling O atoms on the distorted Ru0.85Zn0.15O2‐δ as proton acceptors, which firmly bonds the H atom in H2O* to stabilize the H2O and considerably improves the HER activity. [ABSTRACT FROM AUTHOR]

Metal single‐atom (SA) catalysts have attracted immense attention due to the high catalytic efficiency given by the desired coordination environment of each metal atom. Yet, engineering the local electronic structure of SAs and multi‐atoms (MAs) still remains a challenge. Herein, an atomically dispersed catalyst comprised of Pt SAs, Pt‐Pt/V dual‐atoms, and small clusters supported on a vanadium and nitrogen co‐doped carbon (VNC) (denoted as Pt@VNC) surface is synthesized. In the Pt@VNC, both V and Pt atoms are evenly distributed on the surface of N‐doped carbon, while a few Pt atoms are linked to other Pt atoms via V, forming Pt clusters. The coordination structures of Pt atoms are modulated upon introducing atomically dispersed V sites (which generate small‐sized Pt clusters) and V2O5 clusters, showing extraordinary activity for the hydrogen evolution reaction (HER). Benefiting from the low charge transfer resistance, i.e., fast reaction kinetics, due to the synergistic effect of SAs and clusters, the Pt@VNC demonstrates superior catalytic efficiency and robust durability for the HER. It requires an overpotential of only 5 mV at a current density of 10 mA cm−2 and shows 15 times larger mass activity than the commercial 20 wt.% Pt/C catalyst. This novel catalyst‐design strategy paves a new way for maximizing catalytic efficiency by optimizing the coordination structure of metal atoms. [ABSTRACT FROM AUTHOR]

Reducing the particle sizes of transition metals [TMs] and avoiding their aggregation are crucial for increasing the TMs atom utilization and enhancing their industrial potential. However, it is still challenging to achieve uniform distributed and density-controlled TMs nanoclusters [NCs] under high temperatures due to the strong interatomic metallic bonds and high surface energy ofNCs. Herein, a series ofTMs NCs with controllable density and nitrogen-modulated surface are prepared with the assistance of a selected covalent organic polymer [COP], which can provide continuous anchoring sites and size-limited skeletons. The prepared Ir NCs show superior hydrogen evolution reaction [HER] and oxygen evolution reaction [OER] activities than commercial Pt/C and Ir/C in both acid and alkaline media. In particular, the as-prepared Ir NCs exhibit remarkable full water splitting performance, reaching a current density of 10 mA cm-2 at ultralow overpotentials of 1.42 and 1.43 V in alkaline and acidic electrolyte, respectively. The excellent electrocatalytic activities are attributed to the increased surface atom utilization and the improved intrinsic activity ofIr NCs. More importantly, the Ir NCs catalyst shows superior long-term stability due to the strong interaction between Ir NCs and the N-doped carbon layer. [ABSTRACT FROM AUTHOR]

The recent development of high‐energy LiCoO2 (LCO) and progress in the material recycling technology have brought Co‐based materials under the limelight, although their capacity still suffers from structural instability at highly delithiated states. Thus, in this study, a secondary doping ion substitution method is proposed to improve the electrochemical reversibility of LCO materials for Li‐ion batteries. To overcome the instability of LCO at highly delithiated states, Na ions are utilized as functional dopants to exert the pillar effect at the Li sites. In addition, Fe‐ion substitution (secondary dopant) is performed to provide thermodynamically stable surroundings for the Na‐ion doping. Density functional theory calculations reveal that the formation energy for the Na‐doped LCO is significantly reduced in the presence of Fe ions. Na and Fe doping improve the capacity retention as well as the average voltage decay at a cutoff voltage of 4.5 V. Furthermore, structural analysis indicates that the improved cycling stability results from the suppressed irreversible phase transition in the Na‐ and Fe‐doped LCO. This paper highlights the fabrication of high‐energy Co‐rich materials for high voltage operations, via a novel ion substitution method, indicating a new avenue for the manufacturing of layered cathode materials with a long cycle life. [ABSTRACT FROM AUTHOR]

While higher selectivity of nitrogen reduction reaction (NRR) to ammonia (NH3) is always achieved in alkali, the selectivity dependence on nitrogen (N2) protonation and mechanisms therein are unrevealed. Herein, we profile how the NRR selectivity theoretically relies upon the first protonation that is collectively regulated by proton (H) abundance and adsorption‐desorption, along with intermediate‐*NNH formation. By incorporating electronic metal modulators (M=Co, Ni, Cu, Zn) in nitrogenase‐imitated model‐iron polysulfide (FeSx), a series of FeMSx catalysts with tailorable protonation kinetics are obtained. The key intermediates behaviors traced by in situ FT‐IR and Raman spectroscopy and operando electrochemical impedance spectroscopy demonstrate the strong protonation kinetics‐dependent selectivity that mathematically follows a log‐linear Bradley curve. Strikingly, FeCuSx exhibits a record‐high selectivity of 75.05 % at −0.1 V (vs. RHE) for NH3 production in 0.1 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

In general, commercial ZnO owns the poor selectivity and activity toward electroreduction CO2 to formate. In contrast, the numbers of Sn‐based nanomaterials are reported as excellent electrocatalysts for formate production, however, the metallic Sn is more expensive than Zn. In this study, it is demonstrated that an atomically dispersed Sn on a tensile‐strained ZnO nanosheet (Sn SA/ZnO) shows dramatically improved activity and selectivity for formate production over a wide potential window compared with that of commercial ZnO. Especially, Sn SA/ZnO exhibits 205‐fold mass activity enhancement than the commercial Sn at −1.7 V versus reversible hydrogen electrode normalized with element Sn. The experimental measurements combined with theoretical calculations revealed that Sn SA/ZnO can effectively capture and activate CO2 by its exposed double‐active sites (Sn and O), while the tensile strain on its surface boosts the catalytic selectivity by strengthening the adsorption of the *HCOO intermediate for the electrochemical reduction of CO2 to formate. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P‐doped defective TiO2 substrate (Ru/P‐TiO2) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C‐like geometric activity and an excellent mass activity of 9984.3 mA mgRu−1 at −0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2, respectively. Experimental and theoretical studies indicated that using a rutile‐TiO2‐crystal‐phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile‐TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity. [ABSTRACT FROM AUTHOR]

NiFe‐based hydroxides are considered as promising nonprecious catalysts for water oxidation due to their low cost and easy preparation. However, the rational design of NiFe‐based electrocatalysts remains a great challenge to address the sluggish reaction kinetics and severe deactivation problems for oxygen evolution reaction (OER). Here, the authors report a facile approach to fabricate an amorphous Ce‐doped NiFe hydroxide catalyst, which enables high activity and outstanding stability toward OER in alkaline media. The overpotential of electrodeposited amorphous Ce‐doped NiFe is only 195 mV at 10 mA cm−2. Meanwhile, the durability of the amorphous Ce‐doped NiFe is maintained for 300 h at 100 mA cm−2. The comprehensive characterization results reveal that the improved electrochemical performance of the amorphous Ce‐doped NiFe catalyst is originated from the favorable oxidation transition of active sites enabled by Ce‐doping. It is a very good strategy to introduce highly oxidized state ions to regulate the NiFe‐based catalyst to improve the catalytic activity and stability. [ABSTRACT FROM AUTHOR]

Membrane fouling is a major problem that hinders the application of the membrane in water filtration. To address this issue, a novel reversed thermally induced phase separation (RTIPS) process is applied to fabricate a patterned polyethersulfone (PES) hollow fiber (HF) membrane using a structured spinneret. Surface patterning could induce turbulence, thereby preventing the accumulation of foulants on membrane surface. The RTIPS method requires lesser material with similar mechanical strength compared to that of conventional TIPS method. The fabrication process is optimized by changing the spinning conditions. A dope composition of 24 wt% PES is chosen to prepare the membrane. The chemical composition of the membrane is confirmed via sophisticated techniques such as Fourier‐transform infrared (FTIR) spectroscopy and X‐ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) images of the sample indicates the successful formation of the pattern on the shell side of the HFs. The prepared patterned HF membranes exhibits a high rejection of 97% of bovine serum albumin (BSA), which is comparable to or higher than that of commercial membranes. Moreover, the patterned membrane demonstrates better performance, thereby confirming the effectiveness of this modification in enhancing the antifouling nature. [ABSTRACT FROM AUTHOR]

Rational design of efficient hydrogen evolution reaction (HER) electrocatalysts for mass production of hydrogen via electrochemical water splitting is a challenging but pressing task. Herein, an in situ dual doping engineering from phosphomolybdic acid encapsulated within the bimetallic metal‐organic‐frameworks strategy to synthesize P,Mo dual doped Ru ultrasmall nanoparticles embedded in P‐doped porous carbon (P,Mo‐Ru@PC) for efficient HER is proposed. As a result, P,Mo‐Ru@PC achieves a low overpotential of 21 at 10 mA cm−2, low Tafel slopes of 21.7 mV dec−1, and a mass activity about 22 times greater than that of commercial 20 wt% Pt/C in alkaline media. First principle calculations demonstrate that introducing Mo and P atoms into Ru lattices triggers the in situ electron donation from Ru to Mo and P and consequently reduces the energy barrier for the HER. [ABSTRACT FROM AUTHOR]

Hydrogen generation by electrolysis of water in an alkaline solution is a promising technology for clean hydrogen energy. Amorphous materials show much better performance than their crystalline counterparts. However, it is still challenging to design amorphous metal materials. Here, a series of amorphous transition metal nanoparticles (NPs) is successfully synthesized using a twisted covalent organic network (CON) that can provide twisted carbon layers as well as asymmetrically distributed nitrogen. With the fixed monomer pore, a low loading amount of RuCl3 results in amorphous‐only Ru nanoclusters (NCs, 1.5 nm), while a high content of RuCl3 leads to crystalline dominant Ru NPs (3 nm). The mixed phased Ru‐CON catalyst for the hydrogen evolution reaction (HER) shows extremely low overpotential at 10 mA cm–2 (12.8 mV in 1.0 m KOH) and superior stability (after 100 h test, current loss 5.3% at 75 mA cm–2). More importantly, amorphous‐only Ru‐CON with smaller Ru NCs shows much better mass activity and considerable stability compared to mixed‐phase Ru‐CON materials since amorphous Ru NPs can provide more active sites than in their crystalline state. With this strategy, amorphous Fe NPs and Ir NPs are successfully prepared for extended applications, and the HER activities are reported. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 RuO2 with rich oxygen vacancies (a/c‐RuO2) was developed as a pH‐universal OER electrocatalyst. The a/c‐RuO2 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‐RuO2 also exhibits superior OER activities to commercial RuO2 and most reported OER catalysts under all pH conditions. Theoretical calculations indicated that the introduction of Na dopant and oxygen vacancy in RuO2 weakens the adsorption strength of the OER intermediates by engineering the d‐band center, thereby lowering the energy barrier for OER. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The exact understanding for each promotional role of cation and anion vacancies in bifunctional water splitting activity will assist in the development of an efficient activation strategy of inert catalysts. Herein, systematic first‐principles computations demonstrate that the synergy of anion–oxygen and cation–manganese vacancies (VO and VMn) in manganese dioxide (MnO2) nanosheets results in abnormal local lattice distortion and electronic modulation. Such alterations enrich the accessible active centers, increase conductivity, enhance the water dissociation step, and favor intermediate adsorption–desorption, consequently promoting HER and OER kinetics. As proof of concept, robust electrocatalysts, MnO2 ultrathin nanosheets doped with dual vacancies (DV–MnO2) are obtained via a maturely chemical strategy. Detailed characterizations confirm the cation vacancies‐VMn contribute to enhanced conductivity and anion vacancies‐VO enrich the active centers with optimized local electronic configurations, consistent with the simulative predictions. As expected, DV–MnO2 exhibits exceptional bifunctionality with the strong assistance of synergetic dual vacancies which act as abundant "hot spots" for active multiple intermediates. Leading to a lower cell voltage (1.55 V) in alkali electrolyte is required to reach 10 mA cm−2 for the overall water splitting system. These atomic‐level insights on synergetic DV can favor the development of activating strategy from inert electrocatalysts. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

To develop effective electrocatalytic splitting of acidic water, which is a key reaction for renewable energy conversion, the fundamental understanding of sluggish/destructive mechanism of the oxygen evolution reaction (OER) is essential. Through investigating atom/proton/electron transfers in the OER, the distinctive acid–base (AB) and direct‐coupling (DC) lattice oxygen mechanisms (LOMs) and adsorbates evolution mechanism (AEM) are elucidated, depending on the surface‐defect engineering condition. The designed catalysts are composed of a compressed metallic Ru‐core and oxidized Ru‐shell with Ni single atoms (SAs). The catalyst synthesized with hot acid treatment selectively follows AB‐LOM, exhibiting simultaneously enhanced activity and stability. It produces a current density of 10/100 mA cm−2 at a low overpotential of 184/229 mV and sustains water oxidation at a high current density of up to 20 mA cm−2 over ≈200 h in strongly acidic media. [ABSTRACT FROM AUTHOR]

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 Ru2P/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 Ru2P/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 Ru2P/WO3@NPC is achieved by electron transfer from NPC to Ru2P/WO3 and from Ru2P to WO3, which directly promotes the dissociation of water on W sites in WO3 and desorption of hydrogen on Ru sites in Ru2P. [ABSTRACT FROM AUTHOR]

Developing highly active, durable, and cost‐effective electrocatalysts for the oxygen evolution reaction (OER) is of prime importance in proton exchange membrane (PEM) water electrolysis techniques. Herein, a surface lanthanum‐deficient (SLD) iridium oxide as a highly efficient OER electrocatalyst is reported (labeled as La3IrO7‐SLD), which is obtained by electrochemical activation, and shows better activity and durability than that of commerically available IrO2 as well as most of the reported Ir‐based OER electrocatalysts. At a current density of 10 mA cm−2, the overpotential of La3IrO7‐SLD is 296 mV, which is lower than that of IrO2 (316 mV). Impressively, the increase of potential is less than 50 mV at a voltage–time chronopotentiometry extending for 60 000 s using a glass carbon electrode that is vastly superior to IrO2. Moreover, the mass activity of the catalyst is approximately five times higher than that of IrO2 at 1.60 V versus reversible hydrogen electrode. Density functional theory calculations suggest that a lattice oxygen participating mechanism with central Ir atoms serving as active sites (LOM‐Ir) rationalizes the high activity and durability for the La3IrO7‐SLD electrocatalyst. The favorable energy level of surface active Ir 5d orbitals relative to coordinated O 2p orbitals makes the La3IrO7‐SLD more active. [ABSTRACT FROM AUTHOR]

This paper presents a controller IC with on‐display capacitive sensor for touch and multi fingerprint function. Single sensor and the IC enable both touch and fingerprint without additional area or sensor. Fully balanced multi‐channel driving technique with proposed method removes column offset to maximize the immunity to display and external noise. Prototype IC is fabricated in a 65nm CMOS technology. This work achieves 31.6dB SNR with 0.7mmϕ stylus and 120Hz frame rate with 14x10 pixels TSP in touch mode, and 32dB SNR with 0.2mm cover glass and 200ms scan time in multi‐fingerprint mode with 5cmx3.5cm area. [ABSTRACT FROM AUTHOR]

Designing a facile strategy to access active and atomically dispersed metallic catalysts are highly challenging for single atom catalysts (SACs). Herein, a simple and fast approach is demonstrated to construct Pt catalysts with single atoms in large quantity via ball milling Pt precursor and N‐doped carbon support (K2PtCl4@NC‐M; M denotes ball‐milling). The as‐prepared K2PtCl4@NC‐M only requires a low overpotential of 11 mV and exhibits 17‐fold enhanced mass activity for the electrochemical hydrogen evolution compared to commercial 20 wt% Pt/C. The superior hydrogen evolution reaction (HER) catalytic activity of K2PtCl4@NC‐M can be attributed to the generation of Pt single atoms, which improves the utilization efficiency of Pt atoms and the introduction of Pt‐N2C2 active sites with near‐zero hydrogen adsorption energy. This viable ball milling method is found to be universally applicable to the fabrication of other single metal atoms, for example, rhodium and ruthenium (such as Mt‐N2C2, where Mt denotes single metal atom). This strategy also provides a promising and practical avenue toward large‐scale energy storage and conversion application. [ABSTRACT FROM AUTHOR]

Li‐excess 3d‐transition metal layered oxides are promising candidates in high‐energy‐density cathode materials for improving the mileage of electric vehicles. However, their low rate capability has hindered their practical application. The lack of understanding about the redox reactions and migration behavior at high C‐rates make it difficult to design Li‐excess materials with high rate capability. In this study, the characteristics of the atomic behavior that is predominant at fast charge/discharge are investigated by comparing cation‐ordered and cation‐disordered materials using X‐ray absorption spectroscopy (XAS). The difference in the atomic arrangement determines the dominance of the transition metal/oxygen redox reaction and the variations in transition metal–oxygen hybridization. In‐depth electrochemical analysis is combined with operando XAS analysis to reveal electronically and structurally preferred atomic behavior when a redox reaction occurs between oxygen and each transition metal under fast charge/discharge conditions. This provides a fundamental insight into the improvement of rate capability. Furthermore, this work provides guidance for identifying high‐energy‐density materials with complex structural properties. [ABSTRACT FROM AUTHOR]

Sub‐nanometric particles (SNPs) of atomic cluster sizes have shown great promise in many fields such as full atom‐to‐atom utilization, but their precise production and stabilization at high mass loadings remain a great challenge. As a solution to overcome this challenge, a strategy allowing synthesis and preservation of SNPs at high mass loadings within multishell hollow metal–organic frameworks (MOFs) is demonstrated. First, alternating water‐decomposable and water‐stable MOFs are stacked in succession to build multilayer MOFs. Next, using controlled hydrogen bonding affinity, isolated water molecules are selectively sieved through the hydrophobic nanocages of water‐stable MOFs and transferred one by one to water‐decomposable MOFs. The transmission of water molecules via controlled hydrogen bonding affinity through the water‐stable MOF layers is a key step to realize SNPs from various types of alternating water‐decomposable and water‐stable layers. This process transforms multilayer MOFs into SNP‐embedded multishell hollow MOFs. Additionally, the multishell stabilizes SNPs by π‐backbonding allowing high conductivity to be achieved via the hopping mechanism, and hollow interspaces minimize transport resistance. These features, as demonstrated using SNP‐embedded multishell hollow MOFs with up to five shells, lead to high electrochemical performances including high volumetric capacities and low overpotentials in Li–O2 batteries. [ABSTRACT FROM AUTHOR]

A nanocomposite of PC/Sb/SbPO4 (PC, phosphorus‐doped carbon) exhibits a high activity and an excellent selectivity for efficient electrocatalytic conversion of N2 to NH3 in both acidic and neutral electrolytes under ambient conditions. At a low reductive potential of −0.15 V versus the reversible hydrogen electrode (RHE), the PC/Sb/SbPO4 catalyst achieves a high Faradaic efficiency (FE) of 31 % for ammonia production in 0.1 m HCl under mild conditions. In particular, a remarkably high FE value of 34 % is achieved at a lower reductive potential of −0.1 V (vs. RHE) in a 0.1 m Na2SO4 solution, which is better than most reported electrocatalysts towards the nitrogen reduction reaction (NRR) in neutral electrolyte under mild conditions. The change in surface species and electrocatalytic performance before and after N2 reduction is explored by an ex situ method. PC and SbPO4 are both considered as the active species that enhanced the performance of NRR. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Developing highly efficient and durable bifunctional electrocatalyst for oxygen reduction (ORR) and oxygen evolution reaction (OER) is quite important for developing rechargeable zinc‐air batteries. Herein, one kind of manganese phosphate‐based electrocatalyst (Mnx(PO4)y/NPC) with high specific surface area (1106.9 m2 g−1) is prepared via a facile and scalable avenue, which possesses remarkable catalytic performance for the both ORR and OER, indicated by a more positive half‐wave potential of 0.87 V in 0.1 M KOH for the ORR as well as an overpotential of 0.37 V to achieve the current density of 10 mA cm−2 in 1 M KOH for the OER. Furthermore, the Mnx(PO4)y/NPC assembled rechargeable zinc‐air battery shows an excellent charge‐discharge cycling performance, revealed by the smaller sum of charge‐discharge potentials, comparable to that of Pt/C+IrO2. This research adds a new kind of electrocatalyst into the family of non‐noble metal‐based bifunctional electrocatalyst for rechargeable zinc‐air batteries. Re‐charge ahead: Mnx(PO4)y/NPC exhibits excellent catalytic performance for both ORR and OER, which possesses more superior electrochemical performance than Pt/C for the application in zinc‐air battery. The specific approaches to 668 mA h gZn−1. This work provides a facile and efficient avenue to synthesize non‐precious electrocatalyst with bifunctional catalytic effects and using in rechargeable zinc‐batteries. [ABSTRACT FROM AUTHOR]

The receptor‐interacting protein kinase 4 (RIP4), a serine/threonine kinase, is an important modulator of epidermal growth and cutaneous inflammation. We found that RIP4 expression was significantly increased in the lesional skin of psoriasis. However, the role and regulatory mechanism of RIP4 in psoriasis have not been characterized. After treatment with IL‐17, RIP4 mRNA and protein levels were increased in HaCaT cells. IL‐17 also activated the RIP4 promoter. To understand the functional role of RIP4 in keratinocyte and to investigate the genes regulated by RIP4, RNA‐based microarray analysis was performed. Among immune response‐related genes, CCL20 expression was significantly changed by RIP4. To identify RIP4‐interacting protein, an immunoprecipitation assay was performed. As a result, STAT3 was identified as a new protein that interacts with RIP4. The interaction of RIP4 and STAT3 enhanced STAT3 phosphorylation. In addition, the transcriptional activity of STAT3 induced by RIP4 regulated IL‐17‐mediated CCL20 expression in HaCaT cells. Taken together, these findings indicate that IL‐17 increased RIP4‐mediated STAT3 phosphorylation by directly interacting with STAT3. Thus, transcriptional activation of STAT3 promotes the expression of CCL20. Thus, activations of these signalling pathways by RIP4 may contribute to epithermal inflammation in psoriatic keratinocytes. [ABSTRACT FROM AUTHOR]

Abstract: 2D nonclose‐packed colloidal crystal patterns have received considerable attention in various fields, but it remains a challenge to fabricate patterns and manipulate their geometries regardless of substrate types and structures. Herein, a simple approach is developed for producing nonclose‐packed hydrogel colloidal crystalline patterns on flat and periodically micropatterned substrates by exposing close‐packed colloidal crystal monolayers to salt aqueous solutions. The patterns are achievable on flat surfaces like silicon, glass, graphene, poly(ethylene terephthalate), and poly(dimethyl siloxane) surfaces. Hydrogel colloidal spheres can deform into disk‐like or hemispherical particles on different material substrates. The colloid geometries and dimensions in the patterns are tunable by varying the salt type or concentration. The tunable colloidal crystalline patterns can form on periodically micropatterned substrates, resulting in novel hierarchical crystalline structures. The modification of the method is effective to easily fabricate nonclose‐packed hybrid colloidal crystal patterns where plasmonic nanoparticles are selectively assembled on the hydrogel particle surfaces. These patterned substrates modulate colors, reduce reflectivity of visible to near‐infrared light, and enhance transmittance. The nonclose‐packed colloidal patterns are useful as antireflection coating layers to enhance the solar thermoelectricity efficiencies of flat and micropatterned substrates. The optical tunability of colloidal crystal patterns enables developing colloid crystal‐based printable and erasable substrates. [ABSTRACT FROM AUTHOR]

Abstract: Reported herein is a catalytic platform for formation of unsymmetrical biaryls by the coupling between inert Csp2−CH3 and Csp2−H via a tandem catalytic strategy. The platform utilizes traditional AgNO3 catalyst and excess amount of K2S2O8 oxidant. The excessive oxidant present converts the traditional one‐electron Ag(I)/Ag(II) chemistry to two‐electron Ag(I)/Ag(III) one, enabling one‐pot synthesis of aryl‐aryl scaffolds by using unactivated cheap commodity chemicals. [ABSTRACT FROM AUTHOR]

The influence of Nd2O3 addition on the precipitation kinetics of lead chalcogenide (PbS) quantum dots ( QDs) in silicate glasses was investigated. Energy dispersive X-ray spectroscopy ( EDS) indicated that the Nd3+ ions are preferentially located inside the PbS QDs rather than in the glass matrix. Changes in diameter ( D) of PbS QDs exhibited smaller time dependencies (i.e., D≈ t0.270-0.286) than that predicted by the classical Lifshitz-Slyozov-Wagner ( LSW) theory. This is due to the limited concentrations of Pb2+ and S2− ions and the large diffusion distance inside the glass matrix. In addition, extended X-ray absorption fine structure ( EXAFS) results indicated that the formation of PbS QDs was retarded due to the presence of Nd2O3 in the glasses, as the large NdO x polyhedra interrupt the diffusion of Pb2+ and S2− ions. We believe that these Nd3+ ions are primarily located in PbS QDs in the form of Nd-O clusters, and that the PbS QDs are built on top of these clusters. [ABSTRACT FROM AUTHOR]

Despite a recent increase in the attention given to sodium rechargeable battery systems, they should be further advanced in terms of their energy density and reliability to successfully penetrate the rechargeable battery market. Here, a new room temperature ZEBRA-type Na-CuCl2 rechargeable battery is demonstrated that employs CuCl2 cathode material and nonflammable inorganic liquid electrolyte. The cathode delivers a high energy density of ≈580 Wh kg−1 with superior capacity retention over 1000 cycles as well as a high round-trip efficiency of ≈97%, which has never been obtained in an organic electrolyte system and high-temperature ZEBRA-type battery. These excellent electrochemical performances are mainly attributed to the use of the SO2-based inorganic electrolyte, which guarantees a reversible conversion reaction between CuCl2 and CuCl with NaCl. It is also demonstrated that the proposed battery chemistry can be extended to other copper halide materials including CuBr2 and CuF2, which also show highly promising battery performances as cathode materials for the Na-Cu halide battery system. [ABSTRACT FROM AUTHOR]