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H2O2photosynthesis has attracted great interest in harvesting and converting solar energy to chemical energy. Nevertheless, the high-efficiency process of H2O2photosynthesis is driven by the low H2O2productivity due to the recombination of photogenerated electron–hole pairs, especially in the absence of a sacrificial agent. In this work, we demonstrate that ultrathin ZnIn2S4nanosheets with S vacancies (Sv-ZIS) can serve as highly efficient catalysts for H2O2photosynthesis via O2/H2O redox. Mechanism studies confirm that Svin ZIS can extend the lifetimes of photogenerated carriers and suppress their recombination, which triggers the O2reduction and H2O oxidation to H2O2through radical initiation. Theoretical calculations suggest that the formation of Svcan strongly change the coordination structure of ZIS, modulating the adsorption abilities to intermediates and avoiding the overoxidation of H2O to O2during O2/H2O redox, synergistically promoting 2e–O2reduction and 2e–H2O oxidation for ultrahigh H2O2productivity. The optimal catalyst displays a H2O2productivity of 1706.4 μmol g–1h–1under visible-light irradiation without a sacrificial agent, which is ∼29 times higher than that of pristine ZIS (59.4 μmol g–1h–1) and even much higher than those of reported photocatalysts. Impressively, the apparent quantum efficiency is up to 9.9% at 420 nm, and the solar-to-chemical conversion efficiency reaches ∼0.81%, significantly higher than the value for natural synthetic plants (∼0.10%). This work provides a facile strategy to separate the photogenerated electron–hole pairs of ZIS for H2O2photosynthesis, which may promote fundamental research on solar energy harvest and conversion.

• Although the nano-dispersed precipitation of G-phase within the grain hardens the alloy remarkably, its large amount of precipitation at the grain boundary leads to serious alloy embrittlement. • For the first time, the crystal structure transition of nano-dispersed precipitates from the Fe 2 TiSi-L2 1 to the Ni 16 Ti 6 Si 7 -G phase is observed within the ferrite at the early stage of aging. • Guided by current TEM and DFT results, the interfacial energy is predicted to play a leading role in forming the cube-on-cube orientation relationship between α-Fe and G-phase. • Adopting the "cold-rolling and aging" process to effectively avoid its precipitation at grain boundaries, a class of high-performance ferroalloys with both high strength and good ductility is realized. A typical G-phase strengthened ferritic model alloy (1Ti:Fe-20Cr-3Ni-1Ti-3Si, wt.%) has been carefully studied using both advanced experimental (EBSD, TEM and APT) and theoretical (DFT) techniques. During the classic "solid solution and aging" process, the superfine (Fe, Ni) 2 TiSi-L2 1 particles densely precipitate within the ferritic grain and subsequently transform into the (Ni, Fe) 16 Ti 6 Si 7 -G phase. In the meanwhile, the elemental segregation at grain boundaries and the resulting precipitation of a large amount of the (Ni, Fe) 16 Ti 6 Si 7 -G phase are also observed. These nanoscale microstructural evolutions result in a remarkable increase in hardness (100–300 HV) and severe embrittlement. When the "cold rolling and aging" process is used, the brittle fracture is effectively suppressed without loss of nano-precipitation strengthening effect. Superhigh yield strength of 1700 MPa with 4% elongation at break is achieved. This key improvement in mechanical properties is mainly attributed to the pre-cold rolling process which effectively avoids the dense precipitation of the G-phase at the grain boundary. These findings could shed light on the further exploration of the precipitation site via optimal processing strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

The physicochemical properties and catalytic performance of transition metals are highly phase-dependent. Ru-based nanomaterials are superior catalysts toward hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR), but studies are mostly limited to conventional hexagonal-close-packed (hcp) Ru, mainly arising from the difficulty in synthesizing Ru with pure face-centered-cubic (fcc) phase. Herein, we report a crystal-phase-dependent catalytic study of MoOx-modified Ru (MoOx-Ru fcc and MoOx-Ru hcp) for bifunctional HER and HOR. MoOx-Ru fcc is proven to outperform MoOx-Ru hcp in catalyzing both HER and HOR with much higher catalytic activity and more durable stability. The modification effect of MoOxgives rise to optimal adsorption of H and OH especially on fcc Ru, which thus has resulted in the superior catalytic performance. This work highlights the significance of phase engineering in constructing superior electrocatalysts and may stimulate more efforts on phase engineering of other metal-based materials for diversified applications.

• A one-step synthesis strategy is developed for preparing core-shell bimetallic hexacyanoferrate. • DFT calculations confirm that ordered-disorder induce the formation of core-shell structure. • The MnFeHCF@MnFeHCF exhibits a larger BET area, higher Na+ content and lower Fe(CN) 6 vacancies. • The diffusion mechanism of Na+ ions in both core-shell electrodes is discussed in detail. • The stability mechanism of NiHCF shell on the properties of FeHCF core is unraveled. Recently, the design of core-shell hierarchical architecture plays an important role in improving the electrochemical performance of Prussian blue analogue cathodes (PBAs). Unfortunately, the inconvenient stepwise preparation and the strict lattice-matching requirement have restricted the development of core-shell PBAs. Herein, we demonstrate a one-step synthesis strategy to synthesize core-shell manganese hexacyanoferrate (MnFeHCF@MnFeHCF) for the first time. And the formation mechanism of the core-shell hierarchical architecture is investigated by first-principles calculations. It is found that the as-obtained MnFeHCF@MnFeHCF act out the superior intrinsic natures, which not only can obtain a larger specific surface area and lower Fe(CN) 6 vacancies but also can activate more Na-storage sites. Compared with the manganese hexacyanoferrate (MnHCF), the iron hexacyanoferrate (FeHCF), and even the traditional core-shell nickel hexacyanoferrate (FeHCF@NiHCF) prepared by a stepwise method, the MnFeHCF@MnFeHCF demonstrates a superior rate performance, which achieves a high capacity of 131 mAh g−1 at 50 mA g−1 and delivers a considerable discharge capacity of about 100 mAh g−1 even at 1600 mA g−1. Meantime, the capacity retention can reach up to nearly 80% after 500 cycles. The improved performances could be mainly originated from two aspects: on the one hand, Mn substitution is helpful to enhance the material conductivity; on the other hand, the core-shell structure with matched lattice parameters is more favorable to enhance the diffusion coefficient of sodium ions. Beside, the structural transformation of MnFeHCF@MnFeHCF upon the extraction/insertion of sodium ions is instrumental in releasing the interior stress and effectively maintaining the integrity of the crystal structure. [ABSTRACT FROM AUTHOR]

A carbon free self supported Mott-Schottky heterostructure was constructed as an efficient cathode catalyst for lithium oxygen batteries, achieving homogeneous contact between the two materials for strong interfacial interactions.The heterostructure triggered interfacial perturbations and band structure changes, which accelerated oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics, resulting in an extremely long cycle life of 800 cycles and an extremely low overpotential of 0.73 V.Combined with advanced characterization techniques and density functional theory calculations, the underlying mechanism behind the boosted ORR/OER activities and the electrocatalytic mechanism were revealed.

[Display omitted] • The typical lamellar structure made COF TDBA-TPA have a larger specific surface area. • COF TDBA-TPA had a large number of catalytically active sites (–C O, –NH 2 , –C N). • The adsorption kinetic equilibrium of COF TDBA-TPA was reached at 10 min. • COF TDBA-TPA can detect and remove HMIs in sewage and soil. Here, tripolycyanamide (TPA) and 2,4,6-triformyl pyrogallol (TDBA) are used to prepare a highly crystalline covalent-organic frameworks based on imine linkages (COF TDBA-TPA) for heavy metal ions (HMIs) detection and removal. Each unit of COF TDBA-TPA had 6 adsorption sites for HMIs (–C O, –NH 2 , –C N), which could selectively capture HMIs. The typical lamellar structure made COF TDBA-TPA have a larger specific surface area, and the mesoporous structure provided numerous channels for the adsorption of HMIs. Therefore, the COF TDBA-TPA -based electrochemical sensor could realize the detection of Cd2+, Cu2+, Pb2+, Hg2+ and Zn2+ in drinking water, simultaneously. The limits of detection for five HMIs were as low as 0.922 nM, 0.450 nM, 0.309 nM, 0.208 nM and 0.526 nM, respectively. The adsorption capacity of COF TDBA-TPA for each HMI was as high as 711.6 mg/g, 716.9 mg/g, 603.7 mg/g and 618.3 mg/g, respectively. Compared with other adsorbents, it had higher capacity and faster adsorption kinetics. After being recycled five times, the adsorption performance was maintained. This not only provides a reliable platform for the removal of HMIs in wastewater, but also provides new ideas for the use of COFs in the electrochemical field. [ABSTRACT FROM AUTHOR]

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[Display omitted] • Novel and durable Al-Si/Al 2 O 3 -AlN with tunable melting temperature were prepared. • The Al-Si alloy and Al 2 O 3 shell were prepared by the reaction of SiO 2 with melted Al. • The shell crack repaired itself by nitriding of melted Al to form Al 2 O 3 -AlN shell. • The Al 2 O 3 -AlN shell can obviously improve the thermal stability of composite PCM. • The Al-Si/Al 2 O 3 -AlN can be used in thermal storage systems for more than 6 years. The development of high temperature phase change materials (PCMs) with great comprehensive performance is significant in the future thermal energy storage system. In this study, novel and durable Al-Si/Al 2 O 3 -AlN composite PCMs with controllable melting temperature were successfully synthesized by using pristine Al powder as raw material and tetraethyl orthosilicate as SiO 2 source. The Al 2 O 3 shell and Al-Si alloy were in-situ produced via the substitution reaction between molten Al and SiO 2. Importantly, the crack caused by the incomplete encapsulation of the Al 2 O 3 shell could repair itself by the nitridation reaction of internal molten Al and thereby forming a highly dense Al 2 O 3 -AlN composite shell. The produced dense Al 2 O 3 -AlN composite shell could significantly improve the thermal cycling stability of composite PCMs, and thus, the thermal storage density decrease of the Al-Si/Al 2 O 3 -AlN (59.8 J/g to 77.7 J/g) was far less than that of the Al-Si/Al 2 O 3 (118.5 J/g) after 3000 thermal cycles. Moreover, the synthesized Al-Si/Al 2 O 3 -AlN still exhibited a controllable melting temperature (571.5–637.9 ℃), relatively high thermal storage density (105.6–150.7 J/g), great dimensional stability and structural stability after 3000 thermal cycles. Hence, the synthesized Al-Si/Al 2 O 3 -AlN composite PCMs, as promising preferential thermal energy storage materials, can be stably used in the energy utilization efficiency improvement of various systems for more than 6 years. [ABSTRACT FROM AUTHOR]

Harvesting distributed and low-quality mechanical energies by triboelectric nanogenerators to power electrochemical reactions is beneficial to electric energy saving and certain applications. However, the conventional self-powered electrochemical process is awkward about the reaction rate, energy conversion efficiency, high-operation frequency, and mismatched impedance. Here we demonstrate an advanced self-powered electrochemical system. In comparison with the conventional system that is inert in activity, the superior power management and electrochemical reaction regulation in tandem make the novel system outstanding for hydrogen peroxide production. In addition to the visible product, an internal current efficiency of 24.6% in the system was achieved. The developed system provides an optimization strategy toward electric energy saving for electrochemical reactions as well as enabling their applications in remote areas by converting environmental mechanical vibrational energy for ecological improvement or recyclable chemical fuel generation.

The phase equilibria in the Zr–Cu–Ni ternary system are investigated combined with X-ray diffraction, electron probe micro-analysis and differential scanning calorimetry. Two isothermal sections of the Zr–Cu–Ni ternary system at 1 000 °C and 1 100 °C are experimentally established. Most of the binary intermetallic compounds, e. g. Zr7Ni10, ZrNi, ZrNi5, Zr14Cu51, and Zr2Cu9, show a remarkable ternary solubility. A new ternary compound named τ3(Zr31.1–30.7· Cu28.5–40.3Ni40.4–29.0) is detected at 1 000 °C and dissolved at 1 020 °C because the nearby large liquid phase field further expands. The newly determined phase equilibria will provide important information for both thermodynamic assessment and alloy design of Zr-based metallic glass.

Objectives. The rapidly evolving organ failure and high short-run mortality of acute-on-chronic liver failure (ACLF) are inseparable from the role of systemic inflammatory response. S100A8 and S100A9 are associated with the excessive cytokine storm and play a decisive part within the process of inflammation. We aimed to clarify the role of them in predicting prognosis of hepatitis B virus-related ACLF (HBV-ACLF). Methods. S100A8 and S100A9 levels were analyzed in plasma of 187 transplant-free HBV-ACLF patients, 28 healthy controls and 40 chronic hepatitis B (CHB) patients. S100A8 and S100A9 mRNAs were checked in liver samples from 32 HBV-ACLF patients with liver transplantation, 19 patients undergoing surgery for hepatic hemangioma and 10 CHB patients with needle biopsy. Results. The plasma levels of the S100A8 and S100A9 were higher in HBV-ACLF patients than in CHB patients (S100A8 : P<0.001 and S100A9 : P<0.001) and healthy controls (S100A8 : P<0.001 and S100A9 : P<0.001), and similar results were obtained for mRNA expression. Moreover, both proteins were related to ACLF grade, different types of organ failure, and infection, and they correlated with other prognostic scoring systems. S100A8 and S100A9 can dependently predict 28/90-day mortality (28-day: S100A8: hazard ratio (HR): 1.027; 95% confidence interval (CI): 1.007–1.048; P=0.026, S100A9 : HR: 1.009; 95% CI: 1.001–1.017; P=0.007, 90-day: S100A8 : HR: 1.023; 95% CI: 1.011–1.035; P=0.004, S100A9 : HR: 1.008; 95% CI: 1.004–1.012; and P<0.001). Among all of the scoring systems, the combined scoring model (S100A8 and S100A9 jointly with the Chronic Liver Failure-Consortium Organ Failure score (CLIF-C OFs)) displayed the highest area under the receiver operating curve (0.923 (95% CI, 0.887–0.961)) in the prediction of 90-day mortality. Conclusions. S100A8 and S100A9 are promising biomarkers for the analysis of risk stratification and prognosis in ACLF patients. In addition, combining them with the CLIF-C OFs may better predict the prognosis of ACLF.

Constructing 3D skeletons modified with lithiophilic seeds has proven effective in achieving dendrite-free lithium metal anodes. However, these lithiophilic seeds are mostly alloy- or conversion-type materials, and they tend to aggregate and redistribute during cycling, resulting in the failure of regulating Li deposition. Herein, we address this crucial but long-neglected issue by using intercalation-type lithiophilic seeds, which enable antiaggregation owing to their negligible volume expansion and high electrochemical stability against Li. To exemplify this, a 3D carbon-based host is built, in which ultrafine TiO2seeds are uniformly embedded in nitrogen-doped hollow porous carbon spheres (N-HPCSs). The TiO2@N-HPCSs electrode exhibits superior Coulombic efficiency, high-rate capability, and long-term stability when evaluated as compertitive anodes for Li metal batteries. Furthermore, the superiority of intercalation-type seeds is comprehensively revealed through controlled experiments by various in situ/ex situ electron and optical microscopies, which highlights the excellent structural stability and lithiophilicity of TiO2nanoseeds upon repeated cycling.

Ocean wave energy is one of the most promising clean and renewable energy sources, so developing effective methods to collect such ‘random’ and ultra-low frequency energy is indispensable. The invention of triboelectric nanogenerators (TENGs) provides new prospects for large-scale blue energy harvesting. In this work, a new spherical TENG based on the coupling of spring-assisted structure and swing structure, integrated with a charge excitation circuit (CEC), was constructed to scavenge water wave energy. The particular structure can transform low-frequency water wave vibrations to high-frequency motions, elevating the frequencies of electrical outputs. Moreover, a TENG array consisting of four TENGs with CECs was fabricated, exhibiting a maximum output power of 16.6 mW and a 205 times enhanced output current of 23.3 mA. The charge excitation TENG array was demonstrated to successfully power a digital thermometer and a wireless signal transmission and reception system without any external power supply. Our study not only provides a new type of TENG with improved performance, but also offers a strategy for constructing maritime internet of things (IoTs) system.

By taking into account the ballistic mixing caused by recoil implantation and cascade collision, a model that describing effective free energy for alloys under irradiation from the perspective of diffusion equilibrium was used to study the effect of irradiation-induced defects on phase stability in U-Zr binary system. Based on the effective free energy model and the thermodynamic model, dynamical phase diagrams of U-Zr alloy under different irradiation intensities were calculated, and the differences between the dynamical phase diagram and thermodynamic equilibrium phase diagram (TEPD) were discussed. The obtained results indicate that, under irradiation, the high-temperature stable γ(U, Zr) phase can be stabilized resulting in two invariant reactions at low temperature, which could be ascribed to the domination of irradiation-induced ballistic mixing.