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Considering their superior charge-transfer characteristics, easy tenability of energy levels, and low production cost, organic semiconductors are ideal for photoelectrochemical (PEC) hydrogen production. However, organic-semiconductor-based photoelectrodes have not been extensively explored for PEC water-splitting because of their low stability in water. Herein, we report high-performance and stable organic-semiconductors photoanodes consisting of p-type polymers and n-type non-fullerene materials, which is passivated using nickel foils, GaIn eutectic, and layered double hydroxides as model materials. We achieve a photocurrent density of 15.1 mA cm−2 at 1.23 V vs. reversible hydrogen electrode (RHE) with an onset potential of 0.55 V vs. RHE and a record high half-cell solar-to-hydrogen conversion efficiency of 4.33% under AM 1.5 G solar simulated light. After conducting the stability test at 1.3 V vs. RHE for 10 h, 90% of the initial photocurrent density are retained, whereas the photoactive layer without passivation lost its activity within a few minutes., While organic semiconductors may be useful in photoelectrochemical water-splitting materials, they show low stability in water. Here, the authors report high-performance and stable organic-semiconductor-based photoanodes passivated using nickel foils, GaIn eutectic, and layered double hydroxides.

Spinel oxides are versatile and functional materials with physicochemical properties that are significantly influenced by their structural disorder. The transition from layered double hydroxides (LDHs) to mixed metal oxides (MMOs) containing spinel oxides is a powerful approach to create materials with tailored properties suitable for various applications. Herein, we report the control of structural ordering in spinels related to the crystallinity, cationic inversion, and coordination number of constituent atoms by varying the transformation energy. Transformation from LDHs to spinels with higher applied energy leads to higher crystallinity, lower degree of inversion, and lower ratios of low-coordinated atoms to fully coordinated atoms after treatment with acid. We provide a general framework for controlling structural ordering, that can be applied to other spinels and metal oxides. In addition, LDHs and MMOs possess many chemical and structural degrees of freedom, making it possible to create materials that suit the needs of different applications, such as memory, sensors, catalysis, and energy conversion.

Strongly correlated manganites have a wide range of fascinating magnetic and electronic properties, one example being the coexistence of ferromagnetic and insulating properties in lightly-doped bulk. However, it is difficult to translate bulk properties to films. Here, this problem is overcome by thin film nanoengineering of the test case system, La0.9Ba0.1MnO3 (LBMO). This was achieved by using vertically aligned nanocomposite (VAN) thin films of LBMO + CeO2 in which CeO2 nanocolumns form embedded in a LBMO matrix. The CeO2 columns produce uniform tensile straining of the LBMO. Also light Ce doping of intrinsic cation vacancies in the LBMO occurs. Together, these factors strongly reduced the double exchange coupling and metallicity. Hence, while standard plain reference films showed an insulator-to-metal transition at >200 K, originating from defects and complex structural relaxation, the VAN LBMO films exhibited ferromagnetic insulating properties (while maintaining a Tc of 188 K). This is the first time that a combined strain + doping method is used in a VAN system to realise exemplary properties which cannot be realised in plain films. This work represents an important step in engineering high performance spintronic and multiferroic thin film devices.

Characterizing the genetic diversity and population structure of breeding materials is essential for breeding to improve crop plants. The potato is an important non-cereal food crop worldwide, but breeding potatoes remains challenging owing to their auto-tetraploidy and highly heterozygous genome. We evaluated the genetic structure of a 110-line Korean potato germplasm using the SolCAP 8303 single nucleotide polymorphism (SNP) Infinium array and compared it with potato clones from other countries to understand the genetic landscape of cultivated potatoes. Following the tetraploid model, we conducted population structure analysis, revealing three subpopulations represented by two Korean potato groups and one separate foreign potato group within 110 lines. When analyzing 393 global potato clones, country/region-specific genetic patterns were revealed. The Korean potato clones exhibited higher heterozygosity than those from Japan, the United States, and other potato landraces. We also employed integrated extended haplotype homozygosity (iHS) and cross-population extended haplotype homozygosity (XP-EHH) to identify selection signatures spanning candidate genes associated with biotic and abiotic stress tolerance. Based on the informativeness of SNPs for dosage genotyping calls, 10 highly informative SNPs discriminating all 393 potatoes were identified. Our results could help understanding a potato breeding history that reflects regional adaptations and distinct market demands.

Material formation mechanisms and their selective realization must be well understood for the development of new materials for advanced technologies. Since nanomaterials demonstrate higher specific surface energies compared to their corresponding bulk materials, the homoepitaxial growth of nanomaterials on bulk materials is not thermodynamically favorable. We observed the homoepitaxial growth of nanowires with constant outer diameters on bulk materials in two different, solution-based growth systems. We also suggested potential mechanisms of the spontaneous and homoepitaxial growth of the ZnO nanostructures based on the characterization results. The first key factor for favorable growth was the crystal facet stabilization effect of capping agents during the early stages of growth. The second factor was the change in the dominant growth mode during the reaction in a closed system. The spontaneous, homoepitaxial growth of nanomaterials enables the realization of unprecedented, complex, hierarchical, single-crystalline structures required for future technologies.

Lead-free perovskite oxide thin films prepared by alloying of titanates and materials with lower melting points are shown to have enhanced ferroelectric and dielectric properties. BaTiO3 (or SrTiO3) with 25% addition of BiFeO3 has much improved crystalline perfection because of the lower melting point of the BiFeO3 giving enhanced growth kinetics. The maximum dielectric peak temperature of BaTiO3 is increased by ~ 200 °C and leakage currents are reduced by up to a factor of ~ 100. The loss tangent reduces up to 300 °C, with a factor of > 14 reduction at room temperature. The dielectric breakdown strength is higher by a factor of ~ 3 (> 2200 kV cm−1) and from room temperature up to 500 °C the dielectric constant is > 1000. Also, a low variation of dielectric constant of ~ 9% from room temperature to 330 °C is obtained, compared to ~ 110% for BaTiO3. The maximum polarization (Pmax) is double that of BaTiO3, at 125.3 μC cm−2. The film has high energy storage densities of > 52 J cm−3 at 2050 kV cm−1, matching Pb-based ferroelectric films. The strongly improved performance is important for applications in energy storage and in high temperature (up to 300 °C) capacitors as well as wider application in other electronic and energy technologies.

Summary Phase transformation from layered double hydroxides (LDHs) into mixed metal oxides (MMOs) has been widely used in various catalytic applications owing to its numerous advantages over conventional synthesis methods. Herein we report the results of selective phase transformation of LDHs into spinels and delafossites for the preparation of phase-pure MMO catalysts. Pure cuprous delafossites and cupric spinels were selectively obtained through heat treatment of Cu-based LDHs followed by post-treatments. This enabled the study of the crystalline-phase-dependent CO oxidation activity of the MMO catalysts and their physicochemical properties. The spinel catalysts exhibited higher CO oxidation activities, in comparison with those of the delafossites, with greater redox properties and improved active sites for CO adsorption. Although the crystalline phases were derived from the same LDH precursors, the catalytic properties of the end product were greatly influenced by their crystal structures.

Highly porous thin films and nanostructure arrays are created by a simple process of selective dissolution of a water‐soluble material, Sr3Al2O6. Heteroepitaxial nanocomposite films with self‐separated phases of a target material and Sr3Al2O6 are first prepared by physical vapor deposition. NiO, ZnO, and Ni1− xMgxO are used as the target materials. Only the Sr3Al2O6 phase in each nanocomposite film is selectively dissolved by dipping the film in water for 30 s at room temperature. This gentle and fast method minimizes damage to the remaining target materials and side reactions that can generate impurity phases. The morphologies and dimensions of the pores and nanostructures are controlled by the relative wettability of the separated phases on the growth substrates. The supercapacitor properties of the porous NiO films are enhanced compared to plain NiO films. The method can also be used to prepare porous films or nanostructure arrays of other oxides, metals, chalcogenides, and nitrides, as well as films or nanostructures with single‐crystalline, polycrystalline, or amorphous nature.

We report record energy storage density (>80 J cm−3) in Pb-free relaxor ferroelectrics based on Mn-doped BiFeO3–BaTiO3 thin films. Rapid interval deposition was used to impose layer-by-layer growth improving crystallinity and lowering unwanted defects concentration. The growth and Mn doping produced an order of magnitude lower leakage, with strongly reduced dielectric loss (from room temperature to >300 °C, and 100 Hz to 1 MHz), e.g. by a factor of 5 at 225 °C and 25 kHz. At room temperature (RT), the dielectric breakdown strength increased by a factor of 1.5 to >3000 kV cm−1 while the dielectric constant remained flat, at ~1000 from RT to 350 °C. The films perform better than competing materials (e.g. PZT and SrTiO3-based) while being Pb-free and while operating up to 350 °C, which SrTiO3-based systems do not. Our work gives considerable promise for high energy and power density capacitors for harsh environments.

Electric field control of magnetism is a critical future technology for low-power, ultrahigh density memory. However, despite intensive research efforts, no practical material systems have emerged. Interface-coupled, composite systems containing ferroelectric and ferri-/ferromagnetic elements have been widely explored, but they have a range of problems, for example, substrate clamping, large leakage, and inability to miniaturize. In this work, through careful material selection, design, and nanoengineering, a high-performance room-temperature magnetoelectric system is demonstrated. The clamping problem is overcome by using a vertically aligned nanocomposite structure in which the strain coupling is independent of the substrate. To overcome the leakage problem, three key novel advances are introduced: a low leakage ferroelectric, Na0.5Bi0.5TiO3; ferroelectric–ferrimagnetic vertical interfaces which are not conducting; and current blockage via a rectifying interface between the film and the Nb-doped SrTiO3 substrate. The new multiferroic nanocomposite (Na0.5Bi0.5TiO3–CoFe2O4) thin-film system enables, for the first time, large-scale in situ electric field control of magnetic anisotropy at room temperature in a system applicable for magnetoelectric random access memory, with a magnetoelectric coefficient of 1.25 × 10–9 s m–1.

The architecture, engineering, and construction (AEC) industry consume approximately 23% of the national energy annually, and are considered among the highest energy consuming industries. Recently, several studies have focused on establishing strategies to reduce the emissions of carbon dioxide in the AEC industry by utilisation of low-carbon materials, material reuse, recycling and minimal usage; selection of an optimal structural system and structural optimisation; and optimisation of construction operations. While several studies examined material selection and replacement in concrete, there is a paucity of studies investigating the replacement and implementation of high-strength re-bars to lower the carbon dioxide emissions in buildings. To fill this research gap, the purpose of this study involves calculating the emissions of carbon dioxide by applying high-strength reinforcement bars in three different types of buildings. The input–output analysis method was adopted to compute the emissions of carbon dioxide by using the yield strength and size. This study showed that the application of the high-strength re-bars is beneficial in reducing the input amount of materials, although the quantity of reinforcing bars on the development and splice increased. Furthermore, the application of high-strength deformed bars is also advantageous as a means of carbon dioxide reduction in the studied structural systems. In this study, the CO2 emissions of three different structural systems indicated that implementing SD500 re-bars is the most effective method to reduce carbon dioxide emissions.

Near-infrared (NIR)-emitting PbS-based quantum dots (QDs) and exfoliated layered double hydroxide (LDH) nanosheets were self-assembled to form photostable composites for NIR-emitting codes. PbS QDs prepared by a pyrolysis synthetic method or PbS–CdS (core–shell) QDs prepared by a cation exchange using PbS QDs were transferred to aqueous solutions by surface ligand exchange to dihydrolipoic acid (DHLA). The DHLA-decorated QDs and exfoliated LDH nanosheets were assembled by electrostatic interactions during vortexing. The QD–LDH composite films prepared by drop-casting exhibit more than 500% higher NIR PL intensities than the counterpart QD films (without LDH matrices) under identical conditions (i.e., QD concentration). Photostability tests under continuous light irradiation reveal that the PbS–CdS QD films are more photostable than the PbS QD films. Formation of the QD–LDH composites gives rise to further enhancement in the photostability of the film. The photostable PbS–CdS QD–LDH composite films were used to create novel NIR-emitting codes. NIR fluorescence images of a pattern of two kinds of PbS–CdS QD–LDH composite films were recorded with an InGaAs CCD camera equipped with optical filters.

Exosomes are enclosed compartments that are released from cells and that can transport biological contents for the purpose of intercellular communications. Research into exosomes is hindered by their rarity. In this article, we introduce a device that uses centrifugal force and a filter with micro-sized pores to generate a large quantity of cell-derived nanovesicles. The device has a simple polycarbonate structure to hold the filter, and operates in a common centrifuge. Nanovesicles are similar in size and membrane structure to exosomes. Nanovesicles contain intracellular RNAs ranging from microRNA to mRNA, intracellular proteins, and plasma membrane proteins. The quantity of nanovesicles produced using the device is 250 times the quantity of naturally secreted exosomes. Also, the quantity of intracellular contents in nanovesicles is twice that in exosomes. Nanovesicles generated from murine embryonic stem cells can transfer RNAs to target cells. Therefore, this novel device and the nanovesicles that it generates are expected to be used in exosome-related research, and can be applied in various applications such as drug delivery and cell-based therapy.

The reason for the upper limit on the height of spinnable carbon nanotube (CNT) forests was studied. To analyze the differences between CNT forests with different heights, we synthesized CNT forests using different growth times (3, 6, 9, 12, 15, and 60 min). The height of the CNT forests increased from 260 μm at 3 min to 1.7 mm at 60 min, and the spinnability decreased sharply after 9 min of growth, where a wavy morphology first appeared. Raman analysis of the CNT forest grown for 9 min showed that the intensity ratio of G-band to D-band at the upper region was 1.50 and that near the bottom was 1.14. We also found that the reaction termination process affected the spinnability of the CNT forests. Depending on the termination process, both spinnable and non-spinnable CNT forests could be selectively synthesized, because of the different morphologies in their lower regions. The results suggested that any wavy morphology produced due to a disturbance in growth conditions causes a loss of spinnability.

Resistive switches are non-volatile memory cells based on nano-ionic redox processes that offer energy efficient device architectures and open pathways to neuromorphics and cognitive computing. However, channel formation typically requires an irreversible, not well controlled electroforming process, giving difficulty to independently control ionic and electronic properties. The device performance is also limited by the incomplete understanding of the underlying mechanisms. Here, we report a novel memristive model material system based on self-assembled Sm-doped CeO2 and SrTiO3 films that allow the separate tailoring of nanoscale ionic and electronic channels at high density (∼1012 inch−2). We systematically show that these devices allow precise engineering of the resistance states, thus enabling large on–off ratios and high reproducibility. The tunable structure presents an ideal platform to explore ionic and electronic mechanisms and we expect a wide potential impact also on other nascent technologies, ranging from ionic gating to micro-solid oxide fuel cells and neuromorphics., Metal oxide resistive switches rely on the migration of oxygen vacancies and electrons under applied voltage. Here, Cho et al. use nanocomposites to control the electronic and ionic conductivities in spatially distinct channels, and fabricate memristors with high on/off ratios and reproducibility.

We demonstrate selective growth of ZnO branched nanostructures: from nanorod clusters (with branches parallel to parent rods) to nanotrees (with branches perpendicular to parent rods). The growth of these structures was realized using a three-step approach: electrodeposition of nanorods (NRs), followed by the sputtering of ZnO seed layers, followed by the growth of branched arms using hydrothermal growth. The density, size and direction of the branches were tailored by tuning the deposition parameters. To our knowledge, this is the first report of control of branch direction. The photoelectrochemical (PEC) performance of the ZnO nanostructures follows the order: nanotrees (NTs) > nanorod clusters (NCs) > parent NRs. The NT structure with the best PEC performance also possesses the shortest fabrication period which had never been reported before. The photocurrent of the NT and NC photoelectrodes is 0.67 and 0.56 mA cm-2 at 1 V vs. Ag/AgCl, respectively, an enhancement of 139% and 100% when compared to the ZnO NR structures. The key reason for the improved performance is shown to be the very large surface-to-volume ratios in the branched nanostructures, which gives rise to enhanced light absorption, improved charge transfer across the nanostructure/electrolyte interfaces to the electrolyte and efficient charge transport within the material.

We report on spontaneously phase ordered heteroepitaxial SrTiO3 (STO):ZnFe2O4 (ZFO) nanocomposite films that give rise to strongly enhanced photoelectrochemical solar water oxidation, consistent with enhanced photoinduced charge separation. The STO:ZFO nanocomposite yielded an enhanced photocurrent density of 0.188 mA/cm2 at 1.23 V vs a reversible hydrogen electrode, which was 7.9- and 2.6-fold higher than that of the plain STO film and ZFO film cases under 1-sun illumination, respectively. The photoelectrode also produced stable photocurrent and Faradaic efficiencies of H2 and O2 formation that were more than 90%. Incident-photon-to-current-conversion efficiency measurements, Tauc plots, Mott–Schottky plots, and electrochemical impedance spectroscopy measurements proved that the strongly enhanced photogenerated charge separation resulted from vertically aligned pseudosingle crystalline components, epitaxial heterojunctions, and a staggered band alignment of the components of the nanocomposite films. This study presents a completely new avenue for efficient solar energy conversion applications.

We report a method for synthesizing quasi-single crystal mesoporous ZnO nanostructuresvia a self-generated templating approach. ZnO–carbonaceous species nanocomposites (average diameter of ∼500 nm) were synthesized using a microwave-assisted hydrothermal reaction. The nanocomposites consisted of quasi-single crystalline ZnO regions and amorphous carbonaceous regions, which formed a self-generated nanotemplate. These nanocomposites were converted into quasi-single crystalline mesoporous ZnO nanostructures during combustion of the amorphous carbonaceous species (the template removing step). The adsorption properties and photocatalytic activities of the mesoporous ZnO structures were evaluated. The mesoporous ZnO structures showed better adsorption than the commercial ZnO nanostructures with similar dimensions or the 3D ZnO structures composed of nanoplates with {20} planar surfaces (benchmark materials) even though the BET surface area of the 3D ZnO structures was larger than that of the mesoporous ZnO structures. The quasi-single crystal mesoporous ZnO structures exhibited a high photocatalytic activity.

We report a method for synthesizing zinc aluminum layered double hydroxide (ZnAl:LDH) nanostructures at room temperature. The ZnAl:LDH nanoplates could be converted into zinc aluminum mixed metal oxide (MMO) nanostructures by calcination in air. The crystalline nature and morphology of the MMO nanostructures could be tuned by varying the calcination temperature. At low calcination temperatures (450–650 °C), nanostructures were composed of crystalline ZnO regions and amorphous regions. The crystalline orientations of the ZnO crystal grains were almost identical throughout the nanostructure. At calcination temperatures above 750 °C, ZnAl2O4 crystal grains appeared and amorphous regions could not be found in MMO nanostructures. As the calcination temperature increased, the crystal grain size and surface roughness of MMO nanostructures increased. Calcination at 950 °C resulted in the formation of MMO nanoparticles. The optical properties of the MMO nanostructures were probed by UV–vis diffuse reflectance spectroscopy. The spectra varied depending on their dimensions and crystalline natures.

We report a method for synthesizing small-diameter ZnO nanorods at room temperature (20 °C), under normal atmospheric pressure (1 atm), and using a relatively short reaction time (1 h) by adding gallium salts to the reaction solution. The ZnO nanorods were, on average, 92 nm in length and 9 nm in diameter and were single crystalline in nature. Quantitative analyses revealed that gallium atoms were not incorporated into the synthesized nanocrystals. On the basis of the experimental results, we propose a mechanism for the formation of small-diameter ZnO nanorods in the presence of gallium ions. The optical properties were probed by UV–Vis diffuse reflectance spectroscopy. The absorption band of the small-diameter ZnO nanorods was blue-shifted relative to the absorption band of the ∼230 nm diameter ZnO nanorods (control samples). Control experiments demonstrated that the absence of metal ion-containing precipitants (except ZnO) at room temperature is essential, and that the ZnO nanorod diameter distributions were narrow for the stirred reaction solution and broad when prepared without stirring.

In this study, the d-serine ammonia lyase (dsdA) gene from Escherichia coli was evaluated as a selectable marker for maize transformation. Plants are incapable of utilizing the D-form of most amino acids, and d-serine has recently been demonstrated to be phytoinhibitory to plant growth. d-Serine ammonia lyase detoxifies d-serine via a substrate-specific reaction to pyruvate, ammonia, and water. d-Serine inhibits germination of isolated maize immature embryos and growth of embryogenic callus from wild-type plants at concentrations about approx. 2–15 mM. Transgenic plants were recovered in the presence of d-serine in tissue culture media with dsdA as the selection marker at efficiencies comparable to using a mutated acetohydroxy acid synthase selection marker gene and selection in the presence of imidazolinone herbicides. Immature embryos infected with an Agrobacterium strain containing an acetohydroxy acid synthase gene construct without dsdA did not yield any transgenic events on the selection medium with 10 mM d-serine, indicating that d-serine provided selection tight enough to prevent escapes. Molecular analysis confirmed the integration of the dsdA gene into the genome of the transgenic plants. No adverse phenotypes were observed in the greenhouse, and expression of the dsdA marker had no affect on agronomic characteristics or grain yield in multi-location field trials. Seed compositional analysis demonstrated no significant differences in the contents of seed protein, starch, fatty acids, fiber, phytic acid, and free amino acids between transgenic and non-transgenic control plants. These data indicate that the dsdA gene is properly expressed in maize and the d-serine ammonia lyase (DSDA) enzyme functions appropriately to metabolize d-serine during in vitro selection. Preliminary safety assessments indicated that no adverse affects would be expected if humans were exposed to the DSDA protein in the diet from an allergenicity or toxicity perspective. The dsdA gene in combination with phytoinhibitory levels of d-serine represents a new and effective selectable marker system for maize transformation.

Fusarium head blight (FHB), primarily caused by Fusarium graminearum, reduces grain yield and quality in barley. Resistance to FHB is partial and quantitatively inherited. Previously, major FHB resistant QTL were detected on barley chromosome 2H Bin 8 and 2H Bin 10, and another QTL for reduced deoxynivalenol (DON) accumulation was identified on chromosome 3H Bin 6. To develop an understanding of the molecular responses controlled by these loci, we examined DON and fungal biomass levels and the transcriptome differences in near-isogenic line (NIL) pairs carrying contrasting resistant and susceptible alleles at these QTL during F. graminearum infection. No overlap was found among the differentially accumulated transcripts of the three NIL pairs, indicating that the response to infection controlled by the resistance alleles at each QTL may be distinct. Transcripts showing differential accumulation between resistant and susceptible NILs were compared to results from previous wheat/barley-F. graminearum studies and integrated into a wheat/barley-F. graminearum interaction model.

Cobos, Maria Jose/0000-0002-8636-1266; Millan, Teresa/0000-0003-1302-1794; Rubio, Josefa/0000-0002-5185-2719; Gil, Juan/0000-0001-7938-442X WOS: 000280780700004 A consensus genetic map of chickpea (Cicer arietinum L.) was constructed by merging linkage maps from 10 different populations, using STMS (Sequence-tagged Microsatellite Sites) as bridging markers. These populations derived from five wide crosses (C. arietinum x Cicer reticulatum) and five narrow crosses (Desi x Kabuli types) were previously used for mapping genes for several agronomic traits such as ascochyta blight, fusarium wilt, rust resistance, seed weight, flowering time and days to flower. The integrated map obtained from wide crosses consists of 555 loci including, among other markers, 135 STMSs and 33 cross-genome markers distributed on eight linkage groups and covers 652.67 cM. The map obtained from narrow crosses comprises 99 STMSs, 3 SCARs, 1 ASAP, fusarium resistance gene, 5 morphological traits as well as RAPD and ISSR markers distributed on eight linkage groups covering 426.99 cM. Comparison between maps from wide and narrow crosses reflects a general coincidence, although some discrepancies are discussed. Medicago truncatula cross-genome markers were BLASTed against the M. truncatula pseudogenome permitting assignments of chickpea linkage groups LGI, II, III, IV, V and VI on Medicago chromosomes 2, 5, 7, 1, 3 and 4, respectively. A marker detectable on Medicago chromosome 4 were also located on LGVIII, This consensus map is an important progress to assist breeders for selecting suitable markers to be used in marker-assisted selection (MAS). European Union (GLIP)European Union (EU) [FOOD-CT-2004-506223] The authors appreciate financial support from the European Union (GLIP FOOD-CT-2004-506223), and T.M. thanks for a GLIP fellowship.