Photo‐responsive lanthanide‐based single‐molecule magnets (SMM) hold great promise for future switching and memory devices. Herein, we report a dysprosium phosphonate DyIII(SCN)2(NO3)(depma)2(4‐hpy)2 ...(1Dy), which features a supramolecular framework containing layers of hydrogen‐bonding network and pillars of π–π interacted anthracene units. The photocycloaddition reaction of anthracene pairs led to a rapid and reversible single‐crystal‐to‐single‐crystal (SC–SC) structural transition to form the 1D coordination polymer DyIII(SCN)2(NO3)(depma2)(4‐hpy)2n (2Dy), accompanied by photoswitchable SMM properties with the reduction of effective energy barrier by half and the narrowing of the butterfly‐like hysteresis loop. The diluted sample showed a photo‐induced switch of the blocking temperature (TB) from 3.8 K for 1Dy@Y to 2.6 K for 2Dy@Y. This work may inspire the construction of lanthanide‐based molecular materials with targeted photo‐responsive magnetic properties.
A reversible photo‐induced single‐crystal‐to‐single‐crystal structural transformation was achieved for a mononuclear dysprosium‐anthracene compound to form a 1D coordination polymer. This compound displays photoswitchable SMM properties with reduced effective spin‐reversal energy barrier, narrowed butterfly‐like hysteresis loop, and decreased blocking temperature.
To develop superior rice varieties with improved yield in most rainfed areas of Asia/Africa, we started an introgression-breeding program for simultaneously improving yield and tolerances of multiple ...abiotic stresses. Using eight BC1 populations derived from a widely adaptable recipient and eight donors plus three rounds of phenotypic selection, we developed 496 introgression lines (ILs) with significantly higher yield under drought, salt and/or non-stress conditions in 5 years. Six new varieties were released in the Philippines and Pakistan and many more are being evaluated in multi-location yield trials for releasing in several countries. Marker-facilitated genetic characterization revealed three interesting aspects of the breeding procedure: (1) the donor introgression pattern in specific BC populations was characteristic; (2) introgression frequency in different genomic regions varied considerably, resulting primarily from strong selection for the target traits; and (3) significantly lower heterozygosity was observed in BC progenies selected for drought and salinity tolerance. Applying strong phenotypic selection under abiotic stresses in early segregating generations has major advantages for not only improving multiple abiotic stress tolerance but also achieving quicker homozygosity in early generations. This breeding procedure can be easily adopted by small breeding programs in developing countries to develop high-yielding varieties tolerant of abiotic stresses. The large set of trait-specific ILs can be used for genetic mapping of genes/QTL that affect target and non-target traits and for efficient varietal development by designed QTL pyramiding and genomics-based recurrent selection in our Green Super Rice breeding technology.
A new azo-complex (L)Cu(II)(NO3) L = (E)-3-(pyridin-2-yldiazenyl)naphthalen-2-ol (HL), was prepared via a one-pot synthetic method at 60 °C and was structurally characterized by IR, EA, PXRD and ...single crystal X-ray diffraction. In addition, TGA studies indicated that the complex was stable in air. The redox properties were determined by cyclic voltammetry, which revealed that the complex could be utilized as a catalyst for water oxidation under mild conditions. Subsequently, the complex was employed as a catalyst to take part in water oxidation reaction in the presence of a Ce(IV) salt utilized as an oxidant at pH 11 in PBS (Phosphate Buffered Saline) solution. The results suggested that the catalyst exhibited a high stability and activity toward water oxidation reaction under these conditions with an initial TOF of 4.0 kPa h(-1). Calculation methodology was performed to study the mechanism of the reaction, which revealed that in this catalytic process, the initial oxidation of Cu(II) to Cu(III) occurred by the formation of an intermediate "Cu(III)-O-O-Cu(III)". The formation of this intermediate, resulted in a release of oxygen and closing of the catalytic cycle.
By incorporating photoreactive anthracene moieties into binuclear Dy2O2 motifs, we obtain two new compounds with the formulas Dy2(SCN)4(L)2(dmpma)4 (1) and Dy2(SCN)4(L)2(dmpma)2(CH3CN)2 (2), where HL ...is 4-methyl-2,6-dimethoxyphenol and dmpma is dimethylphosphonomethylanthracene. Compound 1 contains face-to-face π–π interacted anthracene groups that meet the Schmidt rule for a 4 + 4 photocycloaddition reaction, while stacking of the anthracene groups in compound 2 does not meet the Schmidt rule. Compound 1 undergoes a reversible single-crystal-to-single-crystal structural transformation upon UV-light irradiation and thermal annealing, forming a one-dimensional coordination polymer of Dy2(SCN)4(L)2(dmpma)2(dmpma2) n (1UV). The process is concomitant with changes in the magnetic dynamics and photoluminescent properties. The spin-reversal energy barrier is significantly increased from 1 (55.9 K) to 1UV (116 K), and the emission color is changed from bright yellow for 1 to weak blue for 1UV. This is the first binuclear lanthanide complex that exhibits synergistic photocontrollable magnetic dynamics and photoluminescence. Ab initio calculations are conducted to understand the magnetostructural relationships of compounds 1, 1UV, and 2.
An effective combination reaction involved with sputtered and selenized Sb precursor was used for preparing Sb2Se3 thin film solar cells. Self-assembled growth of Sb2Se3 with large crystal grains, ...benign orientation, stoichiometric composition and high-quality heterojunction interface. A champion device with PCE of 6.15% is comparable to the state-of-the-art devices and represents the highest efficiency of sputtered Sb2Se3 solar cells.
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•An effective combination reaction of Sb metallic precursors for efficient Sb2Se3 solar cell.•Self-assembled growth of stoichiometric Sb2Se3 thin film with desired orientation.•An over-thick MoSe2 interfacial layer could be effectively suppressed.•The highest PCE of 6.15% in sputtered Sb2Se3 thin film solar cell with excellent stability.
Sputtering followed by post annealing is extensively used for fabrication of copper indium gallium selenide (CIGS), copper zinc tin sulfide (CZTS) and copper zinc tin sulfur selenide (CZTSSe) thin film solar cells. In this work, Sb2Se3 as an emerging alternative absorber was fabricated by an effective combination reaction of annealing sputtered Sb metallic precursors under Se vapor. Self-assembled growth of Sb2Se3 thin films consist of large grains that across the whole films have been successfully fulfilled via this combination reaction. Sb2Se3 thin films with desired orientation, stoichiometric composition and high-quality Sb2Se3/CdS heterojunction could be achieved once a proper selenization scenario was employed. Further, by selecting Sb films as precursors, the thickness of interfacial MoSe2 located at the back-contact region can be well controlled, leading to a significant enhancement in fill factor (FF) of the devices. This is in good accordance with our DFT simulation results which demonstrated Se vapor would be prone to react with the Sb lattice thermodynamically and thus limiting the thickness of the MoSe2 layer. Finally, a champion Sb2Se3 thin film solar cell with power conversion efficiency of 6.15% was achieved, which represents the highest efficiency of sputtered Sb2Se3 solar cells.
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•A ultra-thin Pt intermediate layer to increase the free carrier density of the Sb2Se3 absorber effectively.•The newly formed PtSe2 is quite useful to reduce the oxygen contamination ...on the Sb2Se3 surface as well as the intrinsic deep defects within the bulk film.•A competitive efficiency of 7.49% for substrate structured Sb2Se3 thin-film solar cell.
Insufficient free carrier concentration (1013 cm−3) has been considered one of the main culprits limiting the photovoltaic performance of antimony triselenide (Sb2Se3) thin-film solar cells. In this work, a thin platinum (Pt) intermediate layer is introduced into the system to address this issue for untreated Sb2Se3 absorber films. PtSe2 formation has been found within the absorber which directly contributes to the increased carrier density. The built-in voltage and back contact of the device are found to be optimized thanks to the increased carrier density. Meanwhile, both the interfacial and bulk recombination of the device are simultaneously reduced by passivating detrimental defect states at the Sb2Se3/CdS interface and the bulk film after Pt intermediate layer introduction. As a result, the overall photovoltaic performance of the substrate structured Sb2Se3 thin-film solar cell has been effectively improved, leading to a competitive power conversion efficiency of 7.49 % for the champion device. This work demonstrates an effective strategy for overcoming the key challenge of further efficiency improvement of Sb2Se3 solar cells.
Metal-organic frameworks or coordination polymers showing interesting magnetic properties have attracted much attention. By using 4,4′-bipyridine (4,4′-bpy) as auxiliary ligand, three new cobalt ...phosphonates based on 1-naphthalene phosphonic acid (1-napH2) were assembled under hydrothermal conditions at different pH, namely, Co(1-napH)2(4,4′-bpy)2(H2O)2 (1), Co2(1-nap)2(4,4′-bpy) (2), and Co2(1-nap)2(4,4′-bpy)(H2O)·2H2O (3). Compound 1 has a 0D mononuclear structure, where the Co(II) ion has a distorted octahedral geometry and 4,4′-bpy serves as an unusual terminal ligand. A 2D layer structure is found in compound 2, where the ladder-like chains made up of corner-sharing CoO3N and PO3C tetrahedra are connected by 4,4′-bpy. Interestingly, compound 3 with similar chemical composition to 2 except additional water molecules shows a 3D open-framework structure, where undulating chains of corner-sharing CoO4N trigonal bipyramids and PO3C tetrahedra are cross-linked by 4,4′-bpy. Magnetic studies reveal that compound 1 exhibits field-induced slow magnetization relaxation, whereas compounds 2 and 3 show field-induced spin-flop behavior and paramagnetism, respectively.
pH-Controlled three new mixed-ligated cobalt phosphonates based on 1-naphthalene phosphonic acid show 0D mononuclear, 2D layer and 3D open-framework structure, respectively, which exhibit different magnetic properties. Display omitted
•Three new cobalt phosphonates based on 1-naphthalene phosphonic acid have been assembled at different pH, which have 0D, 2D and 3D structure, respectively.•Magnetic studies reveal that compound 1 exhibits field-induced slow magnetization relaxation, whereas compounds 2 and 3 show field-induced spin-flop behavior and paramagnetism, respectively.
Photo‐responsive lanthanide‐based single‐molecule magnets (SMM) hold great promise for future switching and memory devices. Herein, we report a dysprosium phosphonate DyIII(SCN)2(NO3)(depma)2(4‐hpy)2 ...(1Dy), which features a supramolecular framework containing layers of hydrogen‐bonding network and pillars of π–π interacted anthracene units. The photocycloaddition reaction of anthracene pairs led to a rapid and reversible single‐crystal‐to‐single‐crystal (SC–SC) structural transition to form the 1D coordination polymer DyIII(SCN)2(NO3)(depma2)(4‐hpy)2n (2Dy), accompanied by photoswitchable SMM properties with the reduction of effective energy barrier by half and the narrowing of the butterfly‐like hysteresis loop. The diluted sample showed a photo‐induced switch of the blocking temperature (TB) from 3.8 K for 1Dy@Y to 2.6 K for 2Dy@Y. This work may inspire the construction of lanthanide‐based molecular materials with targeted photo‐responsive magnetic properties.
A reversible photo‐induced single‐crystal‐to‐single‐crystal structural transformation was achieved for a mononuclear dysprosium‐anthracene compound to form a 1D coordination polymer. This compound displays photoswitchable SMM properties with reduced effective spin‐reversal energy barrier, narrowed butterfly‐like hysteresis loop, and decreased blocking temperature.
To understand the genetic basis of yield-related traits of rice, we developed 39 chromosome segment substitution lines (CSSLs) from a cross between an average-yielding japonica cultivar, Sasanishiki, ...as the recurrent parent and a high-yielding indica cultivar, Habataki, as the donor. Five morphological components of panicle architecture in the CSSLs were evaluated in 2 years, and 38 quantitative trait loci (QTLs) distributed on 11 chromosomes were detected. The additive effect of each QTL was relatively small, suggesting that none of the QTLs could explain much of the phenotypic difference in sink size between Sasanishiki and Habataki. We developed nearly isogenic lines for two major QTLs, qSBN1 (for secondary branch number on chromosome 1) and qPBN6 (for primary branch number on chromosome 6), and a line containing both. Phenotypic analysis of these lines revealed that qSBN1 and qPBN6 contributed independently to sink size and that the combined line produced more spikelets. This suggests that the cumulative effects of QTLs distributed throughout the genome form the major genetic basis of panicle architecture in rice.
A series of 4, 6-disubstituted pyrimidine based iridium(III) complexes (1-5), has been synthesized with a simple method. Single X-ray structural analyses were conducted on 5 to reveal their ...coordination arrangement. These complexes exhibit almost single peak emission with the peak wavelength located in the range of 468–505 nm and quantum yields of over 75%. The relationship between photophysical properties and the substituent nature of the complexes was discussed by density functional theory. Organic light-emitting diodes (OLEDs) were also fabricated using these complexes as dopants in 15 wt%. The green device based on 1 shows a maximum external quantum efficiency, current efficiency, and power efficiency of 9.7%, 46.5 cd A−1 and 29.0 lm W−1, respectively, while the blue device based on 5 exhibits an external quantum efficiency of up to 14.5%, peak luminance efficiency of 28.0 cd A−1 and power efficiency of 19.5 lm W−1. Moreover, the Commission Internationale de L'Eclairage (CIE) coordinates of 5 are (0.15, 0.30) which is closer to blue emission than that of FIrpic.
OLED based on blue phosphor 5 shows luminous efficiencies of 14.5%, 28.0 cd A−1 with CIE of (0.15, 0.30). Display omitted
•A series of 4, 6-disubstituted pyrimidine based iridium(III) complexes (1-5), has been easily synthesized.•Complex 5 emitted 468 nm light with 86% QY and 14.5% EQE with CIE of (0.15,0.30).•Unlike FIrpic, complex 5 has only one shoulder emission, which is very important for improving color purity.
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