Hydrophobic Carbon Nitride Nanolayer Enables High-Flux Oil/Water Separation with Photocatalytic Antifouling Ability.

Efficient oil/water separation tackles various issues in occasions of oil leakage and oil discharge, such as environmental pollution, recollection of the oil, and saving the water. Herein, a compact superhydrophobic/superoleophilic graphitic carbon nitride nanolayer coated on carbon fiber networks (CNBA/CF) is designed and synthesized for efficient gravity-driven oil/water separation. The CNBA/CF shows excellent oil absorption and an impressive oil/water filtration separation performance. The flux reaches the state-of-art value of 4.29 × 105 L/m2/h for dichloromethane with separation efficiency up to 99%. Successive oil absorption tests, long-term filtration separation, and harsh conditions experiments confirm the remarkable separation and chemical structure stability of the CNBA/CF filter. Besides, the CNBA/CF demonstrates good photocatalytic antifouling ability thanks to the extended visible light absorption and improved charge separation. This work combines the material surface wettability modulation with a photocatalytic self-cleaning property in the fabrication of efficient oil/water separation materials while overcoming the filter fouling issue.

Optimizing the Spatial Density of Single Co Sites via Molecular Spacing for Facilitating Sustainable Water Oxidation.

Advances in single-atom (-site) catalysts (SACs) provide a new solution of atomic economy and accuracy for designing efficient electrocatalysts. In addition to a precise local coordination environment, controllable spatial active structure and tolerance under harsh operating conditions remain great challenges in the development of SACs. Here, we show a series of molecule-spaced SACs (msSACs) using different acid anhydrides to regulate the spatial density of discrete metal phthalocyanines with single Co sites, which significantly improve the effective active-site numbers and mass transfer, enabling one of the msSACs connected by pyromellitic dianhydride to exhibit an outstanding mass activity of (1.63 ± 0.01) × 105 A·g-1 and TOFbulk of 27.66 ± 1.59 s-1 at 1.58 V (vs RHE) and long-term durability at an ultrahigh current density of 2.0 A·cm-2 under industrial conditions for oxygen evolution reaction. This study demonstrates that the accessible spatial density of single atom sites can be another important parameter to enhance the overall performance of catalysts.

Self-Supporting Co/CeO2 Heterostructures for Ampere-Level Current Density Alkaline Water Electrolysis.

Remodeling the active surface through fabricating heterostructures can substantially enhance alkaline water electrolysis driven by renewable electrical energy. However, there are still great challenges in the synthesis of highly reactive and robust heterostructures to achieve both ampere-level current density hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a new Co/CeO2 heterojunction self-supported electrode for sustainable overall water splitting. The self-supporting Co/CeO2 heterostructures required only low overpotentials of 31.9 ± 2.2, 253.3 ± 2.7, and 316.7 ± 3 mV for HER and 214.1 ± 1.4, 362.3 ± 1.9, and 400.3 ± 3.7 mV for OER at 0.01, 0.5, and 1.0 A·cm-2, respectively, being one of the best Co-based bifunctional electrodes. Electrolyzer constructed from this electrode acting as an anode and cathode merely required cell voltages of 1.92 ± 0.02 V at 1.0 A·cm-2 for overall water splitting. Multiple characterization techniques combined with density functional theory calculations disclosed the different active sites on the anode and cathode, and the charge redistributions on the heterointerfaces that can optimize the adsorption of H and oxygen-containing intermediates, respectively. This study presents the tremendous prospective of self-supporting heterostructures for effective and economical overall water splitting.

Two-dimensional metal-phase layered molybdenum disulfide for electrocatalytic hydrogen evolution reaction.

The two-dimensional (2D) basal plane of metal-phase molybdenum disulphide (1T-MoS2) provides a large area of active sites to significantly reduce the overpotential of the hydrogen evolution reaction (HER), but the long preparation period limits its industrial application. Here, 1T-MoS2 catalysts derived from molybdenum blue solution (MBS) were prepared in one step using a rapid high-pressure microwave (MW-MoS2) strategy. This method eliminated the thermodynamic process with a long time required for Mo-O trioxide bond breakage and reduction (MoVI → MoIV) of the conventional hydrothermal method. Additionally, the introduction of heteroatomic oxygen atoms effectively reduced the build-up of MW-MoS2 and improved the monolayer/few-layer state and stability. Impressively, MW-MoS2 has outstanding electrocatalytic performance, with a low overpotential (62 mV) at 10 mA cm-2 and a small Tafel slope (42 mV dec-1). This provides a simple strategy for the rapid preparation of a 2D sulphide HER catalyst with performance close to that of commercial Pt/C.

A Metal-Organic Frameworks Derived 1T-MoS2 with Expanded Layer Spacing for Enhanced Electrocatalytic Hydrogen Evolution.

Metal phase molybdenum disulfide (1T-MoS2 ) is considered a promising electrocatalyst for hydrogen evolution reaction (HER) due to its activated basal and superior electrical conductivity. Here, a one-step solvothermal route is developed to prepare 1T-MoS2 with expanded layer spacing through the derivatization of a Mo-based organic framework (Mo-MOFs). Benefiting from N,N-dimethylformamide oxide as external stress, the interplanar spacing of (002) of the MoS2 catalyst is extended to 10.87 Å, which represents the largest one for the 1T-MoS2 catalyst prepared by the bottom-up approach. Theoretical calculations reveal that the expanded crystal planes alter the electronic structure of 1T-MoS2 , lower the adsorption-desorption potentials of protons, and thus, trigger efficient catalytic activity for HER. The optimal 1T-MoS2 catalyst exhibits an overpotential of 98 mV at 10 mA cm-2 for HER, corresponding to a Tafel slope of 52 mV dec-1 . This Mo-MOFs-derived strategy provides a potential way to design high-performance catalysts by adjusting the layer spacing of 2D materials.

Clear-Box Machine Learning for Virtual Screening of 2D Nanozymes to Target Tumor Hydrogen Peroxide.

Targeting tumor hydrogen peroxide (H2 O2 ) with catalytic materials has provided a novel chemotherapy strategy against solid tumors. Because numerous materials have been fabricated so far, there is an urgent need for an efficient in silico method, which can automatically screen out appropriate candidates from materials libraries for further therapeutic evaluation. In this work, adsorption-energy-based descriptors and criteria are developed for the catalase-like activities of materials surfaces. The result enables a comprehensive prediction of H2 O2 -targeted catalytic activities of materials by density functional theory (DFT) calculations. To expedite the prediction, machine learning models, which efficiently calculate the adsorption energies for 2D materials without DFT, are further developed. The finally obtained method takes advantage of both interpretability of physics model and high efficiency of machine learning. It provides an efficient approach for in silico screening of 2D materials toward tumor catalytic therapy, and it will greatly promote the development of catalytic nanomaterials for medical applications.

Cu-Modified La2Si2O7/TiO2 composite materials: preparation, characterization and photothermal properties.

Cu-Modified La2Si2O7/TiO2 composite materials were prepared by the molten salt method and a solid-phase reduction strategy. Due to the surface plasmon resonance (SPR) of copper, the optical response from the UV to the visible region and near-infrared is increased. In the meantime, it enhances the absorption of visible light by the titanium dioxide and acts as a plasma catalyst. The combination enhances the photothermal properties of the composite. The particle size of Cu/La2Si2O7/TiO2 is in the range of 100 to 230 nm. Results show that the composite has a good photothermal effect. The 1 mg ml-1 solution can be warmed up to 63.1 °C at 0.5 W cm-2 laser power density with a maximum temperature difference of 45 °C. It has potential applications in solar energy conversion, photothermal catalysis, etc.

Transcriptome analyses of potential regulators of pre- and post-ovulatory follicles in the pigeon (Columba livia).

To identify the dominant genes controlling follicular maturation, ovulation and regression for pigeon, we used RNA-seq to explore the gene expression profiles of pre- and post-ovulatory follicles of pigeon. We obtained total of 4.73million (96% of the raw data) high-quality clean reads, which could be aligned with 20282 genes. Gene expression profile analysis identified 1461 differentially expressed genes (DEGs) between the pre- (P4) and post-ovulatory follicles (P5). Of these, 843 genes were upregulated, and 618 genes were down-regulated. Furthermore, many DEGs were significantly enriched in some pathways closely related to follicle maturation, ovulation and regression, such as ECM-receptor interaction, vascular smooth muscle contraction, progesterone-mediated oocyte maturation, phagosome. Importantly, the DGEs in ECM-receptor interaction pathway included COL1A1 , COL1A2 , COL4A1 , COL4A2 , ITGA11 , ITGB3 and SDC3 , in the progesterone-mediated oocyte maturation pathway involved CDK1 , CDC25A , CCNB3 , CDC20 and Plk1 , and in the vascular smooth muscle contraction covered CALD1 , KCNMA1 , KCNMB1 , CACNA1 , ACTA2 , MYH10 , MYL3 , MYL6 , MYL9 , closely related to promoting follicular maturation and ovulation in pre-ovulatory follicles. Moreover, it seems that the lysosomal cathepsin family has a decisive role in the regression of early stage of post-ovulatory follicle. Taken together, these data enrich the research of molecular mechanisms of pigeon follicular activities at the transcriptional level and provide novel insight of breeding-related physiology for birds.

Combining functional hairpin probes with disordered cleavage of CRISPR/Cas12a protease to screen for B lymphocytic leukemia.

One of the causes of B lymphocytic leukemia is abnormal expression of the Pax-5a gene. Detection of the Pax-5a gene can provide effective technical means for early screening of B lymphocytic leukemia. In this work, we designed a sensing scheme to detect the Pax-5a gene based on the signal amplification system, which is based on dual-enzyme assisted target gene circulation, and the disordered cleavage of CRISPR/Cas12a protease. The hairpin probe (HP) in this scheme not only contains the binding sites of the target gene and the primer, but also cleverly contains half of the Nt.BbvCI splicing sites. When the target gene is present, through the synergistic effect of KF and Nt.BbvCI, a large number of single strands of a specific sequence can be produced. At the same time, the target gene falls off from the first hairpin and opens the other hairpin to realize the cycle of the target gene. The resulting single-strand can bind to the Cas12a/crRNA binary complex and unlock the anti-cleavage activity of the CRISPR/Cas12a protease. The single strands labeled with the fluorescent group (FAM) and the quenching group (BHQ) around the solution are cleaved, the fluorescence signal of FAM is restored, and a detectable fluorescence signal is generated. The detection limit is as low as 6.77 fM, and the target gene and the mismatch sequence can also be distinguished well. Therefore, the sensing scheme provides a new detection direction for the early diagnosis and screening of B lymphocytic leukemia.

Transcriptome analyses to reveal the dynamic change mechanism of pigeon magnum during one egg-laying cycle.

We analyzed the transcriptome of pigeon magnum in three stages (C1: pre-ovulation, C2: post-ovulation, C3: 5-6 days after ovulation) to elucidate the molecular and cellular events associated with morphological changes during the laying cycle. We observed that C1 was highly developed, apoptosis rate was highest in C2, and C3 attained the smallest size. Through RNA-sequencing, we obtained 54,764,938 (97.2%) high-quality clean reads that aligned to 20,767 genes. Gene expression profile analysis showed the greatest difference between C1 and C3; 3966 differentially expressed genes (DEGs) were identified, of which 2250 genes were upregulated and 1716 genes were downregulated in C1. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that protein processing and transport activities were prominent in C1, and upregulated genes included those related to signal recognition particle (SRP), signal recognition particle receptor (SRPR), translocon, GRP78, RRBP1, TRAP, TRAM1, and OST. Egg white protein-related gene expression was highest, with OVALY being the most highly expressed. In C2, apoptosis-related gene expression was higher than in C1, and fatty acid metabolism was active, which may be correlated with magnum tissue regression. Collagen- and laminin-related gene expression was prominent in C1 and C3, indicating roles in egg white protein generation and magnum reconstruction. PR gene expression was highest and exhibited drastic change in the three groups, indicating that PR and its regulation may be involved in changes in magnum morphology and function. Through the identification and functional analysis of DEGs and other crucial genes, this may contribute to understand the egg white protein production, magnum tissue regression, and magnum regeneration mechanisms.

Scandium Molybdate Microstructures with Tunable Phase and Morphology: Microwave Synthesis, Theoretical Calculations, and Photoluminescence Properties.

In this paper, scandium molybdate microstructures have been prepared from solution via a microwave heating method. By controlling the experimental parameters such as molar ratio of reagent and reaction time, scandium molybdates with tunable phase and diverse morphologies including snowflakes, microflowers, microsheets, and branched spindles were obtained. The density of states and surface energies of Sc2Mo3O12 were primarily studied from first-principles calculations. An indirect band gap of 3.56 eV was observed for crystalline Sc2Mo3O12, and the surface energies of various facets were determined to be 0.27-0.91 J/m2. The influence of n(Sc3+): n(Mo7O246-) (short for Sc/Mo) molar ratio was systematically investigated and well-characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and UV-vis absorption spectroscopy (UV-vis). Results indicate that the Sc/Mo molar ratio has a great effect on the phase and morphology. Diffuse reflection spectra (DRS) revealed the Egap can be readily tuned from 3.69 to 4.16 eV, which is in accordance with the theoretical result. The photoluminescence (PL) properties of Eu3+-doped Sc2Mo3O12 were discussed. This facile synthesis strategy could be extended to the synthesis of other molybdates.

Ultrahigh luminescence quantum yield lanthanide coordination polymer as a multifunctional sensor.

The investigation and development of advanced multifunctional and sensitive sensors with high luminescent quantum yield and the capability of detecting different analytes, such as metal ions, is imperative. Due to its inherent properties the lanthanide coordination complex is one candidate for sensing applications, particularly for multifunctional sensors. Herein, we present two series of alkali ion decorated lanthanide coordination polymers (Ln-CPs), which show ultrahigh luminescence quantum yields (QYs) of 77% (1a) and 92% (2a). To the best of our knowledge, 1a represents the first trifunctional lanthanide complex sensor that can simultaneous detect and discriminate three different analytes, namely H+/Cd2+/Cr3+ through a multimode optical response. Furthermore, the limit of detection (LOD) for Cr3+ is an ultralow value of 2.0 × 10-9 M with a sensing time of 2 h, which is comparable to the most sensitive Cr3+ chemosensor. More interestingly, 92% (2a) is an unprecedented luminescence QY among the reported lanthanide coordination complexes.

Detailed structure information a highly thermostable Tb-cluster that based on a prodrug ligand of 2,4,5-trifluoro-3-methoxybenzoic acid.

In this brief data article, we present the precise structural information, PARD data and thermographic analysis of the Tb-cluster. Detailed structure, luminescence and detecting properties were discussed in our previous study (Zhao et al., 2017) [1]. The data includes the coordination modes of ligand, PXRD patterns of these Ln-MOFs, thermostability, detailed bond lengths and bond angles of the Tb-cluster.

Structural data of structure variation and luminescence of 3D, 2D and 1D lanthanide coordination polymers with 1,3-adamantanediacetic acid.

In this data article, we report the structure, Fourier transform infrared spectroscopy(FT-IR), powder X-ray diffraction (PARD), luminescence decay, thermogravimetric analysis (TGA) and UV-vis data of three series Ln-MOFs. Detailed structure and luminescence properties were discussed in our previous study (Zhao et al., 2018) [1]. The data includes the structure patterns of ligand H2ADA, FT-IR, PXRD and thermostability of Ln-MOFs in the air, detailed structure information for these structures are listed in Table 1, Table 2, Table 3, Table 4, Table 5, Table 6, Table 7.

Structural data of thermostable 3D Ln-MOFs that based on flexible ligand of 1,3-adamantanediacetic acid.

In this data article, we present the structural and PARD data of the Ln-MOFs. Detailed structure, luminescence and sensing properties were discussed in our previous study (Zeng et al., in press) [1] The data includes the SBU structure patterns of these Ln-MOFs, thermostability of Ln-MOFs in water and also detailed structure information listed in Table 1, Table 2, Table 3, Table 4, Table 5, Table 6, Table 7, Table 8.

Multi-shelled ceria hollow spheres with a tunable shell number and thickness and their superior catalytic activity.

In this work, ceria multi-shelled nanospheres with a tunable shell number and thickness were prepared by a facile coordination polymer (CP) precursor method without the use of any template and surfactant. Interestingly, the number, thickness and structure of the shell can be tuned by varying the reaction time, reaction temperature, ratio of reagent and calcination temperature. The formation process of the multi-shelled hollow spheres was also investigated, which experienced a core contraction and shell separation process. Moreover, the multi-shelled CeO2 hollow nanospheres displayed excellent photocatalytic activity in the degradation of RhB. Au and AuPd nanoparticle loaded multi-shelled CeO2 nanocomposites were also prepared. Results show that Au/CeO2 multi-shelled hollow nanospheres showed eximious catalytic activity for the reduction of p-nitrophenol with a reaction rate constant k of 0.416 min. In addition, AuPd/CeO2 exhibited a remarkable catalytic activity for the conversion of CO. Employing this method, heavy rare earth oxide multi-shelled structures and light rare earth oxide solid spheres were obtained. This method may be employed for the preparation of other materials with complex structures.

Uniform Cerium-Based Coordination Polymer Microsnheres: Preoaration and Upconversion Emission.

Homogeneously doped Yb3+ and Er3+ cerium-based coordination polymer (CP) microspheres have been successfully synthesized on a large scale through a simple solvothermal route with 2,5-pyridinedicarboxylic acid (2,5-H2PDC) as the organic linker. CeO2: Yb3+, Er3+ porous microspheres were obtained by annealing the corresponding CP microspheres at 600 °C for 4 h under atmospheric pressure. These as-prepared products were characterized by Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersion X-ray (EDX) spectroscopy, Thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis. The room temperature upconversion luminescent spectra of the as-prepared microspheres were carried out by 980 nm NIR light excitation. Interestingly, Yb3+ and Er3+ codoped CP microspheres give a single-band emission centered at 673 nm, while the CeO2: Yb3+, Er3+ microspheres give emission in green and red region, with red being the dominant emission. The emission intensity of the CeO2: Yb3+, Er3+ microspheres were much stronger than that of the Yb3+ and Er3+ codoped CP microspheres.

Transcriptomic analysis of different stages of pigeon ovaries by RNA-sequencing.

The pigeon ovary is an ideal model for deciphering the molecular mechanism of folliculogenesis. While most analysis has focused on the influence of hormones and factors on ovarian follicle development in this model, changes occurring in the ovarian stroma can also be extremely informative. Here, we profiled the transcriptome of pigeon ovaries at pre-ovulation, post-ovulation, and 5-6 days after ovulation using RNA-sequencing to gain insights into the molecular and cellular events mediating ovary activity. We obtained 44,784,505 clean reads that aligned with 14,088 genes. Gene expression profile analysis identified 409 differentially expressed genes between pre- and post-ovulation; 96 genes were up-regulated genes while 313 genes were down-regulated. Gene ontology analysis of the down-regulated genes revealed significant enrichment in components of the immune response, immune system, antigen processing and presentation, receptor binding, and biological adhesion. Pathway analyses of the high-expression genes of the post-ovulation ovary identified enrichment in phagosomes, lysosomes, cytokine-cytokine receptor interactions, cell adhesion molecules, and the Toll-like receptor signaling. These data together suggest that post-ovulatory follicle regression and elimination occurs through an immune response. Mol. Reprod. Dev. 83: 640-648, 2016. © 2016 Wiley Periodicals, Inc.

Lanthanide co-doped paramagnetic spindle-like mesocrystals for imaging and autophagy induction.

We synthesized two novel lanthanide doped spindle-like mesocrystals, YF3:Ce,Eu,Gd and YF3:Ce,Tb,Gd (abbreviated as YEG and YTG mesospindles, respectively). Both of them possess paramagnetic and fluorescent properties, and their excellent cyto-compatibility and low haemolysis are further confirmed. Therefore, they could act as dual mode contrast agents for magnetic resonance imaging (MRI) and fluorescence imaging. Furthermore, YEG and YTG mesospindles induce dose and time dependent autophagy by activating the PI3K signaling pathway. The autophagy induced by YEG and YTG mesocrystals is confirmed by enhanced autophagosome formation, normal cargo degradation, and no disruption of lysosomal function. This work is important to illustrate how rare-earth mesocrystals affect the autophagic pathway, indicating the potential of the YEG and YTG mesospindles in diagnosis and therapy.

Coordination polymer core/shell structures: Preparation and up/down-conversion luminescence.

Coordination polymer (CP) core-shell nanoparticles with Gd-based CP (GdCP) as core and Eu-based CP (EuCP) as shell have been successfully prepared. Allantoin was employed as the organic building block without the assistance of any template. The composition, size and structure of the core-shell nanospheres were well characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TG). Results show that the resultant cores are uniform nanospheres with diameter of approximately 45nm, while the diameters of the core-shell nanospheres are increased to approximately 60nm. The core-shell products show enhanced luminescence efficiency than the core under 980nm laser excitation and decreased down-conversion luminescence when excited at 394nm.