Fe-based air alkaline batteries are promising candidates for large scale energy storage due to their low cost, eco-friendliness and high energy density. In this work, pure iron was studied as ...negative electrode of Fe-air batteries with and without Na2S added to the KOH alkaline electrolyte in order to bring new insight on the mechanisms of inhibition of the hydrogen evolution reaction (HER) and improvement of the electrochemical performances of the Fe electrode. Electrochemical (CV, galvanostatic discharge), spectroscopic (XPS, ToF-SIMS) and microscopic (SEM) analysis were applied to characterize the effect of the sulfide additive (Na2S) on the electrochemical behavior of Fe electrodes and their chemical and morphological modifications. Surface analysis performed by XPS and ToF-SIMS revealed the formation of a markedly thicker oxide/hydroxide layer. The mechanism of formation of this thick oxide/hydroxide layer is initiated by the adsorption of sulfur (Sads) at the oxide/metal interface that inhibits the HER during the first stages of electrochemical process and promotes subsequent anodic oxidation. With the Na2S electrolyte additive, Fe(0)/Fe(II) conversion/deconversion is suppressed and charge/discharge proceeds mostly by Fe(II)/Fe(III) conversion/deconversion with improved capacity owing to the porous morphology of the oxide/hydroxide layer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Soil salinization has seriously affected agricultural production and ecological balance in the Yellow River Delta region. Rapid and accurate monitoring of soil salinity has become an urgent need. ...Traditional machine learning models tend to fall into local optimal values during the learning process, which reduces their accuracy. This paper introduces Circle map to enhance the crayfish optimization algorithm (COA), which is then integrated with the regularized extreme learning machine (RELM) model, aiming to improve the accuracy of soil salinity content (SSC) inversion in the Yellow River Delta region. We employed Landsat5 TM remote sensing images and measured salinity data to develop spectral indices, such as the band index, salinity index, vegetation index, and comprehensive index, selecting the optimal modeling variable group through Pearson correlation analysis and variable projection importance analysis. The back propagation neural network (BPNN), RELM, and improved crayfish optimization algorithm–regularized extreme learning machine (ICOA-RELM) models were constructed using measured data and selected variable groups for SSC inversion. The results indicate that the ICOA-RELM model enhances the R2 value by an average of about 0.1 compared to other models, particularly those using groups of variables filtered by variable projection importance analysis as input variables, which showed the best inversion effect (test set R2 value of 0.75, MAE of 0.198, RMSE of 0.249). The SSC inversion results indicate a higher salinization degree in the coastal regions of the Yellow River Delta and a lower degree in the inland areas, with moderate saline soil and severe saline soil comprising 48.69% of the total area. These results are consistent with the actual sampling results, which verify the practicability of the model. This paper’s methods and findings introduce an innovative and practical tool for monitoring and managing salinized soils in the Yellow River Delta, offering significant theoretical and practical benefits.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The electrochemical performance of ionic liquid electrolytes containing different sodium salts dissolved in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMPTFSI) evaluated in a ...half-cell configuration using spherical P2-Na0.6Co0.1Mn0.9O2+z (NCO) cathodes are reported. Among the various electrolytes investigated, sodium bis(fluorosulfonyl)imide (NaFSI) (0.5 M) in BMPTFSI shows the best electrochemical performance with a significant improvement in cycling stability (90% capacity retention after 500 cycles at 50 mA g–1 in a half cell versus Na metal anode) compared with conventional NaClO4 (1 M) in ethylene carbonate/propylene carbonate electrolytes (39% retention after 500 cycles). Cyclic voltammetry (CV) studies reveal that ionic liquid electrolytes are stable up to 4.8 V versus Na/Na+. When NaFSI and NaTFSI are used as conducting salts, X-ray photoelectron spectroscopy results prove that the cathode electrolyte interface (CEI) is composed of components resulting from the decomposition of the TFSI anion and the deposition of the BMP cation. On the other hand, the CEI layer of the electrode cycled in an electrolyte containing NaClO4 in BMPTFSI follows a different pathway of TFSI decomposition and consists mainly of sodium fluoride. Similarly, plating studies were used to understand the stability of different ionic liquids in contact with metallic sodium. It was found that the excellent capacity retention for the electrolyte consisting of NaFSI salt is related to the formation of a stable CEI and solid electrolyte interphase layers.
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IJS, KILJ, NUK, PNG, UL, UM
B-box (BBX) proteins are a type of zinc finger proteins containing one or two B-box domains. They play important roles in development and diverse stress responses of plants, yet their roles in wheat ...remain unclear.
In this study, 96 BBX genes were identified in the wheat genome and classified into five subfamilies. Subcellular localization prediction results showed that 68 TaBBXs were localized in the nucleus. Protein interaction prediction analysis indicated that interaction was one way that these proteins exerted their functions. Promoter analysis indicated that TaBBXs may play important roles in light signal, hormone, and stress responses. qRT-PCR analysis revealed that 14 TaBBXs were highly expressed in seeds compared with other tissues. These were probably involved in seed dormancy and germination, and their expression patterns were investigated during dormancy acquisition and release in the seeds of wheat varieties Jing 411 and Hongmangchun 21, showing significant differences in seed dormancy and germination phenotypes. Subcellular localization analysis confirmed that the three candidates TaBBX2-2 A, TaBBX4-2 A, and TaBBX11-2D were nuclear proteins. Transcriptional self-activation experiments further demonstrated that TaBBX4-2A was transcriptionally active, but TaBBX2-2A and TaBBX11-2D were not. Protein interaction analysis revealed that TaBBX2-2A, TaBBX4-2A, and TaBBX11-2D had no interaction with each other, while TaBBX2-2A and TaBBX11-2D interacted with each other, indicating that TaBBX4-2A may regulate seed dormancy and germination by transcriptional regulation, and TaBBX2-2A and TaBBX11-2D may regulate seed dormancy and germination by forming a homologous complex.
In this study, the wheat BBX gene family was identified and characterized at the genomic level by bioinformatics analysis. These observations provide a theoretical basis for future studies on the functions of BBXs in wheat and other species.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Here, in recent years, 2-D transition-metal dichalcogenides (TMDCs) have received great interests because of the broader possibilities offered by their tunable band gaps, as opposed to gapless ...graphene which precludes application in digital electronics. TMDCs exhibit an indirect-to-direct band gap transition at the single atomic sheet state as well as optically accessible spin degree of freedom in valleytronics.
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IJS, KILJ, NUK, PNG, UL, UM
Iron oxide (mostly α-Fe2O3) model thin-film electrodes were prepared by thermal oxidation of pure metal iron substrates at 300 ± 5 °C in air and used for comprehensive investigation of the ...lithiation/delithiation mechanisms of anode material undergoing an electrochemical conversion reaction with lithium ions. Surface (X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS)) and electrochemical (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)) analytical techniques were combined. The results show that intercalation of Li in the Fe2O3 matrix and solid electrolyte interphase (SEI) layer formation both precede conversion to metallic iron and Li2O upon lithiation. Depth profile analysis evidences stratification of the converted thin-film electrode into fully and partially lithiated outer and inner parts, respectively, due to mass transport limitation. The SEI layer has a stable composition (Li2CO3 with minor ROCO2Li) but dynamically increases/decreases in thickness upon lithiation/delithiation. Conversion, proceeding mostly in the outer part of the electrode, causes material swelling accompanied by SEI layer thickening. Upon delithiation, lithium is trapped in the deconverted electrode subjected to shrinking, and the SEI layer mostly decomposes and reduces in thickness after deconversion. The nonreversibility of both conversion and surface passivation mechanisms is demonstrated.
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IJS, KILJ, NUK, PNG, UL, UM
Porous photocatalysts are promising materials capable of simultaneously adsorbing and oxidizing/reducing target species, showing great potentials in environmental remediation and energy generation. ...This review offered a comprehensive overview of the recent progress in design, fabrication, and applications of porous photocatalysts, including carbon‐based semiconductors, metal oxides/sulfides, metal–organic frameworks, and adsorbent–photocatalyst hybrids. The fundamental understanding of the structure–performance relationships of porous materials together with the in‐depth insights into the synergetic effects between adsorption and photocatalysis was presented. The strategies to further improve the photocatalytic activity of porous photocatalysts were proposed. This review would provide references and outlooks of constructing efficient porous materials for adsorptive and photocatalytic removal of pollutants and energy production.
This review offers an overview on the recent progresses of design, fabrication, and applications of porous photocatalysts.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
As important ingredients in lithium‐ion battery, the Coulombic efficiency and power density greatly impact the electrochemical performances. Although recent literatures have reported nano‐porous ...materials to enhance the specific capacities, intrinsic drawbacks such as poor initial Coulombic efficiency and low volumetric capacity could not be avoided. Herein, we propose a strategy to prepare carbon supported MoO2 spheres used for lithium‐ion battery with high volumetric capacity density. A high initial Coulombic efficiency of 76.5% is obtained due to limited solid electrolyte interface film formed on the exposed surface. Meantime, the sample with an optimal carbon content and a proper structural strength reveals a higher reversible capacity of 956 mA h g−1 than the theoretical capacity of crystalline MoO2 (838 mA h g−1) and a high capacity retention ratio of 96.4% after 100 cycles at 0.5 A g−1. And an effective compaction capacity density (under 5 MPa) of 670 mA h cm−3 of the spheres proves its potential value in practical applications.
We propose a strategy to prepare carbon supported MoO2 spheres with a high initial Coulombic efficiency of 76.5% and a high capacity retention ratio of 96.4% after 100 cycles at 0.5 A g−1. And the compaction capacity density (under 5 MPa) of 670 mA h cm−3 of the spheres proves its potential value in practical applications.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We investigate black phosphorus by time- and angle-resolved photoelectron spectroscopy. The electrons excited by 1.57 eV photons relax down to a conduction band minimum within 1 ps. Despite the low ...band gap value, no relevant amount of carrier multiplication could be detected at an excitation density 3–6 × 1019 cm–3. In the thermalized state, the band gap renormalization is negligible up to a photoexcitation density that fills the conduction band by 150 meV. Astonishingly, a Stark broadening of the valence band takes place at an early delay time. We argue that electrons and holes with a high excess energy lead to inhomogeneous screening of near surface fields. As a consequence, the chemical potential is no longer pinned in a narrow impurity band.
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IJS, KILJ, NUK, PNG, UL, UM
► Li4Ti5O12/graphene composite is synthesized by a sol–gel method for the first time. ► The introduction of graphene can improve the capacity and cycling stability of Li4Ti5O12, especially at high ...current rates. ► Li4Ti5O12/graphene composite discharged to 0V exhibits a quite high capacity of 274mAhg−1 below 1.0V.
Li4Ti5O12/graphene composite was prepared by a facile sol–gel method. The lattice structure and morphology of the composite were investigated by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The electrochemical performances of the electrodes have been investigated compared with the pristine Li4Ti5O12 synthesized by a similar route. The Li4Ti5O12/graphene composite presents a higher capacity and better cycling performance than Li4Ti5O12 at the cutoff of 2.5–1.0V, especially at high current rate. The excellent electrochemical performance of Li4Ti5O12/graphene electrode could be attributed to the improvement of electronic conductivity from the graphene sheets. When discharged to 0V, the Li4Ti5O12/graphene composite exhibited a quite high capacity over 274mAhg−1 below 1.0V, which was quite beneficial for not only the high energy density but also the safety characteristic of lithium-ion batteries.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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