Designing Advanced Electrolytes for High-Safety and Long-Lifetime Sodium-Ion Batteries via Anion-Cation Interaction Modulation.

Safety hazards caused by flammable electrolytes have been major obstacles to the practical application of sodium-ion batteries (SIBs). The adoption of nonflammable all-phosphate electrolytes can effectively improve the safety of SIBs; however, traditional low-concentration phosphate electrolytes are not compatible with carbon-based anodes. Herein, we report an anion-cation interaction modulation strategy to design low-concentration phosphate electrolytes with superior physicochemical properties. Tris(2,2,2-trifluoroethyl) phosphate (TFEP) is introduced as a cosolvent to regulate the ion-solvent-coordinated (ISC) structure through enhancing the anion-cation interactions, forming the stable anion-induced ISC (AI-ISC) structure, even at a low salt concentration (1.22 M). Through spectroscopy analyses and theoretical calculations, we reveal the underlying mechanism responsible for the stabilization of these electrolytes. Impressively, both the hard carbon (HC) anode and Na4Fe2.91(PO4)2(P2O7) (NFPP) cathode work well with the developed electrolytes. The designed phosphate electrolyte enables Ah-level HC//NFPP pouch cells with an average Coulombic efficiency (CE) of over 99.9% and a capacity retention of 84.5% after 2000 cycles. In addition, the pouch cells can operate in a wide temperature range (-20 to 60 °C) and successfully pass rigorous safety testing. This work provides new insight into the design of the electrochemically compatibility electrolyte for high-safety and long-lifetime SIBs.

LiNO3 -Based Electrolytes via Electron-Donation Modulation for Sustainable Nonaqueous Lithium Rechargeable Batteries.

LiPF6 as a dominant lithium salt of electrolyte is widely used in commercial rechargeable lithium-ion batteries due to its well-balanced properties, including high solubility in organic solvents, good electrochemical stability, and high ionic conductivity. However, it suffers from several undesirable properties, such as high moisture sensitivity, thermal instability, and high cost. To address these issues, herein, we propose an electron-donation modulation (EDM) rule for the development of low-cost, sustainable, and electrochemically compatible LiNO3 -based electrolytes. We employ high donor-number solvents (HDNSs) with strong electron-donation ability to dissolve LiNO3 , while low donor-number solvents (LDNSs) with weak electron-donation ability are used to regulate the solvation structure to stabilize the electrolytes. As an example, we design the LiNO3 -DMSO@PC electrolyte, where DMSO acts as an HDNS and PC serves as an LDNS. This electrolyte exhibits excellent electrochemical compatibility with graphite anodes, as well as the LiFePO4 and LiCoO2 cathodes, leading to stable cycling over 200 cycles. Through spectroscopy analyses and theoretical calculation, we uncover the underlying mechanism responsible for the stabilization of these electrolytes. Our findings provide valuable insights into the preparation of LiNO3 -based electrolytes using the EDM rule, opening new avenues for the development of advanced electrolytes with versatile functions for sustainable rechargeable batteries.

Aromatic Ketones as Mild Presodiating Reagents toward Cathodes for High-Performance Sodium-Ion Batteries.

Chemical presodiation (CP) is an effective strategy to enhance energy density of sodium ion batteries. However, the sodiation reagents reported so far are basically polycyclic aromatic hydrocarbons (PAHs) wth low reductive potential (~0.1 V vs. Na+ /Na), which could easily cause over-sodiation and structural deterioration of the presodiated cathodes. In this work, Aromatic ketones (AKs) are rationally designed as mild presodiating reagents by introducing a carbonyl group (C=O) into PAHs to balance the conjugated and inductive effect. As the representatives, two compounds 9-Fluorenoneb (9-FN) and Benzophenone (BP) manifest favorable equilibrium potential of 1.55 V and 1.07 V (vs. Na+ /Na), respectively. Note that 9-FN demonstrates versatile presodiating capability toward multiple Na uptake hosts (tunneled Na0.44 MnO2 , layered Na0.67 Ni0.33 Mn0.67 O2 , polyanionic Na4 Fe2.91 (PO4 )2 P2 O7 , Na3 V2 (PO4 )3 and Na3 V2 (PO4 )2 F3 ), enabling greatly improved initial charging capacity of the cathode to balance the irrevisible capacity of the anode. Our results indicate that the Aromatic ketones are competitive presodiating cathodic reagents for high-performance sodium-ion batteries, and will inspire more studies and application attempts in the future.

[Differential expression profile of microRNAs between human bone marrow mesenchymal stem cells and sweat gland-like cells].

OBJECTIVE: To explore the differential microRNAs (miRNAs) expression profiles between human bone marrow mesenchymal stem cells (hBM-MSCs) and sweat gland-like cells. METHODS: The hBM-MSCs were induced to differentiate into osteogenic and adipogenic cells by related osteogenic differentiation basal medium and adipogenic differentiation basal medium respectively. And the results were assayed by oil red O and alizarin red stains respectively. When reaching 70%-80% confluence, primarily cultured sweat gland cells were heat-shocked and co-cultured with hBM-MSCs by a Transwell plate to induce the differentiation of hBM-MSCs. After 10 days, the total RNAs of hBM-MSCs and sweat gland-like cells were extracted, purified, labeled, hybridized and analyzed for predicting miRNAs target genes separately. The microarray results were confirmed by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: There were 68 miRNAs of >double differentiation on expression level between hBM-MSCs and sweat gland-like cells. And 19 miRNAs were up-regulated and 49 miRNAs down-regulated. Moreover, there were 13 miRNAs with >5 folds of differential expression level between hBM-MSCs and sweat gland-like cells, including 5 up-regulated miRNAs (miRNA-132-3p, -4467, -4484, -146a-5p and -6126) and 8 down-regulated miRNAs (miRNA-708-5p, -138-5p, -6812-5p, -138-1-3p, -1281, -3157-3p, -4298 and -4459). There were 18 miRNAs related to regulation of the signaling pathways of sweat gland development, including nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase/extracellular regulated protein kinase (MAPK/Erk), Wnt/beta-Catenin (Wnt/ß-Catenin) and ectodysplasin-A1/ectodysplasin-A1 receptor (EDA/EDAR). The results of RT-PCR on miRNA-146a-5p and miRNA-6812-5p had a high concordance with the results of microarray. CONCLUSIONS: There are obvious differentiation miRNAs expression profiles between hBM-MSCs and sweat gland-like cells. And 13 miRNAs >5 folds of differential expression and 18 miRNAs related to sweat gland development may play essential roles in regulated differentiation of hBM-MSCs into sweat gland-like cells.

Revealing the structural chemistry in Na6-2xFex(SO4)3 (1.5 ≤ x ≤ 2.0) for low-cost and high-performance sodium-ion batteries.

Fe-based polyanionic sulfate materials are one of the most promising candidates for large-scale applications in sodium-ion batteries due to their low cost and excellent electrochemical performance. Although great achievements have been gained on a series of Na6-2xFex(SO4)3 (NFSO-x, 1.5 ≤ x ≤ 2.0) materials such as Na2Fe2(SO4)3, Na2Fe1.5(SO4)3, and Na2.4Fe1.8(SO4)3 for sodium storage, the phase and structure characteristics on these NFSO-x are still controversial, making it difficult to achieve phase-pure materials with optimal electrochemical properties. Herein, six NFSO-x samples with varied x are investigated via both experimental methods and density functional theory calculations to analyze the phase and structure properties. It reveals that a pure phase exists in the 1.6 ≤ x ≤ 1.7 region of the NFSO-x, and part of Na ions tend to occupy Fe sites to form more stable frameworks. The NFSO-1.7 exhibits the best electrochemical performance among the NFSO-x samples, delivering a high discharge capacity (104.5 mAh g-1 at 0.1 C, close to its theoretical capacity of 105 mAh g-1), excellent rate performance (81.5 mAh g-1 at 30 C), and remarkable cycle stability over 10,000 cycles with high-capacity retention of 72.4%. We believe that the results are useful to clarify the phase and structure characteristics of polyanionic materials to promote their application for large-scale energy storage.

Ion-Migration Mechanism: An Overall Understanding of Anionic Redox Activity in Metal Oxide Cathodes of Li/Na-Ion Batteries.

The anionic redox reaction (ARR) has attracted extensive attention due to its potential to enhance the reversible capacity of cathode materials in Li/Na-ion batteries (LIBs/SIBs). However, the understanding of its activation mechanism is still limited by the insufficient mastering of the underlying thermodynamics and kinetics. Herein, a series of Mg/Li/Zn-substituted Nax MnO2 and Lix MnO2 cathode materials are designed to investigate their ARR behaviors. It is found that the ARR can be activated in only Li-substituted Lix MnO2 and not for Mg- and Zn-substituted ones, while all Mg/Li/Zn-substituted Nax MnO2 cathode materials exhibit ARR activities. Combining theoretical calculations with experimental results, such a huge difference between Li and Na cathodes is closely related to the migration of substitution ions from the transition metal layer to the alkali metal layer in a kinetic aspect, which generates unique Li(Na)-O-□TM and/or □Li/ Na -O-□TM configurations and reducing reaction activation energy to trigger the ARR. Based on these findings, an ion-migration mechanism is proposed to explain the different ARR behaviors between the Nax MnO2 and Lix MnO2 , which can not only reveal the origin of ARR in the kinetic aspect, but also provide a new insight for the development of high-capacity metal oxide cathode materials for LIBs/SIBs.

Efficient and Facile Electrochemical Process for the Production of High-Quality Lithium Hexafluorophosphate Electrolyte.

The global consumption for lithium hexafluorophosphate (LiPF6) has increased dramatically with the rapid growth of Li-ion batteries (LIBs) for large-scale electric energy storage applications. Conventional LiPF6 production has a high cost and high energy consumption due to complicated separation and purification processes. Here, based on the electrode materials of LiMn2O4 and polyaniline (PANI), we propose a facile electrochemical extraction/release process for LiPF6 electrolyte production. This new technology consists of two independent steps: a PF6-- and Li+-extracting step using a PANI/LixMn2O4 cell in aqueous solution (an ion extraction step) and a LiPF6 electrolyte production step from the charged LiMn2O4/PANI+PF6- cell in an organic electrolyte (an ion release step). This new process can effectively avoid the contamination of HF residue in the final product, providing a great possibility to create a facile, energy-efficient, and low-cost LiPF6 electrolyte production.

Highly Selective and Pollution-Free Electrochemical Extraction of Lithium by a Polyaniline/Lix Mn2 O4 Cell.

Conventional lithium extraction processes are inefficient or inadaptable for application in salt-lake brines with high Mg/Li ratios of ≥6. A new electrochemical cell, polyaniline (PANI)/Lix Mn2 O4 , was proposed to solve this problem for selective recovery of Li+ ions from brine water with high impurity cations (K+ , Na+ , Mg2+ , etc). Benefiting from the unique selectivity of spinel Lix Mn2 O4 for Li+ insertion and the high capacity of the PANI polymer for Cl- doping, this PANI/Lix Mn2 O4 cell could simultaneously extract LiCl from a simulated brine with a high average current efficiency of 95 %, an energy consumption of 3.95 W h molLiCl -1 , and a strong cycle ability with 70.8 % capacity retention over 200 cycles. In particular, this method avoids the use of additional chemicals, offering a highly efficient, pollution-free technology for Li+ extraction from brine waters.

A Membrane-Free and Energy-Efficient Three-Step Chlor-Alkali Electrolysis with Higher-Purity NaOH Production.

Conventional chlor-alkali processes are energy-consuming and environmentally unfriendly. To deal with this problem, we developed a three-step electrolysis (TSE) for a cleaner, energy-saving, and lower-cost chlor-alkali process. This new chlor-alkali process consists of three independent steps: a NaOH-production step in a Na0.44MnO2/oxygen-depolarizing cathode cell (step I), a Na+ and CI- extraction step in a Ag/Na0.44-xMnO2 cell (step II), and a CI2-production step in a graphite/AgCl cell (step III). This technology avoids the use of expensive ion-exchange membrane and toxic electrode materials, providing a great prospect to create a cleaner, energy-saving, and lower-cost chlor-alkali electrolysis process. This electrochemical ion coupling/decoupling technology can also be extended to other salt solutions (Na2SO4/NaNO3) to produce corresponding alkali (NaOH) and acid (H2SO4/HNO3), which has potential significance in the chlor-alkali industry.

Regenerative and reparative effects of human chorion-derived stem cell conditioned medium on photo-aged epidermal cells.

Epidermal cells are an important regenerative source for skin wound healing. Aged epidermal cells have a low ability to renew themselves and repair skin injury. Ultraviolet (UV) radiation, particularly UVB, can cause photo-aging of the skin by suppressing the viability of human epidermal cells. A chorion-derived stem cell conditioned medium (CDSC-CNM) is thought to have regenerative properties. This study aimed to determine the regenerative effects of CDSC-CNM on UVB-induced photo-aged epidermal cells. Epidermal cells were passaged four times and irradiated with quantitative UVB, and non-irradiated cells served as a control group. Cells were then treated with different concentrations of CDSC-CNM. Compared to the non-irradiated group, the proliferation rates and migration rates of UVB-induced photo-aged epidermal cells significantly decreased (p < 0.05) with increasing intracellular radical oxygen species (ROS) generation and DNA damage. After treatment with CDSC-CNM, photo-aged epidermal cells significantly improved their viability, and their ROS generation and DNA damage decreased. The secretory factors in CDSC-CNM, including epidermal growth factor (EGF), transforming growth factor-ß (TGF-ß), interleukin (IL)-6, and IL-8 and the related signaling pathway protein levels, increased compared to the control medium (CM). The potential regenerative and reparative effects of CDSC-CNM indicate that it may be a candidate material for the treatment of prematurely aged skin. The functions of the secretory factors and the mechanisms of CDSC-CNM therapy deserve further attention.

Overexpression of cyclin D1 induces the reprogramming of differentiated epidermal cells into stem cell-like cells.

It has been reported that Wnt/ß-catenin is critical for dedifferentiation of differentiated epidermal cells. Cyclin D1 (CCND1) is a ß-catenin target gene. In this study, we provide evidence that overexpression of CCND1 induces reprogramming of epidermal cells into stem cell-like cells. After introducing CCND1 gene into differentiated epidermal cells, we found that the large flat-shaped cells with a small nuclear-cytoplasmic ratio changed into small round-shaped cells with a large nuclear-cytoplasmic ratio. The expressions of CK10, ß1-integrin, Oct4 and Nanog in CCND1 induced cells were remarkably higher than those in the control group (P < 0.01). In addition, the induced cells exhibited a high colony-forming ability and a long-term proliferative potential. When the induced cells were implanted into a wound of laboratory animal model, the wound healing was accelerated. These results suggested that overexpression of CCND1 induced the reprogramming of differentiated epidermal cells into stem cell-like cells. This study may also offer a new approach to yield epidermal stem cells for wound repair and regeneration.