In-situ/operando characterization techniques in lithium-ion batteries and beyond

Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applications and novel devices constructed in recent years are necessary to be reviewed for inspiring subsequent studies.Hence,we summarize the progress of in-situ/operando techniques employed in rechargeable batteries.The members of this large family are divided into three sections for introduction,including bulk material,electrolyte/electrode interface and gas evolution.In each part,various energy-storage systems are mentioned and the related experimental details as well as data analysis are discussed.The simultaneous strategies of various in-situ methods are highlighted as well.Finally,current challenges and potential solutions are concluded towards the rising influence and enlarged appliance of in-situ/operando techniques in the battery research.

2D arsenenes

Graphene has raised a huge wave in 2D materials field,breeding lots of graphene analogs with applications in optical and electrical devices,energy conversion and storage,bio-logy,etc.[1,2].Graphene presents superior carrier mobility,while its zero-bandgap restricts its transistor application.To make up this shortcoming,new 2D materials with certain bandgaps and high carrier mobility are being developed.Two typical materials are transition metal dichalcogenides(TMDs)and black phosphorus,which exhibit layered structure,layer-dependent band structure and strong quantum con-straints[3−5].As a congener of phosphorus,arsenic can complement the bandgap of existed 2D materials[6−18].

Gapless indica rice genome reveals synergistic contributions of active transposable elements and segmental duplications to rice genome evolution

The ultimate goal of genome assembly is a high-accuracy gapless genome.Here,we report a new assembly pipeline that is used to produce a gapless genome for the indica rice cultivar Minghui 63.The resulting 397.71-Mb final assembly is composed of 12 contigs with a contig N50 size of 31.93 Mb.Each chromosome is represented by a single contig and the genomic sequences of all chromosomes are gapless.Quality evaluation of this gapless genome assembly showed that gene regions in our assembly have the highest completeness compared with the other 15 reported high-quality rice genomes.Further comparison with the japonica rice genome revealed that the gapless indica genome assembly contains more transposable elements(TEs)and segmental duplications(SDs),the latter of which produce many duplicated genes that can affect agronomic traits through dose effect or sub-/neo-functionalization.The insertion of TEs can also affect the expression of duplicated genes,which may drive the evolution of these genes.Furthermore,we found the expansion of nucleotide-binding site with leucine-rich repeat disease-resistance genes and cis-zeatin-O-glucosyltransferase growth-related genes in SDs in the gapless indica genome assembly,suggesting that SDs contribute to the adaptive evolution of rice disease resistance and developmental processes.Collectively,our findings suggest that active TEs and SDs synergistically contribute to rice genome evolution.

Controllable growth and flexible optoelectronic devices of regularly-assembled Bi2S3 semiconductor nanowire bifurcated junctions and crosslinked networks

Regularly assembled structures of nanowires, such as aligned arrays, junctions and interconnected networks, have great potential for the applications in logical circuits, address decoders, photoelectronic devices and transparent electrodes. However, for now it is still lack of effective approaches for constructing nanowire bifurcated junctions and crosslinked networks with ordered orientations and high quality. Herein, we report the controlled growth of Bi2S3 semiconductor nanowire bifurcated junctions and crosslinked networks with well-aligned directions and high crystalline degree by utilizing the proportional lattice match between nanowires and substrates. Taking advantages of the “tip-to-stem splice” assembly of individual nanowires, the precise orientation alignments of Bi2S3 semiconductor nanowire bifurcated junctions and crosslinked networks were successfully realized. The controlled growth mechanism and structural evolution process have been elucidated by detailed atomic structure characterizations and modeling. The highly crystal quality and direct energy bandgap of as-assembled photodetectors based on individual bismuth sulfide nanowires enabled high photoresponsivity and fast switch time under light illumination. The three-terminal devices based on nanowire bifurcated junctions present rapid carrier transport across the junction. The flexible photodetectors based on nanowire crosslinked networks show very minimal decay of photocurrent after long-term bending test. This work may provide new insights for the guided construction and regular assembly of low-dimensional ordered functional nanostructures towards advanced nanotechnologies.

A novel mesenchymal stem cell-based regimen for acute myeloid leukemia differentiation therapy

Currently the main treatment of acute myeloid leukemia(AML)is chemotherapy combining hematopoietic stem cell transplantation.However,the unbearable side effect of chemotherapy and the high risk of life-threatening infections and disease relapse following hematopoietic stem cell transplantation restrict its application in clinical practice.Thus,there is an urgent need to develop alternative therapeutic tactics with significant efficacy and attenuated adverse effects.Here,we revealed that umbilical cord-derived mesenchymal stem cells(UC-MSC)efficiently induced AML cell differentiation by shuttling the neutrophil elastase(NE)-packaged extracellular vesicles(EVs)into AML cells.Interestingly,the generation and release of NE-packaged EVs could be dramatically increased by vitamin D receptor(VDR)activation in UC-MSC.Chemical activation of VDR by using its agonist 1a,25-dihydroxyvitamin D3 efficiently enhanced the pro-differentiation capacity of UC-MSC and then alleviated malignant burden in AML mouse model.Based on these discoveries,to evade the risk of hypercalcemia,we synthetized and identified sw-22,a novel non-steroidal VDR agonist,which exerted a synergistic prodifferentiation function with UC-MSC on mitigating the progress of AML.Collectively,our findings provided a non-gene editing MSC-based therapeutic regimen to overcome the differentiation blockade in AML.

In Vivo Voltammetric Imaging of Metal Nanoparticle-Catalyzed Single-Cell Electron Transfer by Fermi Level-Responsive Graphene

Metal nanomaterials can facilitate microbial extracellular electron transfer(EET)in the electrochemically active biofilm.However,the role of nanomaterials/bacteria interaction in this process is still unclear.Here,we reported the single-cell voltammetric imaging of Shewanella oneidensis MR-1 at the single-cell level to elucidate the metal-enhanced EET mechanism in vivo by the Fermi level-responsive graphene electrode.Quantified oxidation currents of~20 fA were observed from single native cells and gold nanoparticle(AuNP)-coated cells in linear sweep voltammetry analysis.On the contrary,the oxidation potential was reduced by up to 100 mV after AuNP modification.It revealed the mechanism of AuNP-catalyzed direct EET decreasing the oxidation barrier between the outer membrane cytochromes and the electrode.Our method offered a promising strategy to understand the nanomaterials/bacteria interaction and guide the rational construction of EET-related microbial fuel cells.

High-performance Li-ion capacitor based on black-TiO2-x/graphene aerogel anode and biomass-derived microporous carbon cathode

Lithium-ion capacitor (LIC) has been regarded as a promising energy storage system with high powder density and high energy density.However,the kinetic mismatch between the anode and the cathode is a major issue to be solved.Here we report a high-performance asymmetric LIC based on oxygen-deficient black-TiO2-x/graphene (B-TiO2-x/G) aerogel anode and biomass derived microporous carbon cathode.Through a facile one-pot hydrothermal process,graphene nanosheets and oxygen-vacancy-rich porous B-TiO2-x/G nanosheets were self-assembled into three-dimensional (3D) interconnected B-TiO2-x/G aerogel.Owing to the rich active sites,high conductivity and fast kinetics,the B-TiO2-x/G aerogel exhibits remarkable reversible capacity,high rate capability and long cycle life when used as anode material for lithium ion storage.Moreover,density functional theory (DFT) calculation reveals that the incorporation of graphene nanosheets can reduce the energy barrier of Li^+ diffusion in B-TiO2-x.The asymmetric LIC based on B-TiO2-x/G aerogel anode and naturally-abundant pine-needles derived microporous carbon (MPC) cathode work well within a large voltage window (1.0-4.0 V),and can deliver high energy density (166.4 Wh·kg^-1 at 200 mA·g^-1),and high power density (7.9 kW·kg^-1 at 17.1 Wh·kg^-1).Moreover,the LIC shows a high capacitance retention of 87% after 3,000cycles at 2,000 mA·g^-1.The outstanding electrochemical performances indicate that the rationally-designed LICs have promising prospect to serve as advanced fast-charging energy storage devices.

Recent advances in anode materials for potassium-ion batteries:A review

Potassium-ion batteries(PIBs)are appealing alternatives to conventional lithium-ion batteries(LIBs)because of their wide potential window,fast ionic conductivity in the electrolyte,and reduced cost.However,PIBs suffer from sluggish K+reaction kinetics in electrode materials,large volume expansion of electroactive materials,and the unstable solid electrolyte interphase.Various strategies,especially in terms of electrode design,have been proposed to address these issues.In this review,the recent progress on advanced anode materials of PIBs is systematically discussed,ranging from the design principles,and nanoscale fabrication and engineering to the structure-performance relationship.Finally,the remaining limitations,potential solutions,and possible research directions for the development of PIBs towards practical applications are presented.This review will provide new insights into the lab development and real-world applications of PIBs.

二氧化碳快速剥离Zintl相硅化钙制备超薄Si/SiO_(x)/C纳米片及其高效储锂性能

半导体硅(Si)纳米材料在电子、物理、储能等领域有着广阔的应用前景.然而,到目前为止,由于一些长期存在的难题,如制备工艺复杂,时间、能耗较大等,通过高效低成本的途径实现纳米硅材料的规模化生产依然具有挑战.在本工作中,我们报道了一种绿色、廉价的纳米Si材料的制备方法:通过CO_(2)快速热剥离层状Zintl相化合物CaSi_(2)高产率地制备二维超薄Si/SiO_(x)纳米片.我们发现CaSi_(2)可以在一定条件下和CO_(2)稳定反应.利用此特性并借助温和超声处理,可以高产量制备出超薄Si/SiO_(x)纳米片.通过导电化处理,得到Si/SiO_(x)/C复合纳米片.该复合材料作为锂离子电池的负极材料,具有较高的可逆容量和优异的电化学稳定性.我们希望本研究能为批量生产高容量锂离子电池的硅基纳米结构材料提供新的思路.

2D layered black arsenic-phosphorus materials:Synthesis,properties,and device applications

Phosphorene,especially black phosphorus(BP),has attracted considerable attention due to the unique characteristics,such as tunable direct bandgap,high carrier mobility,and strong in-plane anisotropy.Recently,a new modification strategy for black phosphorus has been developed by alloying black phosphorus with the congener element arsenic.The elemental composition tuning of black phosphorus with arsenic can not only maintain its special crystal structure and high anisotropy but also modify its electrical and optical properties for the further applications of multifunctional devices.The achieved two-dimensional(2D)black arsenic-phosphorus materials exhibit outstanding optical,electrical,and photoelectric properties,such as very narrow band gap,anisotropic infrared absorption,and bipolar transfer characteristics,presenting great potential in infrared photodetectors and highperformance field effect transistors(FETs).In this review,we introduce the recent progress made in the synthesis and applications of black arsenic-phosphorus,and provide an outlook and perspectives on the current challenges and future opportunities in this field.We hope that this review can bring new insights and inspirations on the further development of 2D black arsenic-phosphorus based materials and devices.

Strong and Injectable Hydrogels Based on Multivalent Metal Ion-Peptide Cross-linking

Injectable hydrogels are ideal biomaterials tor delivering cells,growth tactors and dmgs specifically to localized lesions and subsequent controlled release.Many factors can a fleet the efficacy of injectable hydrogels.To avoid potential damage to encapsulated cells or dmgs,injectable hydrogels should be highly dynamic so that they can undergo shear-thinning at low strain rates and rapidly refonn after injection.However,dynamic hydrogels are often mechanically weak,leading to the leakage of encapsulated cells or drugs.Here we demonstrated a convenient method to improve the mechanical strength without jeopardizing the dynamic properties of hydrogels by using metal ion-peptide crosslinkers containing multiple metal ion-ligand bonds.We showed that the dynamic properties of the hydrogels correlated with the intrinsic dynamics of the metal-ligand bonds and were not atlected by the fonnation of multivalent binding.Yet,the mechanical stability of the hydrogels was significantly improved due to the increased themiodynamic stability of the crosslinkers.We turthcr showed that the drug release rates were slowed down by the formation of multivalent crosslinkers.Our results highlight the importance of ligand valency to themechanical response of hydrogels and provide a universal route to rationally tune the dynamic and mechanical properties of injectable hydrogels.

Crosstalk between IL-15Rα^(+)tumor-associated macrophages and breast cancer cells reduces CD8+T cell recruitment

Background:Interleukin-15(IL-15)is a promising immunotherapeutic agent owing to its powerful immune-activating effects.However,the clinical benefits of these treatments are limited.Crosstalk between tumor cells and immune cells plays an important role in immune escape and immunotherapy drug resistance.Herein,this study aimed to obtain in-depth understanding of crosstalk in the tumor microenvironment for providing potential therapeutic strategies to prevent tumor progression.Methods:T-cell killing assays and co-culture models were developed to determine the role of crosstalk between macrophages and tumor cells in breast cancer resistant to IL-15.Western blotting,histological analysis,CRISPR-Cas9 knockout,multi-parameter flow cytometry,and tumor cell-macrophage co-injection mouse models were developed to examine the mechanism by which IL-15Rα^(+)tumor-associated macrophages(TAMs)regulate breast cancer cell resistance to IL-15.Results:We found thatmacrophages contributed to the resistance of tumor cells to IL-15,and tumor cells induced macrophages to express high levels of theαsubunit of the IL-15 receptor(IL-15Rα).Further investigation showed that IL-15Rα^(+)TAMs reduced the protein levels of chemokine CX3C chemokine ligand 1(CX3CL1)in tumor cells to inhibit the recruitment of CD8^(+)T cells by releasing the IL-15/IL-15Rαcomplex(IL-15Rc).Administration of an IL-15Rc blocking peptide markedly suppressed breast tumor growth and overcame the resistance of cancer cells to anti-programmed cell death protein 1(PD-1)antibody immunotherapy.Interestingly,Granulocyte-macrophage colony-stimulating factor(GMCSF)inducedγchain(γc)expression to promote tumor cell-macrophage crosstalk,which facilitated tumor resistance to IL-15.Additionally,we observed that the non-transcriptional regulatory function of hypoxia inducible factor-1alpha(HIF-1α)was essential for IL-15Rc to regulateCX3CL1 expression in tumor cells.Conclusions:The IL-15Rc-HIF-1α-CX3CL1 signaling pathway serves as a crosstalk between macrophages and tumor cells in the tumormicroenvironment of breast cancer.Targeting this pathway may provide a potential therapeutic strategy for enhancing the efficacy of cancer immunotherapy.