Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy...Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy-rich TiO_(2)(Vo-TiO_(2))nanoparticles(NPs)uniformly dispersing on Ti_(3)C_(2)T_(x)(Vo-TiO_(2)/Ti_(3)C_(2) T_(x))with excellent lithiophilicity feature are presented as effective composite anodes,on which a dense and uniform Li growth behavior is observed.Based on electrochemical studies,mutiphysics simulation and theoretical calculation,it is found that Vo-TiO_(2) coupling with three dimensional(3 D)conductive Ti_(3)C_(2) T_(x) MXene forms highly ordered lithiophilic sites which succeed in guiding Li ions flux and adsorption,thus modulating the uniform Li nucleation and growth.As a result,this composite electrode is capable of preserving Li with high areal capacity of~10 mAh cm^(-2) without the presence of dendrites and large volume expansion.Consequently,the as-prepared Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anode shows outstanding performance including low voltage hysteresis(~19 mV)and superior durability(over 750 h).When assembling with the Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anodes,lithium-oxygen batteries also deliver enhanced cycling stability and improved rate performance.This work demonstrates the effectiveness of oxygen vacancies in guiding Li nucleating and plating behavior at initial stage and brings a promising strategy for promoting the development of advanced Li metal-based batteries.展开更多
Metallic lithium is deemed as the“Holy Grail”anode in high-energy-density secondary batteries.Uncontrollable lithium dendrite growth and related issues originated from uneven concentration distribution of Li+in the ...Metallic lithium is deemed as the“Holy Grail”anode in high-energy-density secondary batteries.Uncontrollable lithium dendrite growth and related issues originated from uneven concentration distribution of Li+in the vicinity of the anode,however,induce severe safety concerns and poor cycling efficiency,dragging lithium metal anode out of practical application.Herein we address these issues by using cross-linked lithiophilic amino phosphonic acid resin as the effective host with the ion-transportenhancement feature.Based on theoretical calculations and multiphysics simulation,it is found that this ion-transportenhancement feature is capable of facilitating the self-concentration kinetics of Li+and accelerating Li^(+)transfer at the electrolyte/electrode interface,leading to uniform bulk lithium deposition.Experimental results show that the proposed lithiumhosting resin decreases the irreversible lithium capacity and improves lithium utilization(with the Coulombic efficiency(CE)of 98.8%over 130 cycles).Our work demonstrates that inducing the self-concentrating distribution of Li+at the interface can be an effective strategy for improving the interfacial ion concentration gradient and optimizing lithium deposition,which opens a new avenue for the practical development of next-generation lithium metal batteries.展开更多
Circular RNAs (circRNAs) constitute a novel class of endogenous noncoding RNAs characterized by a covalently closed structure and involved in multiple biological processes. The main biological functions and properties...Circular RNAs (circRNAs) constitute a novel class of endogenous noncoding RNAs characterized by a covalently closed structure and involved in multiple biological processes. The main biological functions and properties of circRNAs can be defined by five features: a "sponging" effect on other RNA species, post-transcriptional regulation, rolling circle translation, generation of pseudogenes, and splicing interference. Although circRNAs were first detected decades ago, the role of circRNAs and the mechanisms underlying their actions remain incompletely characterized. Recently, circRNAs were reported to play indispensable roles in regulating metabolic and signal transduction events controlling the proliferation, migration, and survival of cells. Importantly, many studies demonstrated that dysregulated circRNA expression is associated with the development of multiple diseases, including cancer. In this review, we summarize current knowledge on the roles and mechanisms of circRNAs in cancer and discuss their functions as oncogenes or tumor suppressors in different tumor types.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.21905033)the Science and Technology Department of Sichuan Province(Grant No.2019YJ0503)the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization(2020P4FZG02A)。
文摘Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy-rich TiO_(2)(Vo-TiO_(2))nanoparticles(NPs)uniformly dispersing on Ti_(3)C_(2)T_(x)(Vo-TiO_(2)/Ti_(3)C_(2) T_(x))with excellent lithiophilicity feature are presented as effective composite anodes,on which a dense and uniform Li growth behavior is observed.Based on electrochemical studies,mutiphysics simulation and theoretical calculation,it is found that Vo-TiO_(2) coupling with three dimensional(3 D)conductive Ti_(3)C_(2) T_(x) MXene forms highly ordered lithiophilic sites which succeed in guiding Li ions flux and adsorption,thus modulating the uniform Li nucleation and growth.As a result,this composite electrode is capable of preserving Li with high areal capacity of~10 mAh cm^(-2) without the presence of dendrites and large volume expansion.Consequently,the as-prepared Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anode shows outstanding performance including low voltage hysteresis(~19 mV)and superior durability(over 750 h).When assembling with the Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anodes,lithium-oxygen batteries also deliver enhanced cycling stability and improved rate performance.This work demonstrates the effectiveness of oxygen vacancies in guiding Li nucleating and plating behavior at initial stage and brings a promising strategy for promoting the development of advanced Li metal-based batteries.
基金This work was financially supported by the National Natural Science Foundation of China(No.21905033)the Science and Technology Department of Sichuan Province(No.2019YJ0503)The support from the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization(No.2020P4FZG02A)is also appreciated.
文摘Metallic lithium is deemed as the“Holy Grail”anode in high-energy-density secondary batteries.Uncontrollable lithium dendrite growth and related issues originated from uneven concentration distribution of Li+in the vicinity of the anode,however,induce severe safety concerns and poor cycling efficiency,dragging lithium metal anode out of practical application.Herein we address these issues by using cross-linked lithiophilic amino phosphonic acid resin as the effective host with the ion-transportenhancement feature.Based on theoretical calculations and multiphysics simulation,it is found that this ion-transportenhancement feature is capable of facilitating the self-concentration kinetics of Li+and accelerating Li^(+)transfer at the electrolyte/electrode interface,leading to uniform bulk lithium deposition.Experimental results show that the proposed lithiumhosting resin decreases the irreversible lithium capacity and improves lithium utilization(with the Coulombic efficiency(CE)of 98.8%over 130 cycles).Our work demonstrates that inducing the self-concentrating distribution of Li+at the interface can be an effective strategy for improving the interfacial ion concentration gradient and optimizing lithium deposition,which opens a new avenue for the practical development of next-generation lithium metal batteries.
基金supported by the National Natural Science Foundation of China(21905033)the Science and Technology Department of Sichuan Province(2019YJ0503)the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization(2020P4FZG02A)。
文摘构造阳离子空位被认为是一种可以提高电催化剂活性的有效策略.然而,在材料表面高效地引入阳离子空位仍面临诸多挑战.另外,关于阳离子空位对锂-氧气(Li-O_(2))电池氧电极反应活性的影响少有报道.本文报道了在V_(2)C MXene表面原位构造富含钒空位的五氧化二钒(V_(2-x)O_(5)@V_(2)C MXene)的方法,并系统研究了该材料对Li-O_(2)电池氧电极反应的双功能催化活性.结果表明,基于V_(2-x)O_(5)@V_(2)C MXene的Li-O_(2)电池具有良好的性能.其在100 mA g^(-1)电流密度下展示出高的能量效率(83.4%)和优异的循环性能(超过500次循环).密度泛函理论计算结果表明,阳离子钒空位的存在可以提供大量活性位点以降低Li-O_(2)电池氧电极反应能垒并促进反应物的吸附.本工作表明,通过构造阳离子金属空位来调节材料表面电子结构是提高过渡金属氧化物电催化活性的有效路径.
基金This work was supported by the National Natural Science Foundation of China(No.82072723)Natural Science Foundation of Chongqing(No.cstc2020jcyj-msxmX0707)Science and Health Research Project of Chongqing(No.2021MSXM344).
文摘Circular RNAs (circRNAs) constitute a novel class of endogenous noncoding RNAs characterized by a covalently closed structure and involved in multiple biological processes. The main biological functions and properties of circRNAs can be defined by five features: a "sponging" effect on other RNA species, post-transcriptional regulation, rolling circle translation, generation of pseudogenes, and splicing interference. Although circRNAs were first detected decades ago, the role of circRNAs and the mechanisms underlying their actions remain incompletely characterized. Recently, circRNAs were reported to play indispensable roles in regulating metabolic and signal transduction events controlling the proliferation, migration, and survival of cells. Importantly, many studies demonstrated that dysregulated circRNA expression is associated with the development of multiple diseases, including cancer. In this review, we summarize current knowledge on the roles and mechanisms of circRNAs in cancer and discuss their functions as oncogenes or tumor suppressors in different tumor types.
