Poor cycling stability in lithium–sulfur(Li–S)batteries necessitates advanced electrode/electrolyte design and innovative interlayer architectures.Heterogeneous catalysis has emerged as a promising approach,leveragi...Poor cycling stability in lithium–sulfur(Li–S)batteries necessitates advanced electrode/electrolyte design and innovative interlayer architectures.Heterogeneous catalysis has emerged as a promising approach,leveraging the adsorption and catalytic performance on lithium polysulfides(LiPSs)to inhibit LiPSs shuttling and improve redox kinetics.In this study,we report an ultrathin and laminar SnO_(2)@MXene heterostructure interlayer(SnO_(2)@MX),where SnO_(2) quantum dots(QDs)are uniformly distributed across the MXene layer.The combined structure of SnO_(2) QDs and MXene,along with the creation of numerous active boundary sites with coordination electron environments,plays a critical role in manipulating the catalytic kinetics of sulfur species.The Li–S cell with the SnO_(2)@MX-modified separator not only demonstrates superior electrochemical performance compared to cells with a bare separator but also induces homogeneous Li deposition during cycling.As a result,an areal capacity of 7.6 mAh cm^(-2) under a sulfur loading of 7.5 mg cm^(-2) and a high stability over 500 cycles are achieved.Our work demonstrates a feasible strategy of utilizing a laminar separator interlayer for advanced Li–S batteries awaiting commercialization and may shed light on the understanding of heterostructure catalysis with enhanced reaction kinetics.展开更多
Hydrodynamic cavitation is one of the major phase change phenomena and occurs with a sudden decrease in the local static pressure within a fluid.With the emergence of microelectromechanical systems(MEMS),high-speed mi...Hydrodynamic cavitation is one of the major phase change phenomena and occurs with a sudden decrease in the local static pressure within a fluid.With the emergence of microelectromechanical systems(MEMS),high-speed microfluidic devices have attracted considerable attention and been implemented in many fields,including cavitation applications.In this study,a new generation of‘cavitation-on-a-chip’devices with eight parallel structured microchannels is proposed.This new device is designed with the motivation of decreasing the upstream pressure(input energy)required for facile hydrodynamic cavitation inception.Water and a poly(vinyl alcohol)(PVA)microbubble(MB)suspension are used as the working fluids.The results show that the cavitation inception upstream pressure can be reduced with the proposed device in comparison with previous studies with a single flow restrictive element.Furthermore,using PVA MBs further results in a reduction in the upstream pressure required for cavitation inception.In this new device,different cavitating flow patterns with various intensities can be observed at a constant cavitation number and fixed upstream pressure within the same device.Moreover,cavitating flows intensify faster in the proposed device for both water and the water–PVA MB suspension in comparison to previous studies.Due to these features,this next-generation‘cavitation-on-a-chip’device has a high potential for implementation in applications involving microfluidic/organ-on-a-chip devices,such as integrated drug release and tissue engineering.展开更多
基金financial support from the Swiss National Science Foundation via the Southeast Asia–Europe Joint Funding Scheme 2020(Grant No.IZJFZ2_202476)funding from the National Natural Science Foundation of China(Grant Nos.22209118 and 00301054A1073)the Fundamental Research Funds for the Central Universities(Grant Nos.1082204112A26,20826044D3083,and 20822041G4080)。
文摘Poor cycling stability in lithium–sulfur(Li–S)batteries necessitates advanced electrode/electrolyte design and innovative interlayer architectures.Heterogeneous catalysis has emerged as a promising approach,leveraging the adsorption and catalytic performance on lithium polysulfides(LiPSs)to inhibit LiPSs shuttling and improve redox kinetics.In this study,we report an ultrathin and laminar SnO_(2)@MXene heterostructure interlayer(SnO_(2)@MX),where SnO_(2) quantum dots(QDs)are uniformly distributed across the MXene layer.The combined structure of SnO_(2) QDs and MXene,along with the creation of numerous active boundary sites with coordination electron environments,plays a critical role in manipulating the catalytic kinetics of sulfur species.The Li–S cell with the SnO_(2)@MX-modified separator not only demonstrates superior electrochemical performance compared to cells with a bare separator but also induces homogeneous Li deposition during cycling.As a result,an areal capacity of 7.6 mAh cm^(-2) under a sulfur loading of 7.5 mg cm^(-2) and a high stability over 500 cycles are achieved.Our work demonstrates a feasible strategy of utilizing a laminar separator interlayer for advanced Li–S batteries awaiting commercialization and may shed light on the understanding of heterostructure catalysis with enhanced reaction kinetics.
基金This work was supported by internal funding of the KTH Energy Platform and TUBITAK(The Scientific and Technological Research Council of Turkey)Support Program for Scientific and Technological Research Project(Grant No.217M869).
文摘Hydrodynamic cavitation is one of the major phase change phenomena and occurs with a sudden decrease in the local static pressure within a fluid.With the emergence of microelectromechanical systems(MEMS),high-speed microfluidic devices have attracted considerable attention and been implemented in many fields,including cavitation applications.In this study,a new generation of‘cavitation-on-a-chip’devices with eight parallel structured microchannels is proposed.This new device is designed with the motivation of decreasing the upstream pressure(input energy)required for facile hydrodynamic cavitation inception.Water and a poly(vinyl alcohol)(PVA)microbubble(MB)suspension are used as the working fluids.The results show that the cavitation inception upstream pressure can be reduced with the proposed device in comparison with previous studies with a single flow restrictive element.Furthermore,using PVA MBs further results in a reduction in the upstream pressure required for cavitation inception.In this new device,different cavitating flow patterns with various intensities can be observed at a constant cavitation number and fixed upstream pressure within the same device.Moreover,cavitating flows intensify faster in the proposed device for both water and the water–PVA MB suspension in comparison to previous studies.Due to these features,this next-generation‘cavitation-on-a-chip’device has a high potential for implementation in applications involving microfluidic/organ-on-a-chip devices,such as integrated drug release and tissue engineering.
