Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensio...Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensional(2D)nanomaterials,such as MXene,and show promise for use in energy storage devices.In order to achieve better electrochemical properties of MXene,one crucial technique is to modify its structure by introducing defects or heteroatom dopants,which may expand the interlayer spacing and increase the ion transfer kinetics during the charge/discharge process.Here,a modified two-step multi-element strategy is explored utilizing ammonium citrate as intercalant and nitrogen source to enhance the level of heteroatom doping during annealing of MXene with sulfur.The resulting nitrogen/sulfur co-doped MXene displayed enhanced gravimetric capacitance(495 F g^(-1) at 1 A g^(-1)),outstanding rate capability(180 F g^(-1) at 10 A g^(-1))and excellent cycle stability(98%retention after 6000 charge/discharge cycles).The synthesis of NS-MXene reveals a novel and facile multiheteroatom pathway for functionalizing Ti_(3)C_(2)Tx MXene and demonstrates the potential variety of this family of modified MXenes that has yet to be explored,as well as unveils great promise for use in applications such as high performance supercapacitors.展开更多
The recent progress on the liquid crystalline(LC)dispersion of two-dimensional(2D)transition metal carbides(MXenes)has propelled this unique nanomaterial into a realm of high-performance architectures,such as films an...The recent progress on the liquid crystalline(LC)dispersion of two-dimensional(2D)transition metal carbides(MXenes)has propelled this unique nanomaterial into a realm of high-performance architectures,such as films and fibers.Additionally,compared to architectures made from typical non-LC dispersions,those derived from LC MXene possess tunable ion transport routes and enhanced conductivity and physical properties,demonstrating great potential for a wide range of applications,such as electronic displays,smart glasses,and thermal camouflage devices.This review provides an overview of the progress achieved in the production and processing of LC MXenes,including critical discussions on satisfying the required conditions for LC formation.It also highlights how acquiring LC MXenes has broadened the current solution-based manufacturing paradigm of MXene-based architectures,resulting in unprecedented performances in their conventional applications(e.g.,energy storage and strain sensing)and in their emerging uses(e.g.,tribology).Opportunities for innovation and foreseen challenges are also discussed,offering future research directions on how to further benefit from the exciting potential of LC MXenes with the aim of promoting their widespread use in designing and manufacturing advanced materials and applications.展开更多
基金the Tsinghua-Foshan Innovation Special Fund(Grant No.2019THFS0125)support from Alfred Deakin Postdoctoral Fellowship.Z.Wang acknowledges financial support from China Scholarship Council(File No.201606930013)+2 种基金the Australian Research Council for funding(FT130100380,IH140100018 and DP190103290)the ARC Centre of Excellence for Electromaterials Science(ACES)(No.CE140100012)the Victorian Node of the Australian National Fabrication Facility(ANFF).
文摘Through material innovation,nanoscale structural design and hybrid manufacturing methods,great efforts have been made in developing high-performance energy storage systems.These devices can be comprised of twodimensional(2D)nanomaterials,such as MXene,and show promise for use in energy storage devices.In order to achieve better electrochemical properties of MXene,one crucial technique is to modify its structure by introducing defects or heteroatom dopants,which may expand the interlayer spacing and increase the ion transfer kinetics during the charge/discharge process.Here,a modified two-step multi-element strategy is explored utilizing ammonium citrate as intercalant and nitrogen source to enhance the level of heteroatom doping during annealing of MXene with sulfur.The resulting nitrogen/sulfur co-doped MXene displayed enhanced gravimetric capacitance(495 F g^(-1) at 1 A g^(-1)),outstanding rate capability(180 F g^(-1) at 10 A g^(-1))and excellent cycle stability(98%retention after 6000 charge/discharge cycles).The synthesis of NS-MXene reveals a novel and facile multiheteroatom pathway for functionalizing Ti_(3)C_(2)Tx MXene and demonstrates the potential variety of this family of modified MXenes that has yet to be explored,as well as unveils great promise for use in applications such as high performance supercapacitors.
基金Australian Research Council,Grant/Award Number:IH210100023Australian National Fabrication Facility(ANFF)Victorian node at Deakin University+1 种基金Deakin-CSIRO InSitX X-ray facilityAlfred Deakin Post-doctoral Research Fellowships。
文摘The recent progress on the liquid crystalline(LC)dispersion of two-dimensional(2D)transition metal carbides(MXenes)has propelled this unique nanomaterial into a realm of high-performance architectures,such as films and fibers.Additionally,compared to architectures made from typical non-LC dispersions,those derived from LC MXene possess tunable ion transport routes and enhanced conductivity and physical properties,demonstrating great potential for a wide range of applications,such as electronic displays,smart glasses,and thermal camouflage devices.This review provides an overview of the progress achieved in the production and processing of LC MXenes,including critical discussions on satisfying the required conditions for LC formation.It also highlights how acquiring LC MXenes has broadened the current solution-based manufacturing paradigm of MXene-based architectures,resulting in unprecedented performances in their conventional applications(e.g.,energy storage and strain sensing)and in their emerging uses(e.g.,tribology).Opportunities for innovation and foreseen challenges are also discussed,offering future research directions on how to further benefit from the exciting potential of LC MXenes with the aim of promoting their widespread use in designing and manufacturing advanced materials and applications.