Chemical interaction motivated structure design of layered metal carbonate hydroxide/MXene composites for fast and durable lithium ion storage

Rational architecture design has turned out to be an effective strategy in improving the electrochemical performance of electrode materials for batteries.However,an elaborate structure that could simultaneously endow active materials with promoted reaction reversibility,accelerated kinetic and restricted volume change still remains a huge challenge.Herein,a novel chemical interaction motivated structure design strategy has been proposed,and a chemically bonded Co(CO_(3))_(0.5)OH·0.11 H_(2)O@MXene(CoCH@MXene)layered-composite was fabricated for the first time.In such a composite,the chemical interaction between Co^(2+)and MXene drives the growth of smaller-sized CoCH crystals and the subsequent formation of interwoven CoCH wires sandwiched in-between MXene nanosheets.This unique layered structure not only encourages charge transfer for faster reaction dynamics,but buffers the volume change of CoCH during lithiation-delithiation process,owing to the confined crystal growth between conductive MXene layers with the help of chemical bonding.Besides,the sandwiched interwoven CoCH wires also prevent the stacking of MXene layers,further conducive to the electrochemical performance of the composite.As a result,the as-prepared CoCH@MXene anode demonstrates a high reversible capacity(903.1 mAh g^(-1)at 100 mA g^(-1))and excellent cycling stability(maintains 733.6 mAh g^(-1)at1000 mA g^(-1)after 500 cycles)for lithium ion batteries.This work highlights a novel concept of layerby-layer chemical interaction motivated architecture design for futuristic high performance electrode materials in energy storage systems.

Layered coordination polymer with two-dimensional covalent bismuth-organic networks:Semiconductor and lithium ion storage

Single crystals of a bismuth-based coordination polymer(CP)with carboxyl-thiol ligands,[Bi(C_(8)H_(2)O_(4)S_(2))(C2H8N)]n(Bi-DSBDC-DMA,DMBDC=2,5-disulfur-1,4-dicarboxylate,DMA=dimethylamine),have been successfully synthesized.X-ray diffraction analysis reveals that Bi-DSBDC-DMA possesses a layered structure,with two-dimensional(2D)Bi-DSBDC networks alternating with layers composed of dimethylamine ions.This material demonstrates semiconducting properties,featuring an optical bandgap of 2.2 eV and an electrical conductivity of 2×10^(-8) S/cm.Furthermore,electrodes based on this material exhibit a capacity of 250 mAh/g after 200 cycles for lithium-ion storage.

Post lithium ion batteries for emerging energy storage technologies

It is obvious that in the next ten years,lithium ion batteries are still the dominating power source for a wide range of products including consumable electronics,vehicles(cars,motorbikes,scooters,buses),drones,and even robots and tanks.However,in the pursuit of cost-effective,safety-reliable,and highly efficient energy storage technologies,researchers are developing

Highly dispersed Co-Mo sulfide nanoparticles on reduced graphene oxide for lithium and sodium ion storage

A novel hybrid,highly dispersed spinel Co-Mo sulfide nanoparticles on reduced graphene oxide(Co3S4/CoMo2S4@rGO),is reported as anode for lithium and sodium ion storage.The hybrid is synthesized by one-step hydrothermal method but exhibits excellent lithium and sodium storage performances.The as-synthesized Co3S4/CoMo2S4@rGO presents reversible capacity of 595.4 mA·h·g^−1 and 408.8 mA·h·g^−1 after 100 cycles at a current density of 0.2 A·g^−1 for lithium and sodium ion storages,respectively.Such superior performances are attributed to the unique composition and structure of Co3S4/CoMo2S4@rGO.The rGO provides a good electronically conductive network and ensures the formation of spinel Co3S4/CoMo2S4 nanoparticles,the Co3S4/CoMo2S4 nanoparticles provide large reaction surface for lithium and sodium intercalation/deintercalation,and the spinel structure allows fast lithium and sodium ion diffusion in three dimensions.

Ultrathin nanobelts-assembled Chinese knot-like 3D TiO2 for fast and stable lithium storage

Nanostructured TiO2 has applications in solar cells, photocatalysts, and fast- charging, safe lithium ion batteries （LIBs）. To meet the demand of high-capacity and high-rate LIBs with TiO2-based anodes, it is important to fine-tune the nanoarchitecture using a well-controlled synthesis approach. Herein, we report a new approach that involves epitaxial growth combined with topotactic conversion to synthesize a unique type of three-dimensional （3D） TiO2 nano- architecture that is assembled by well-oriented ultrathin nanobelts. The whole nanoarchitecture displays a 3D Chinese knot-like morphology; the core consists of robust perpendicular interwoven nanobelts and the shell is made of extended nanobelts. The nanobelts oriented in three perpendicular [001]A directions facilitate Li＋ penetration and diffusion. Abundant anatase/TiO2-B interfaces provide a large amount of interfacial pseudocapacitance. A high and stable capacity of 130 mA.h.g-1 was obtained after 3,000 cycles at 10 A·g-1 （50 C）, and the high-rate property of our material was greater than that of many recently reported high-rate TiO2 anodes. Our result provides, not only a novel synthesis strategy, but also a new type of 3D anatase TiO2 anode that may be useful in developing long-lasting and fast-charging batteries.