Sn0.1-Li4Ti5O12/C as a promising cathode material with a large capacity and high rate performance for Mg-Li hybrid batteries.

The development prospects of conventional Li-ion batteries are limited by the paucity of Li resources. Mg-Li hybrid batteries (MLIBs) combine the advantages of Li-ion batteries and magnesium batteries. Li+ can migrate rapidly in the cathode materials, and the Mg anode has the advantage of being dendrite-free. In this study, a type of Li4Ti5O12 composite material doped with Sn4+ and a conductive carbon skeleton (Li4Ti4.9Sn0.1O12/C, Sn0.1-LTO/C) was prepared by a simple one-pot sol-gel method. The doped Sn4+ replaces part of Ti4+ in the crystal lattice, which makes Ti3+ require charge compensation, thus improving the ionic conductivity. The intervention of the conductive carbon skeleton further improves the conductivity of the Sn0.1-LTO/C composite material. The performance of Sn0.1-LTO/C as the cathode of MLIBs is explored. The initial discharge capacity was 159.1 mA h g-1 at 0.5 C, and it was maintained at 105 mA h g-1 even after 500 cycles. The excellent electrochemical performance is attributed to a small amount of Sn doping and the involvement of the conductive carbon skeleton, which indicated that the Sn0.1-LTO/C composite material provides great potential application in MLIBs.

Biomimetic Hierarchically Silver Nanowire Interwoven MXene Mesh for Flexible Transparent Electrodes and Invisible Camouflage Electronics.

Flexible transparent electrodes demand high transparency, low sheet resistance, as well as excellent mechanical flexibility simultaneously, however they still remain to be a great challenge due to"trade-off" effect. Herein, inspired by a hollow interconnected leaf vein, we developed robust transparent conductive mesh with biomimetic interwoven structure via hierarchically self-assembles silver nanowires interwoven metal carbide/nitride (MXene) sheets along directional microfibers. Strong interfacial interactions between plant fibers and conductive units facilitate hierarchically interwoven conductive mesh constructed orderly on flexible and lightweight veins while maintaining high transparency, effectively avoiding the trade-off effect between optoelectronic properties. The flexible transparent electrodes exhibit sheet resistance of 0.5 Ω sq-1 and transparency of 81.6%, with a remarkably high figure of merit of 3523. In addition, invisible camouflage sensors are further successfully developed as a proof of concept that could monitor human body motion signals in an imperceptible state. The flexible transparent conductive mesh holds great potential in high-performance wearable optoelectronics and camouflage electronics.

Smart Textile Based on 3D Stretchable Silver Nanowires/MXene Conductive Networks for Personal Healthcare and Thermal Management.

Wearable electronics have enriched daily lives by providing smart functions as well as monitoring body health conditions. However, the realization of wearable electronics with personal healthcare and thermal comfort management of the human body is still a great challenge. Furthermore, manufacturing such on-skin wearable electronics on traditional thin-film substrates results in limited gas permeability and inflammation. Herein, we proposed a personal healthcare and thermal management smart textile with a three-dimensional (3D) interconnected conductive network, formed by silver nanowires (AgNWs) bridging lamellar structured transition-metal carbide/carbonitride (MXene) nanosheets deposited on nonwoven fabrics. Benefiting from the interconnected conductive network synergistic effect of one-dimensional (1D) AgNWs bridging two-dimensional (2D) MXene, the strain sensor exhibits excellent durability (>1500 stretching cycles) and high sensitivity (gauge factor (GF) = 1085) with a wide strain range limit (∼100%), and the details of human body activities can be accurately recognized and monitored. Moreover, thanks to the excellent Joule heating and photothermal effect endowed by AgNWs and MXene, the multifunctional smart textile with direct temperature visualization and solar-powered temperature regulation functions was successfully developed, after further combination of thermochromic and phase-change functional layers, respectively. The smart textiles with a stretchable AgNW-MXene 3D conductive network hold great promise for next-generation personal healthcare and thermal management wearable systems.