Stable and dendrite-free lithium metal anodes enabled by carbon paper incorporated with ultrafine lithiophilic TiO2 derived from MXene and carbon dioxide

Lithium (Li) metal anode is deemed as one of the most fascinating anodes due to its high energy density. Nonetheless, low Coulombic efficiency and safety issues caused by detrimental Li dendrites growth severely hamper its practical application. Herein, we construct an ultrafine TiO2 confined in 3D freestanding carbon paper by one-step green in-situ oxidation of Ti3C2Tx MXene film with greenhouse gas CO2. The lithiophilic TiO2 seeds and freestanding 3D carbon matrix can synergistically induce uniform Li deposition and buffer the volume changes during lithium striping and deposition, which ensure improved electrochemical performance with high Coulombic efficiency and low overpotential, etc. The growth process of metallic Li on C/TiO2 is also systematically investigated. Moreover, the C/TiO2@Li parallel to LiFePO4 full batteries present a stable cycling performance over 250cycles at 1.0C and superior rate performance. Additionally, this work proposes an alternative way to utilize CO2, which may alleviate greenhouse effect and boost sustainable development. These results may be useful for both the design of dendrite-free lithium metal batteries and the sustainable utilizing of CO2.

Automated summary

By constructing nanoscale TiO2 in 3D carbon paper and investigating its interaction with lithium, the cycling stability and charge-discharge efficiency of lithium metal batteries can be effectively improved. Utilizing CO2 as a green material, an alternative way to utilize CO2 resources is proposed for sustainable development.