Spontaneously Formed Mott-Schottky Electrocatalyst for Lithium-Sulfur Batteries

Developing effective electrocatalyst and deciphering its mechanism in modulating sulfur-species-conversion is still an important but challenging part for lithium sulfur (Li-S) batteries. Here, a “spontaneous formed” strategy is presented to construct hierarchical CNT@ surface oxidized TiN nanoparticles (CNT@TiON) and the detailed interfaces mediation mechanism of Mott-Schottky effect is disclosed on Li-S chemistries. The results indicate the redistribution of local electron density in TiON is critical to enhancing the sulfur-species utilization, lowering the energy barriers of intermediate step, and facilitating the conversion of PS. As a result, CNT@TiON-S cathodes deliver significantly improved electrochemical performance, including low polarization, fleet reaction kinetics, and lasting cycle stability. This work embraces the local electronic state at heterojunction interface and paves a new way toward the design and understanding of efficient catalysts for Li-S batteries.