Phase engineering of MoS$_2$ monolayers: A pathway to enhanced lithium-polysulfide battery performance

TL;DR

This paper investigates how phase engineering of MoS$_2$ monolayers, specifically switching between 2H and 1T$^\prime$ phases, can improve lithium-sulfur battery performance by enhancing interactions, catalytic activity, and stability.

Contribution

It demonstrates that the metallic 1T$^\prime$ phase of MoS$_2$ provides superior electrochemical properties for Li--S batteries, and introduces a tunable phase transition for optimized performance.

Findings

1T$^\prime$-MoS$_2$ shows stronger Li--S interactions.

Enhanced catalytic activity suppresses polysulfide dissolution.

Reversible phase transition enables balanced conductivity and stability.

Abstract

This study explores the potential of MoS$_2$ polymorphs, specifically the semiconducting 2H phase and the metallic 1T$^\prime$ phase, as anchoring materials to enhance the electrochemical performance of lithium-sulfur (Li--S) batteries. Using density functional theory calculations, we show that 1T$^\prime$-MoS$_2$ exhibits stronger Li--S interactions, greater charge transfer, and enhanced catalytic activity compared to its 2H counterpart, effectively suppressing polysulfide dissolution and facilitating redox reactions. The reversible 2H$\leftrightarrow$1T$^\prime$ transition offers a tunable design space for balancing conductivity and structural stability. These findings position hybrid MoS$_2$ architectures as promising platforms for next-generation Li--S batteries with improved energy density, cycling stability, and rate capability.