Metal‐Organic Framework/Graphene Nanoplatelet Composite Increases Rate Performance of Lithium–Sulfur Batteries

Abstract

The polysulfide (PS) shuttle mechanism (PSM) is one of the biggest problems of lithium–sulfur (Li–S) batteries, resulting in fast capacity fading and low Coulombic efficiency. Due to electrostatic interactions, polar materials can adsorb the PS intermediates on their surfaces, decreasing the PSM effect. These polar materials should also have high electronic conductivity and surface area to be used in sulfur cathodes of Li–S batteries. In this respect, metal‐organic frameworks (MOF) and their derivatives gain significant attention. In this work, UiO‐66/graphene nanoplatelet (GNP)/sulfur composites are prepared with different UiO‐66/GNP ratios to investigate the effect of MOF amount on the electrochemical performance of Li–S batteries. MOF amount in the composite does not significantly influence performance for moderate S loadings. In contrast, Li–S cells with higher MOF‐loaded cathodes present superior performance at higher sulfur loadings and C rates.