Progress and perspectives on electrocatalysis in room-temperature Na–S batteries

Abstract

Room-temperature sodium–sulfur (RT Na–S) batteries that typically feature multielectron conversion chemistries can allow an ultrahigh specific capacity of 1675 mA h g⁻¹ and a high energy density of 1275 W h kg⁻¹ but unfortunately suffer from a lot of intractable challenges from sulfur cathodes. These issues cover the poor electronic conductivity of pristine sulfur and solid products, the severe shuttle effect of polysulfides, and the sluggish redox kinetics, etc. The shuttling behavior of polysulfides always leads to cathode/anode instability and performance degeneration. Recently, the emerging catalysis strategy has been demonstrated as a reliable pathway to tackle the central issues caused by sulfur electrochemistry and revitalize RT Na–S batteries. This review provides an overview of electrocatalysis in the realm of RT Na–S batteries. Sulfur conversion chemistries and critical challenges in RT Na–S batteries are generalized firstly. The emphasis is focused on discussing chemisorption mechanisms for polysulfides, material innovation of catalysts, selectivity and design of catalysts, and a series of catalysis regulation strategies. Finally, existing challenges and perspectives regarding catalysis in RT Na–S batteries are offered, with the aim of propelling its rapid development.