On the Reversible Sodium Plating/stripping Reaction in Porous SiCN(O) Ceramic: A Feasibility Study

Sodium‐ion batteries (SIBs) are a cost‐effective and sustainable alternative to lithium‐ion batteries (LIBs), which might be independent of rare raw materials. These advantages come at the expense of low energy density. Sodium metal batteries (SMBs) can provide a possible solution. In this work, we present the use of a porous silicon carbonitride (SiCN(O)) ceramic as an anodic matrix for reversible Na‐plating. The role of the pores is investigated and the plating mechanism allowing reversible and uniform plating/stripping of sodium is also presented. Electrochemical studies show a stable and reversible capacity gain of around 60 mAh/g beyond the insertion capacity of the SiCN(O) ceramic over 100 cycles.

Highly porous anodic matrix for Na-plating/stripping: The porosity of SiCN(O) makes this ceramic attractive as a matrix for reversible plating of metallic sodium on the anodic side. The pores serve as an energetically favourable nucleation site reducing the risk of uncontrolled dendrite growth allowing to take advantage of the high gravimetric capacity (1166 mAh/g) of metallic sodium.