A Calcium Organic Salt/rGO composite with Low Solubility and High Conductivity as a Sustainable Anode for Sodium-Ion Batteries

Graphical Two in one : A composite of a calcium organic salt, Cabpdc (bpdc=4,4′-biphenyldicarboxylate) and reduced graphene oxide (rGO) improves two issues related to organic electrodes: high solubility in organic electrolytes and low electronic conductivity. The Cabpdc/rGO composite displays competitive cycle and rate performances as an anode for sodium-ion batteries. Organic electrodes hold great promise for sustainable electrodes in sodium-ion batteries (SIBs) owing to their easy availability from biomass. However, traditional organic electrodes suffer from two inherent problems, high solubility in organic electrolytes and low electronic conductivity. Here, a calcium organic salt, Cabpdc (bpdc=4,4′-biphenyldicarboxylate) was designed and formed into a composite with reduced graphene oxide (rGO) to improve these two problems by a “two-in-one” approach. As expected, the Cabpdc/rGO composite displayed competitive cycle and rate performances as an anode for SIBs. Additionally, all-organic sodium-ion full cells were successfully fabricated combining this anode with a commercial organic cathode, promising applications for sustainable SIBs.