Using eggshell membrane as a separator in supercapacitor

A separator is prepared based on natural and flexible eggshell membrane (ESM) for supercapacitor application. Morphology observation shows that the ESM is consisted of hierarchically ordered macroporous network. With a high decomposition temperature (>220 °C), enough mechanical strength (σmax = 6.59 ± 0.48 MPa, ɛmax = 6.98 ± 0.31%, respectively), and low water uptake and swelling property (<10%), ESM could be a promising candidate for supercapacitor separator. As expected, the supercapacitor with ESM separator exhibits outstanding electrochemical performances, such as low resistance, quick charge–discharge ability (τ is 4.76 s), and good cyclic stability (92% retention after 10,000 cycles). However, the one with PE separator shows worse properties (high resistance, low specific capacitance, etc.). This research provides new insight into the preparation of natural, low-cost and high-performance separator for supercapacitor and other applications.

► An eggshell membrane (ESM) is prepared for the separator in supercapacitor. ► The ESM possesses low swelling, good stability, and high mechanical strength. ► Supercapacitor with the ESM separator exhibits excellent electrochemical performance.