Cellulose nanofibril separator from Coffea arabica waste for supercapacitor applications

Biomass derived cellulose-based separators has gained popularity in the field of supercapacitors as they are highly capable of preventing short circuiting due to their increased mesoporous nature and these membranes are found to perform well with excellent electrochemical properties. In our research work, we have adopted the 2,2,6,6–tetramethylpiperidine–1–oxyl (TEMPO)-mediated oxidation and developed an innovative cellulose membrane by employing coffee pulp as raw material. The prepared biopolymer separator explicitly showed a necessary porosity of 55% with uniformly distributed pores which facilitates the movement of ions easily without any obstruction. It also showed a high thermal stability at low thermal degradation temperature of 321 ℃ and an increased uptake of electrolyte about 266% with a voluminous value of 3 mS cm−1 for ionic conductivity. These separators are found to be environmentally friendly and they could be processed at minimal cost. When comparing our separators with the commercially available separators our cellulose separators are found to perform well and this is proved through the obtained results and we suggest that it could be an excellent alternative to celgard separator in the field of supercapacitor applications.