Search

The bacterial cellulose (BC)/Al2O3 nanofibrous composite membrane as a lithium-ion battery separator has been successfully prepared by coating Al2O3 on the BC nanofibers through a simple in situ thermal decomposition of Al(NO3)3 · 9H2O. Thermal treatment tests show that the BC/Al2O3 composite membrane is thermally stable at a high temperature of 200 °C while great shrinkage is observed for the commercial PP-PE-PP membrane. Moreover, the BC/Al2O3 membrane is evaluated to have large porosity and excellent electrolyte uptake, consequently giving rise to larger ionic conductivity, lower interfacial resistance as well as better electrochemical stability. The half lithium-ion battery assembled with the BC/Al2O3 separator demonstrates large discharge capacity and good cycling performance, suggesting that the BC/Al2O3 membrane can be used as a lithium-ion battery separator.

Bacterial cellulose (BC) has attracted much attention due to its low-cost, high specific surface area and ample porosity. In this work, polypyrrole (PPy) and cobalt sulfide (CoS) have been deposited on BC membranes to prepare the nanofibrous composite electrodes of PPy/CoS/BC with excellent flexibility for supercapacitor application. The introduction of CoS remarkably improves the pseudocapacitance and electrochemical stability of PPy/BC-based electrodes. The specific capacitance of the PPy/CoS/BC-based supercapacitors can reach to about 614 F g−1 at a current density of 0.8 mA cm−2 (0.70 A g−1) with maintaining 62.4% of the original value after 300 cycles; while the PPy/BC-based device could retain only 21.7% after 300 cycles. The PPy/CoS/BC-based devices can exhibit an energy density of about 54.5 Wh kg−1 at a power density of 663 W kg−1. This work provides a promising approach to fabricate cost-effective and flexible membranes which can be used as high-performance supercapacitor electrodes.

The increasing trend of portable electronic products requires the development of portable and flexible energy-storage devices, such as flexible supercapacitors. In this study, we deposited polypyrrole (PPy) and nickel sulfide (NiS) on bacterial cellulose (BC) nanofibrous membranes to be used as flexible supercapacitor electrodes. The obtained PPy/NiS/BC composite membranes are highly conductive, with the electrical conductivity up to 5.1 S cm−1. Electrochemical measurements showed that the supercapacitors based on the PPy/NiS/BC electrodes have a high specific capacitance of 713 F g−1 with a power density of 39.5 W kg−1 and an energy density of 239.0 Wh kg−1 at a current density of 0.8 mA cm−2. With increasing current density from 0.2 to 1.6 mA cm−2, the corresponding capacitance changes from 884 to 569 F g−1. The presence of NiS is found to considerably improve the capacitance performance.

Polypyrrole (PPy) and copper sulfide (CuS) have been successfully deposited on bacterial cellulose (BC) membranes to prepare nanofibrous composite electrodes of PPy/CuS/BC for flexible supercapacitor applications. The introduction of CuS remarkably improves the specific capacitance and cycling stability of BC-based electrodes. The specific capacitance of the supercapacitors based on the PPy/CuS/BC electrodes can reach to about 580Fg-1 at a current density of 0.8mAcm-2 and can retain about 73% of their initial value after 300 cycles, while the PPy/BC-based device could retain only 21.7% after 300 cycles. This work provides a promising approach to fabricate cost-effective and flexible nanofibrous composite membranes for high-performance supercapacitor electrodes.