Example：10.1021/acsami.1c06204 or Chem. Rev., 2007, 107, 2411-2502
Sodium borohydride (NaBH4) as a high-capacity material for next-generation sodium-ion capacitors Open Chemistry (IF1.554), Pub Date : 2021-01-01, DOI: 10.1515/chem-2021-0040 Pawel Jeżowski, Olivier Crosnier, Thierry Brousse
Energy storage is an integral part of the modern world. One of the newest and most interesting concepts is the internal hybridization achieved in metal-ion capacitors. In this study, for the first time we used sodium borohydride (NaBH 4 ) as a sacrificial material for the preparation of next-generation sodium-ion capacitors (NICs). NaBH 4 is a material with large irreversible capacity of ca. 700 mA h g −1 at very low extraction potential close to 2.4 vs Na + /Na 0 . An assembled NIC cell with the composite-positive electrode (activated carbon/NaBH 4 ) and hard carbon as the negative one operates in the voltage range from 2.2 to 3.8 V for 5,000 cycles and retains 92% of its initial capacitance. The presented NIC has good efficiency >98% and energy density of ca. 18 W h kg −1 at power 2 kW kg −1 which is more than the energy (7 W h kg −1 at 2 kW kg −1 ) of an electrical double-layer capacitor (EDLC) operating at voltage 2.7 V with the equivalent components as in NIC. Tin phosphide (Sn 4 P 3 ) as a negative electrode allowed the reaching of higher values of the specific energy density 33 W h kg −1 (ca. four times higher than EDLC) at the power density of 2 kW kg −1 , with only 1% of capacity loss upon 5,000 cycles and efficiency >99%.