Investigating role of ammonia in nitrogen-doping and suppressing polyselenide shuttle effect in Na-Se batteries

Sodium-ion battery (SIB) has attracted extensive research attention owing to its high theoretical capacity and low cost. Herein, we synthesize bio-waste-derived activated carbon (BAC) through a facile synthesis process followed by selenium loading (using melt-infusion method) to form BAC@Se composites. The synthesized BAC and its composite BAC@Se revealed excellent rate performance, great cycling stability, and good reversibility. The BAC revealed a maximum specific capacity of 257 mAh/g at 20 mA/g current density. The BAC@Se showed the maximum specific capacity of 701 mAh/g at 50 mA/g current density (equivalent to a specific energy of about 1051 WhKg(-1)/75 WKg(-1)) and good rate performance with 226 mAh/g specific capacity at a high current density of 2500 mA/g. Moreover, the composite revealed good cycling stability by retaining 348 mAh/g capacity at 500 mA/g after 500 cycles. The excellent electrochemical properties were attributed to the unique design of composites, which not only provided the physio-chemically trapped selenium but also ensure the fast kinetics of Na ions through interconnected 3-D channels and high restrain against the dissolution of polyselenides into an electrolyte. This work may shed light on recycling different bio-wastes into energy materials for energy storage devices. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Sodium-ion batteries have attracted significant attention due to their high theoretical capacity and low cost. In this study, bio-waste-derived activated carbon (BAC) was synthesized and selenium was loaded onto it to form BAC@Se composites. The synthesized BAC and BAC@Se composites exhibited excellent rate performance, cycling stability, and reversibility. The unique design of the composites, which provided physio-chemically trapped selenium and fast kinetics for sodium ions, contributed to their exceptional electrochemical properties. This work presents a potential avenue for recycling bio-wastes into energy materials for storage devices.