Hai Benrong, Liu Changsheng
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China.
Materials (Basel). 2022 Apr 11;15(8):2787. doi: 10.3390/ma15082787.
Bismuth oxide (Bi2O3) is an auspicious anode material for sodium-ion batteries owing to its high theoretical capacity and abundant Bi resources. However, the poor electronic conductivity and huge volume expansion of Bi2O3 during cycling lead to the low coulombic efficiency and unstable cycling stability. Aiming to suppress these issues, we use highly conductive reduced graphene oxide (rGO) as a continuous skeleton to fabricate a Bi2O3@rGO heterostructure. It exhibits high reversibility and stability for electrochemical sodium storage by delivering a reversible capacity of 161 mAh g−1 after 100 cycles at 50 mA g−1, which completely outperforms Bi2O3 (43 mAh g−1). In addition, the coulombic efficiency of the heterostructure stabilizes at >90% upon only 3 cycles. The results can be attributed to the dual function of rGO in supporting Bi2O3 nanoparticles and providing conductive pathways to fasten electron transport.
氧化铋（Bi2O3）因其高理论容量和丰富的铋资源，是一种适用于钠离子电池的阳极材料。然而，Bi2O3在循环过程中电子导电性差且体积膨胀巨大，导致库仑效率低和循环稳定性不稳定。为了抑制这些问题，我们使用高导电性的还原氧化石墨烯（rGO）作为连续骨架来制备Bi2O3@rGO异质结构。它在50 mA g−1下循环100次后，通过提供161 mAh g−1的可逆容量，表现出高可逆性和电化学储钠稳定性，这完全优于Bi2O3（43 mAh g−1）。此外，该异质结构仅经过3次循环，库仑效率就稳定在>90%。这些结果可归因于rGO在支撑Bi2O3纳米颗粒和提供导电通路以加速电子传输方面的双重作用。
