Abstract：
Bismuth (Bi) exhibits a high theoretical capacity, excellent electrical conductivity properties, and remarkable interlayer spacing, making it an ideal electrode material for supercapacitors. However, during the charge and discharge processes, Bi is prone to volume expansion and pulverization, resulting in a decline in the capacitance. Deposition of a nonmetal on its surface is considered an effective way to modulate its morphology and electronic structure. Herein, we employed the chemical vapor deposition technique to fabricate Se-decorated Bi nanosheets on a nickel foam (NF) substrate. Various characterizations indicated that the deposition of Se on Bi nanosheets regulated their surface morphology and chemical state, while sustaining their pristine phase structure. Electrochemical tests demonstrated that Se-decorated Bi nanosheets exhibited a 51.1% improvement in capacity compared with pristine Bi nanosheets (1313 F/g compared to 869 F/g at a current density of 5 A/g). The energy density of the active material in an assembled asymmetric supercapacitor could reach 151.2 Wh/kg at a power density of 800 W/kg. These findings suggest that Se decoration is a promising strategy to enhance the capacity of the Bi nanosheets.
摘要：
铋（Bi）具有很高的理论容量，优异的导电性能，和显着的层间间距，使其成为超级电容器的理想电极材料。然而,在充电和放电过程中，Bi容易体积膨胀和粉化，导致电容下降。在其表面沉积非金属被认为是调节其形态和电子结构的有效方法。在这里，我们采用化学气相沉积技术在镍泡沫（NF）衬底上制造Se装饰的Bi纳米片。各种表征表明，Se在Bi纳米片上的沉积调节了其表面形态和化学状态，同时维持其原始相结构。电化学测试表明,与原始Bi纳米片相比,Se修饰的Bi纳米片表现出51.1%的容量改善(在5A/g的电流密度下,1313F/g与869F/g相比)。在800W/kg的功率密度下,组装的非对称超级电容器中的活性材料的能量密度可以达到151.2Wh/kg。这些发现表明Se修饰是增强Bi纳米片容量的有前途的策略。
