• Bi 2 MoO 6 has been grown on a preformed Bi 2 O 3 particle to form p-n heterojunction. • The construction of p–n heterojunction improves charge transfer and electrochemical activity. • The BBM10 reveals a larger specific capacitance and improved rate capability. • The photocatalytic performance also significantly enhanced. Heterostructured materials composed of distinct semiconductors can generate built-in electric fields and provide additional active sites, thereby enhancing electron/ion transport and redox reactions for energy storage and photocatalytic applications. In this study, a novel strategy is proposed involving the growth of Bi 2 MoO 6 on preformed Bi 2 O 3 particles to construct a p–n Bi 2 O 3 /Bi 2 MoO 6 heterojunction. The established internal electrostatic field (EIEF) between p-type Bi 2 O 3 and n-type Bi 2 MoO 6 , in conjunction with oxygen vacancy-induced defects, facilitates charge transfer and enhances electrochemical activity. As a result, the energy-related applications of Bi 2 O 3 /Bi 2 MoO 6 , both as a supercapacitor and anode electrode, outperform those of pristine Bi 2 O 3 . The asymmetric supercapacitor (AS) based on Bi 2 O 3 /Bi 2 MoO 6 and activated carbon (AC) exhibits superior electrochemical performance, with an energy density of 31.0 Wh/kg and outstanding cycling durability, retaining 92.7% of its initial capacity after 10,000 cycles. The Bi 2 O 3 /Bi 2 MoO 6 heterojunction also demonstrates an increased photodegradation rate constant toward methylene blue (MB) under illumination with visible light, primarily due to its great charge transfer property
Lee et al. (Wed,) studied this question.