Ning Qiyun,Li Bingwei,Zhou Wang,Xu Xiaoting,Li Jun
In this study, Bi₂O₂Se nanosheets were synthesized via a hydrothermal method, and a Bi₂O₂Se/WSe₂ heterostructure was subsequently constructed using a mechanical compounding approach to develop a photoelectrochemical photodetector. By optimizing the mass ratio and KOH electrolyte concentration, the Bi₂O₂Se/WSe₂ heterostructure exhibited optimal performance at a 7:1 ratio in 0.1 M KOH. Benefiting from the interfacial heterojunction between the two materials, the Bi₂O₂Se/WSe₂ heterostructure achieved a photocurrent density of -2.74 µA/cm² under zero external bias, representing an order-of-magnitude enhancement compared to pristine Bi₂O₂Se nanosheets. Concurrently, the rise time was significantly reduced from 0.86 s to 0.28 s, And the decay time decreased from 4.85 s to 0.32 s, demonstrating superior self-powered characteristics. Furthermore, the Bi₂O₂Se/WSe₂ heterostructure exhibited a maximum photoresponsivity of 61 µA/W. The optimized Bi₂O₂Se/WSe₂ photodetector showed no notable performance degradation during a 10,000 s cyclic on/off illumination test. This work highlights the immense potential of the Bi₂O₂Se/WSe₂ heterostructure-based self-powered photodetector in delivering exceptional self-driven functionality, outstanding optoelectronic properties, and robust stability for practical applications.
The development of advanced electrode materials with high specific capacitance and long-term stability is crucial for next-generation supercapacitors. In this work, a novel Bi₂O₂Se/polyaniline (PANI) composite electrode was synthesized via an optimised synthesis protocol. The developed composite exhibited remarkable electrochemical performance, achieving a specific capacity of 630.5 mAh g⁻¹ at 1 A g⁻¹ – surpassing the performance of pristine Bi₂O₂Se (266.7 mAh g⁻¹) by a factor of 2.3. Notably, it achieved 60 % capacity retention at an ultra-high current density of 20 A g⁻¹ and maintains 73 % capacity retention after 5000 cycles, demonstrating outstanding cycling stability. These breakthroughs stem from the synergistic interplay between Bi₂O₂Se's interlayer architecture and PANI's pseudocapacitive properties. This work establishes the Bi₂O₂Se/PANI composite as a promising electrode material for next-generation supercapacitors and offers a versatile design framework for flexible electronics and grid-scale renewable energy storage systems.