Interface-centric strategies in Nb2O5/MoS2 heterostructure: Leveraging synergistic potential for dual-function electrochromic energy storage

The advancement of multifunctional materials integrating electrochromic and energy storage functionalities represents a transformative approach to next-generation energy systems. This study reports the Nb2O5/MoS2 heterostructure thin films, fabricated via a hydrothermal method, for dual electrochromic energy storage applications. The optimized heterostructure leverages the complementary properties of Nb2O5 and MoS2, attaining unrivaled performance in both domains. The electrochemical determinations reveal that the Nb@Mo20 exhibits an areal capacitance of 176.74 mF/cm2 at 0.8 mA/cm2, alongside magnificent cycling stability. Owing to its favorable structural characteristics, the heterostructure unveiled striking optical modulation of 77.11 % at 600 nm, transitioning between 82.25 % (bleached) and 5.14 % (colored) states. It delivered rapid switching times, with a high coloration efficiency of 98.92 cm2/C. Long-term cycling stability conveyed minimal performance loss after 20,000 s, ensuring sustained efficiency. Additionally, a hybrid electrochromic supercapacitor is developed, demonstrating a notable optical contrast (73.60 % at 600 nm), acceptable capacitance with good cycling stability. The device maintains a wide voltage range, effectively powering LEDs, showcasing scalability for real-world applications. The design principles outlined in this study offer valuable insights into the development of high-performance electrochromic energy storage materials, highlighting their potential applications in energy efficiency and storage.