In situ engineered α-MnSe/Bi2Ni3Se2 electrodes enabling ultra-stable, wide-potential quasi-solid-state hybrid supercapacitors for wearable electronics

Abstract

Recent advancements in energy storage technology highlight the potential of mixed-metal multiphase selenides (MMSes) as promising electrode materials due to their strong redox activity, stability, cost-effectiveness, and superior conductivity. In this study, an ultra-thin nanosheet (UTNS) MMSe, consisting of α-MnSe (MnSe) and Bi2Ni3Se2 (BNSe), is successfully synthesized on nickel foam via an in situ hydrothermal method. This straightforward yet effective approach significantly enhances electrochemical performance. The UTNS morphology of these MMSes plays a pivotal role in achieving high specific capacitance and exceptional cycling stability. In situ Raman spectroscopy and density functional theory calculations confirm the participation of dual elements in the redox reaction, enabling efficient electrochemical energy storage and release. Notably, the MnSe/BNSe electrode retains nearly its entire initial capacity even after 10,000 charge-discharge cycles, underscoring the advantages of UTNSs in providing a large surface area and facilitating shorter ion diffusion pathways—both crucial for stable and rapid charge-discharge processes in modern energy storage devices (ESDs). Furthermore, the fabrication and evaluation of the MnSe/BNSe//activated carbon quasi-solid-state hybrid supercapacitor demonstrate the practical feasibility of these materials, exhibiting remarkable specific energy and specific power characteristics. These findings reinforce the potential of MnSe/BNSe-based electrodes for next-generation high-performance ESDs. © 2025 Elsevier B.V.