Ultrasoft Core–Shell Inorganic Nanoyarns for Energy and Sensing Applications

Abstract

Inorganic nanoyarns with high electrical conductivity, tunable redox activity, and outstanding chemical/thermal stability are promising components for high-performance multifunctional fibers. However, integrating inorganic functionality with the softness, durability, and processability required for wearable fiber systems remains a major challenge. Here we present ultrasoft core–shell nanoyarns composed of inorganic nanoribbon cores and polymer shells with exceptional mechanical compliance while maintaining high electrical and chemical performance. The inorganic core provides multifunctionality and structural diversity with single-layer, particle-decorated, and multilayer sandwich architectures. A grounded-core electrospinning strategy is introduced to form porous polymer shells around the inorganic cores, providing mechanical reinforcement, electrical insulation, and diffusion pathways for reactive species within a resilient, flexible framework. The proposed core–shell nanoyarns function as efficient water-splitting electrodes, deliver a high volumetric energy density in fiber-type supercapacitors, and operate as force sensors capable of detecting forces at the tens-of-micronewton level. These results establish the core–shell nanoyarn as a universal and scalable platform for wearable energy and sensing systems.

Graphical Abstract

Keywords

Core–shell nanoyarns / Inorganic nanoribbons / Electrospinning / Water-splitting / Fiber supercapacitors / Wearable sensors

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Funding

Ministry of Science and ICT, South Korea(RS-2025-00521316)

National Research Foundation of Korea(RS-2023-00248902)

Ministry of Trade, Industry and Energy(RS-2022-00154781)

Ministry of Education(RS-2025-25414424)

Hanbat National University

Korea Evaluation Institute of Industrial Technology(1415179744)

Rights & permissions

Donghua University, Shanghai, China

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