A research team from Shinshu University has developed a low-cost nanocomposite by embedding trimetallic and bimetallic molybdates into hollow carbon nanofibers doped with fluorine, boron, and nitrogen. The composite demonstrates promising dual functionality for energy storage and environmental remediation, offering a scalable and effective solution to pressing global energy and pollution challenges.
Energy demand and environmental sustainability remain urgent global concerns. Rapid urbanization, industrialization, and population growth—particularly in developing countries—have led to rising energy consumption and increased water pollution.
In response, there has been growing interest in multifunctional nanostructured materials that can address both energy storage and environmental issues. Bimetallic and ternary metal molybdates have emerged as strong candidates due to their catalytic and electrochemical properties.
However, current methods for producing such nanocomposites often have major drawbacks. Many rely on expensive carbon materials like carbon nanotubes or graphene, while others use complex, time-consuming, or environmentally harmful synthesis techniques. Some methods also require large quantities of metals, typically over 50 % by weight, making them less practical for real-world applications, especially in resource-limited settings.
Led by Distinguished Professor Ick Soo Kim from the Nano Fusion Technology Research Lab, the study also involved Dr. Gopiraman Mayakrishnan and Dr. Azeem Ullah from Shinshu University, along with Dr. Ramkumar Vanraj from Yeungnam University.
The team anchored ultrafine bimetallic (FeMo) and ternary (NiCoMo) molybdates onto hollow-core carbon nanofibers doped with fluorine, boron, and nitrogen. The hollow structure increases the available surface area for reactions, while the dopants enhance the carbon scaffold’s conductivity and chemical reactivity.
We have created a multifunctional platform that is not only scalable and cost-efficient but also delivers exceptional performance in energy storage. Our approach reduces the reliance on expensive metals, and the doping of the carbon nanofibers enhances their properties, allowing us to create a material that can serve both energy and environmental needs.
Ick Soo Kim, Distinguished Professor, Shinshu University
The primary goal of testing the new nanocomposite material was to evaluate its potential for improving energy storage. It demonstrated a specific capacitance of 1,419.2 F/g, significantly higher than that of many existing materials used for energy storage applications.
The material also showed strong durability, retaining 86 % of its initial capacity after 10,000 charge-discharge cycles, a key factor for the long-term reliability of energy storage systems.
Beyond its energy storage performance, the nanocomposite also showed promise in environmental applications. The researchers tested its ability to catalyze the reduction of 4-nitrophenol, a toxic compound commonly found in industrial wastewater.
The results indicated high efficiency in degrading this pollutant, suggesting potential use in pollution control and water purification systems.
In addition to its performance, the nanocomposite is relatively inexpensive to produce. Traditional nanomaterials often require large amounts of metals or costly components like graphene, which can increase manufacturing costs. In contrast, the new material benefits from a simpler synthesis process and reduced metal content, making it more cost-effective for large-scale deployment.
With its combination of high performance, lower production cost, and scalability, the nanocomposite represents a strong candidate for various applications. While the findings mark a significant step toward sustainable nanotechnologies, further research and development will be needed before the material is ready for commercial use.
The next step is to refine the production process and test the material in more diverse conditions. We also plan to explore its potential in other environmental applications, such as the removal of different types of pollutants.
Ick Soo Kim, Distinguished Professor, Shinshu University
Journal Reference:
Mayakrishnan, G., et al. (2025) Inner–Outer Surface Anchoring of Ultrafine Bi(Tri)-Metallic Molybdates on N-, B-, and F-Doped Hollow-Core Carbon Nanofibers: Cost-Effective Nanocomposites with Low-Metal Loading for Energy and Environmental Applications. Advanced Fiber Materials. doi.org/10.1007/s42765-025-00528-7.
