Developing materials and applications based on interpenetrating networks

Interpenetrating networks (IPNs) are considered to be a good candidate of functional materials which can achieve the combined advantages from different materials. They refer to a family of composites that contain two or more inter-lock materials with different properties. IPNs and the derived materials are demonstrating vast potential in applications such as sensing, actuation, and energy conversion and storage, yet there are many scientific and engineering challenges in both the synthesis and the practical implementation.

This project is focusing on the chemistry, materials science and engineering aspects of IPNs with recent advances in conducting polymers. Application-wise, we are developing multifunctional IPNs which can be used both as a haptic sensor and an actuator. In development is a device that can sense a physical contact with both normal pressure and a directional shear component, which is currently difficult to achieve. In addition, information is also expected to be conveyed from the system to the external environment via low-voltage electric actuation.

Another goal of the project is to design and synthesise novel functional nanomaterials based on IPNs. We recently managed to synthesise a novel nano-IPN composed of a chemically and thermally stable conducting polymer and a metal-organic framework (MOF). We also obtained a polymer nanostructure developed from the nano-IPN with unprecedented high surface area, while maintaining conductivity. We are currently improving the synthetic approaches and characterisations of both materials.

By scaling interpenetration down to the nano-scale, we believe we can overcome many diffusion limitations of current actuators and sensors, so we could greatly speed up the haptic sensing and actuation responses of existing materials. Such a speed-up, in combination with other sensing or functionality, could give rise to qualitatively new interactions and self-contained autonomous behaviour of materials. Other applications such as supercapacitor and electro-catalysis for low-temperature fuel cells could also benefit from the development of such materials.