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Material scientists can take inspiration from how nature works at the both the microscopic and macroscopic level to inform their work when designing new or honing existing materials. The field, dubbed bio- or life-inspired materials, has a wide impact outside of just material science, providing new insights to, for example, robotics, medicine, and flexible electronics.

Since his introduction 91����� in 2017, Dr. Hang Zhang, currently a Research Fellow and leader of the Life-Inspired Soft Matter group at the Department of Applied Physics, has been working with soft matter, i.e., matter that is not metal, rock or similar “hard stuff”. His particular interests are hydrogels, mixtures of solid matter and liquid water, at various length scales beginning in the nanometer realm, and how to apply those gels to light-driven soft systems.

‘Living systems such as plants or microscopic bacteria provide an unlimited source of inspiration due to their complex responses, self-regulation, dissipation of energy, adaptive behaviors, and feedback control,’ Zhang says.

Alternate dimensions

He has now been awarded a prestigious European Research Council (ERC) Starting Grant worth 1.5 million euros over 5 years to set up a project called DIMENSION. The aim is to bring about a breakthrough in soft materials science by introducing coupled physical feedback loops in hydrogels that are applicable in one-, two- and three-dimensional geometries.

‘This ERC grant will further promote my research along the line of life-inspired materials, by digging deeper into the aspect of complex feedback control in hydrogel-based soft materials. It is an aspect that has often been overlooked before in intelligent and bio-inspired materials,’ Zhang says.

With the grant, Zhang and his team will create hydrogel systems that are powered by a laser beam controlled by built-in feedback mechanisms. The feedback mechanism will help the hydrogels sense external stimuli and respond correspondingly, resulting in adaptivity, self-regulation, and life-inspired responses. The team’s unique twist is complex feedback control at increased dimensionality.

‘Previously known systems like this are often limited to specific dimensions due to the intricate stimulus-material interactions, which does not allow much room for adjustment and fine-tuning. This project develops coupled feedback-controlled systems across different dimensionalities, from 1D to 3D, thus providing different model systems of coupled feedback control and new approaches of tuning their dimensionality,’ he says.

Beyond physics and chemistry

Zhang is confident that DIMENSION will provide entirely new ways of building feedback loops in soft materials. Researchers and engineers are then able to use this to realize new soft materials that have higher adaptivity, self-regulation and more complex functionalities than previous ones.

The applications proliferate far beyond fundamental chemistry and physics. Fields that can make use of the new ways of designing soft materials include robotics, bio-medicine, and flexible electronics, to name a few.

‘The implementation of these model systems will help us gain deeper insights into realizing complex feedback control in soft materials and take a step further towards the grand challenge of implementing truly life-inspired, dissipative, self-regulated, and adaptive functionalities in synthetic materials,’ Zhang says.

The European Research Council funding is awarded to leading researchers for pioneering work at the frontiers of science. The ERC Starting Grants are designed to support talented scientists in the early stages of their career.