A way to measure droplets on hydrophilic surfaces wins Innovation Prize at Department of Applied Physics

The Department of Applied Physics at Aalto University is an efficient machine churning out new papers, innovations, and aspiring entrepreneurs. Since 2020, the department has awarded its Innovation Prize to staff members who have produced an invention with scientific, commercial, or societal impact – or, better yet, a combination of all three.

In 2022, the recipient was doctoral candidate Heikki Nurmi, who created an invention with a potentially huge impact on the way we understand wetting on hydrophilic—that is, prone-to-wetting—surfaces. The challenge Nurmi’s innovation rises to meet is the difficulty of measuring wetting on very hydrophilic surfaces. It’s a problem that various industries in Finland and the world over struggle with; from HVAC to maritime to biomedical applications.

“Wetting is typically measured with the shape of water droplets. If the surface the water is applied to is very hydrophobic, the droplet is more or less a ball; if the surface is hydrophobic or hydrophilic, the droplet is a spherical cap; and for very hydrophilic surfaces the droplet is either a extremely thin cap or a flat strip of water. This innovation focuses on measuring the droplet on hydrophilic surfaces, which has so far been extremely challenging to do,” Nurmi says.

Encouragement and inspiration

Nurmi’s research ties in closely with the main focus areas of Aalto’s Department of Applied Physics, which include the study of surfaces and wetting. According to Nurmi, his invention is based on many of the same ideas, equations, and approaches the department works with. He says that the invention emerged naturally from pursuing his own scientific curiosity. And he never had to work alone.

“The people I work with are crucial for helping to bring ideas to life. For example, this invention would not exist without Professor and Head of Department Robin Ras, who supported me when I explained my idea to him,” Nurmi says. For Nurmi, the department is the perfect environment for pursuing his scientific and entrepreneurial curiosity. University Lecturer Janne Halme, who coordinated the call for the nominations, says that Nurmi’s work is an example of how fostering innovators is more important than individual innovations. The Innovation Prize is one such example of encouraging and inspiring the staff and students to realise their vision.

And that is exactly what Heikki Nurmi is doing. If all goes according to plan, Nurmi will move to patent and eventually found a startup around the pioneering invention.