From bendable solar cells to better batteries, cleantech has an ally in thin films

Thin films are enablers of the energy transition. Different examples were presented during a seminar organized by the High Tech Campus Eindhoven.

When thinking of thin films, chances are that the first thing you picture into your mind is your smartphone’s screen protector – 25 years ago, you would have probably thought of your camera’s film. Food-wrapping plastic might also be another use that comes to your mind. Well, these are only the tip of the iceberg: many more things can be done with thin films, whose utility greatly helps in producing green energy, capturing CO2, or storing power.

Speaking of materials and technology, a thin film is a material whose thickness is on the order of nanometers (nm) to micrometers (μm). These films are then deposited onto a substrate or surface, and their properties can cater to different applications. In electronics, for instance, thin films are used to fabricate semiconductor devices, circuits, and fine transistors. 

The Brainport region is a hotspot for research and development of thin film technologies. The Holst Centre – a research lab powered by leading Dutch and Belgian research institutes TNO and imec – is where many of these innovations came to be. Located at the High Tech Campus Eindhoven (HTCE), the lab continues to be an innovation hotspot. In spotlighting thin films tech, the HTCE organized a seminar on the topic, providing an overview of the current state of the technology with presentations and demos.

New solar energy solutions 

Solar technology is one of the domains benefitting the most from thin film developments. An example comes from HyET Solar, which developed Powerfoil, a flexible and low-cost photovoltaics module. This means it can efficiently convert sunlight into electricity. The flexibility of this technology allows it to be applied to various surfaces, enabling a more versatile and adaptable approach to harnessing solar energy.

To produce the modules, the Arnhem-based company developed a proprietary technology using a roll-to-roll method, with rolls of thin silicon solar films that attach to other foil substrates. HyET Solar was one of the companies showcasing its technology in a demo boot during the event. Powerfoil is a lightweight solution made with silicon solar cells, thus making it a low-cost solution. The company is further developing its concept, collaborating with TNO, which used thin film tech for another innovative solar cell application. 

During the event, Sjoerd Veenstra, Program Manager of Perovskite Solar Cells and Modules at TNO, presented an ivy-shaped thin film solar power system. One of the HTCE buildings is the testbed for the technology, standing as an example of deploying solar power on facades. In accelerating solar deployment, the research institute wants to optimize the production of thin film solar cells, possibly automating the processes using robots.

Conventional DAC tech works with porous materials that bind carbon when air is blown to them. Pores are filled with solvents that make sequestration easier yet inefficient. By contrast, using a thin film material allows a larger surface area where blow air can be blown in, improving the process efficiency while reducing the DAC device size. That’s what Carbyon is currently testing as it prepares to scale up its technology. 

Enabling transitions 

As research on thin films continues at the Holst Center and TNO, thin films will improve and remain powerful enablers. In addition to cleantech, applications in another critical domain, such as healthcare, can be found. Thinking of wearable technology, with devices that can keep track of body fluids. Thin films, wide impact.