Textination Newsline

Imagine a coat that captures solar energy to keep you cozy on a chilly winter walk, or a shirt that can monitor your heart rate and temperature. Picture clothing athletes can wear to track their performance without the need for bulky battery packs.

University of Waterloo researchers have developed a smart fabric with these remarkable capabilities. The fabric has the potential for energy harvesting, health monitoring and movement tracking applications.

The new fabric can convert body heat and solar energy into electricity, potentially enabling continuous operation with no need for an external power source. Different sensors monitoring temperature, stress and more can be integrated into the material.

It can detect temperature changes and a range of other sensors to monitor pressure, chemical composition and more. One promising application is smart face masks that can track breath temperature and rate and detect chemicals in breath to help identify viruses, lung cancer and other conditions.

“We have developed a fabric material with multifunctional sensing capabilities and self-powering potential,” said Yuning Li, a professor in the Department of Chemical Engineering. “This innovation brings us closer to practical applications for smart fabrics.”

Unlike current wearable devices that often depend on external power sources or frequent recharging, this breakthrough research has created a novel fabric which is more stable, durable, and cost-effective than other fabrics on the market.

This research, conducted in collaboration with Professor Chaoxia Wang and PhD student Jun Peng from the College of Textile Science and Engineering at Jiangnan University, showcases the potential of integrating advanced materials such as MXene and conductive polymers with cutting-edge textile technologies to advance smart fabrics for wearable technology.

Li, director of Waterloo’s Printable Electronic Materials Lab, highlighted the significance of this advancement, which is the latest in the university’s suite of technologies disrupting health boundaries.

“AI technology is evolving rapidly, offering sophisticated signal analysis for health monitoring, food and pharmaceutical storage, environmental monitoring, and more. However, this progress relies on extensive data collection, which conventional sensors, often bulky, heavy, and costly, cannot meet,” Li said. “Printed sensors, including those embedded in smart fabrics, are ideal for continuous data collection and monitoring. This new smart fabric is a step forward in making these applications practical.”

The next phase of research will focus on further enhancing the fabric’s performance and integrating it with electronic components in collaboration with electrical and computer engineers. Future developments may include a smartphone app to track and transmit data from the fabric to healthcare professionals, enabling real-time, non-invasive health monitoring and everyday use.

The study is published in the Journal of Materials Science & Technology.

Imagine a truck tarp that can harvest the energy of sunlight!
With the help of new textile-based solar cells developed by Fraunhofer researchers, semitrailers could soon be producing the electricity needed to power cooling systems or other onboard equipment. In short, textile-based solar cells could soon be adding a whole new dimension to photovoltaics, complementing the use of conventional silicon-based solar cells. Solar panels on building roofs are a common enough sight today – as are large-scale solar parks. In the future, we may well see other surfaces being exploited for photovoltaic generation. Truck tarps, for example, could be used to produce the electricity consumed by the driver when underway or parked up for the night, or to power electronic systems used to locate trailers in shipping terminals. Similarly, conventional building facades could be covered with photovoltaic textiles in place of concrete render. Or the blinds used to provide shade in buildings with glass facades could be used to create hundreds of square meters of additional surface for producing power.

Glass-fiber fabric as a solar-cell substrate
At the heart of such visions are pliable, textile-based solar cells developed at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in collaboration with the Fraunhofer Institute for Electronic Nano Systems ENAS, Sächsisches Textilforschungsinstitut e.V and industrial partners erfal GmbH & Co. KG, PONGS Technical Textiles GmbH, Paul Rauschert GmbH & Co. KG and GILLES PLANEN GmbH. “There are a number of processes that enable solar cells to be incorporated in coatings applied to textiles,” explains Dr. Lars Rebenklau, group manager for system integration and electronic packaging at Fraunhofer IKTS. In other words, the substrate for the solar cells is a woven fabric rather than the glass or silicon conventionally used. “That might sound easy, but the machines in the textile industry are designed to handle huge rolls of fabric – five or six meters wide and up to 1000 meters in length,” explains Dr. Jonas Sundqvist, group manager for thin-film technology at Fraunhofer IKTS. “And during the coating process, the textiles have to withstand temperatures of around 200 °Celsius. Other factors play a key role too: the fabric must meet fire regulations, have a high tensile strength and be cheap to produce. “The consortium therefore opted for a glass-fiber fabric, which fulfills all of these specifications,” Rebenklau says.

An emphasis on standard processes
Researchers also faced the challenge of how to apply the wafer-thin layers that make up a solar cell – the bottom electrode, the photovoltaic layer and the top electrode – to the fabric. These layers are between one and ten microns in thickness. By comparison, the surface of the fabric is like a mountain range. The solution was first to apply a layer that levels out the peaks and troughs on the surface of the fabric. For this purpose, researchers opted for a standard process from the textile industry: transfer printing, which is also used to rubberize fabrics. All the other processes have been adapted in such a way that they can be easily incorporated in standard production methods used in the textile industry. For example, the two electrodes – which are made of electrically conductive polyester – and the photovoltaic layer are applied by means of the common roll-to-roll method. The solar cells are also laminated with an additional protective layer in order to make them more robust.

Fabric-based solar cells ready for market launch in around five years
The research team has already produced an initial prototype. “This has demonstrated the basic functionality of our textile-based solar cells,” Rebenklau says. “Right now, they have an efficiency of between 0.1 and 0.3 percent.” In a follow-up project, he and the team are seeking to push this over the five percent mark, at which point the textile-based solar cells would prove commercially viable. Silicon-based solar cells are significantly more efficient, at between ten and 20 percent. However, this new form of solar cell is not intended to replace the conventional type, merely offer an alternative for specific applications. In the coming months, the team will be investigating ways of enhancing the service life of the fabric-based solar cells. If all goes according to plan, the first textile-based solar cells could be ready for commercialization in around five years. This would fulfill the original goal of the PhotoTex project: to provide new stimulus for Germany’s textile industry and improve its competitiveness.