World’s First ‘Nano Inks’ Control Temperatures in Buildings, Cars

By Sunny Lewis for Maximpact

MELBOURNE, Australia, August 31, 2023 (Maximpact.com Sustainability News) – Pioneering “phase change inks” that use nanotechnology to control temperatures in everyday environments have been developed at the University of Melbourne. Ten research scientists there say these special inks have the potential to reduce the energy used to heat and cool buildings, homes and cars and could slash global greenhouse gas emissions.

Their research has documented proof-of-concept phase change inks that can achieve sophisticated “passive climate control.” Led by Dr. Mohammad Taha of the University of Melbourne, the study is published in The Royal Society of Chemistry’s “Journal of Materials Chemistry A.”

“These inks can adjust the amount of radiation that can pass through them, based on the surrounding environment, and could be used to develop coatings for buildings that enable passive heating and cooling – reducing our need to rely on energy creation to regulate environments,” Dr. Taha explained in an article published by the university.

He says that passive climate control can reduce the severity of extreme climate conditions and help create comfortable living situations without expending energy unnecessarily.

Materials that are able to store and release a considerable amount of heat are called phase change materials. An example of a phase change material is water, which can change from the liquid phase to a solid phase, as ice, or a vaporous phase, as steam.

The new versatile “phase change inks” can be laminated, sprayed or added to paints and building materials. They could also be incorporated into clothing, regulating body temperature in extreme environments.

The specialty inks also could be used in the creation of large-scale, flexible and wearable electronic devices like bendable circuits, cameras and detectors, and gas and temperature sensors, he said.

Dr. Taha sees the potential for these inks to be used in coatings to achieve passive heating and cooling, reducing the need to rely on energy generation to regulate temperatures.

“Humans use a lot of energy to create and maintain comfortable environments – heating and cooling our buildings, homes, cars and even our bodies,” Dr. Taha said. “We can no longer only focus on energy generation from renewable resources to reduce our environmental impact. We also need to consider reducing our energy consumption as part of our proposed energy solutions, as the impacts of climate change become a reality.”

Passive climate control would enable comfortable living conditions while saving energy. To provide comfortable heating in winter, for instance, nano inks applied on a building façade could automatically transform to allow greater sun radiation to pass through during the day, and greater insulation to keep warmth in at night.

In summer, they could transform to create a barrier that would block heat radiation from the sun and the surrounding environment.

“By engineering our inks to respond to their surroundings, we not only reduce the energy expenditure, but we also remove the need for auxiliary control systems to control temperatures, which is an additional energy waste,” Dr. Taha said.

The team has produced printable material – a proof-of-concept that’s versatile and adaptable. “It can be laminated, sprayed or added to paints and building materials. These semiconductors can also be incorporated into clothing, regulating body temperature in extreme environments, or in the creation of large-scale, flexible electronic devices,” the Melbourne scientist explained.

“The potential of this material is huge as it can be used for so many different purposes, like preventing heat build-up in laptop electronics or protecting car windshields,” Dr. Taha said. “The beauty of this material is that we can adjust its heat absorption properties to suit our needs.”

“Our research removes the previous restrictions on applying these inks on a large scale cheaply,” he explained. “It means existing structures and building materials can be retrofitted.”

Dr. Taha explains that a different type of phase change material is used right now to manufacture smart glass, “But our new material means we can engineer smarter bricks and paint,” he said.

The company, GlassX based in Zurich, Switzerland, manufactures the smart glass. “By using phase change material in the glazing, we bring seemingly incompatible building material properties together: translucency, low U-value, variable g-value and high thermal mass,” the company says on its website.

The core of the GLASSX products is a thin layer of translucent phase change material; 15 millimeters of this material can absorb as much heat as a 25 centimeter concrete wall at room temperature, the company says. This unique property makes it possible to replace solid exterior walls in a building with translucent glass elements.

This new nanotechnology can help retrofit existing buildings to make them more efficient and sustainable. The breakthrough was achieved by discovering how to modify one of the main components of phase change materials, vanadium oxide (VO2).

Phase change materials use triggers, like heat or electricity, to create enough energy for the material to transform itself under stress. But phase change materials previously needed to be heated to very high temperatures for their phase changing properties to be activated.

“We used our understanding of how these materials are put together to test how we could trigger the insulator to metal reaction, where the material basically acts as a switch to block heat beyond a particular temperature – near-room temperature 30-40 degrees Celsius,” Dr. Taha said.

This research has been patented by the University of Melbourne, and now the next step is to take the proof-of-concept into production, a process that Dr. Taha says will be “affordable and simple.”

With interest from manufacturers, he projects, the nano inks could reach market in five to 10 years.

The scientist sees vast potential for the new phase change inks. “Through collaboration with industry,” he plans, “we can scale up and integrate them into existing and new technologies as part of a holistic approach to tackling the world’s climate change energy challenges.”

Dr. Taha attributes his success to a fierce work ethic and a genuinely open mind. The research fellow was named one of Engineers Australia’s 30 Most Innovative in 2019 two years after completing his PhD.

“I am fascinated by novel materials and their potential,” he says. “I get to make cool flexible electronics and pursue my passion for the environment and sustainability.”