Lecce – A team of Italian researchers from the Institute of Nanotechnology of the National Research Council (CNR-Nanotec) in Lecce, together with colleagues from France’s Paris-Saclay University (ENS Paris-Saclay), has developed an innovative material capable of changing color in response to environmental stimuli such as heat and electricity. The breakthrough opens new possibilities for smart windows, adaptive displays, and low-energy optical devices.
The material, detailed in a study published in Nano Energy, is based on two-dimensional perovskites embedded in a polymer gel. The research was carried out under European and Italian projects focused on sustainable transitions, advanced materials, and medical robotics.
“The innovation lies in a modular approach, similar to building with blocks: by adjusting the ratios between the main components – a copolymer and the perovskites – we can precisely control optical properties, activation temperature, and conductivity,” explains Vincenzo Maiorano, senior technologist at CNR-Nanotec and study coordinator.
The resulting gel serves as both an electrolyte and a chromogenic material, functioning within thermo-electrochromic devices (TECDs) that offer four distinct optical states depending on temperature and applied voltage. The device can modulate up to 75% of visible light transmittance – among the highest reported for such systems – and switches from transparent to colored in under a minute, returning to its original state within seconds. It also demonstrates stability and reversibility, even at high temperatures (up to ~80 °C), over repeated cycles without efficiency loss.
“Our next goal is to further lower the transition temperature and explore more sustainable 2D materials to make these devices even more efficient and application-ready,” adds Marco Pugliese, co-author and technologist at CNR-Nanotec. Fabrizio Illuminati, director of CNR Nanotec, concludes: “This study proves that a modular approach in materials science can generate flexible, sustainable solutions with tangible impacts on daily life.”