The project “New Generation of Chromogenic Materials for Smart Windows (NIRGLASS)” has been awarded with an INNOVADORS grant for innovative projects with potential for being incorporated into the production sector, granted by the AGAUR (Agència de Gestió d’Ajuts Universitaris i de Recerca, Generalitat de Catalunya), FEDER (Fons Europeu de Desenvolupament Regional) and Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya.
The present project aims to develop a novel type of smart material that when subjected to the near-infrared (NIR) radiation deriving from the sunlight, self-modulates the transmission of the incident visible and/or NIR radiation. The integration of this class of material in glasses of buildings is expected to increase both comfort (better illumination conditions in the rooms) and energy efficiency of the building (less use of airconditioning/heating devices), in the same fashion as other commercialized products. However these materials do not need circuits or electrical power supply, are activated by harmless NIR irradiation (which should increase significantly the fatigue resistance of the material) and can smartly modulate transmission of both visible and NIR radiation. Given these advantages, they could supplant the already commercialized materials, for the increase of comfort and energy efficiency in future buildings, that often lack of photostability and coverage of modulation of NIR (as for photochromic materials), are strictly dependent on temperature (thermochromic systems) or are not cost-effective for their installation, renewal and maintenance (electrochromics or liquid crystals based technologies).
The material proposed in this project is based on a technology recently developed in the Nanosfun group. This project aims to obtain highly photostable transparent films that undergo NIR-induced modulation of the absorption properties providing an increase of comfort and energy efficiency, compared to commercialized technologies.
Conceptually, the technology relies on the use of phase-change-materials (PCMs), incorporating dyes that change their optical properties (i.e. absorption/transmittance) significantly when the PCM passes from the solid to the liquid state. In this technology, the PCM melting is achieved through the heat produced by the NIR irradiation of nanoparticles (NPs) able to transform the incident light into heat (e.g. noble metal, semiconducting polymer NPs, etc.). Consequently, the NIR irradiation of the material produces local heating around the NPs through the photothermal effect. The temperature increase induces the melting of the PCM and therefore, variations of the absorption properties of the dye. Once the NIR radiation is ceased, the material recovers the initial state.
Dr. Claudio Roscini (Principal Investigator)
Jaume Ramón Otaegui Rabanal (PhD student)
Dr. Daniel Ruiz-Molina (Group Leader)
This project has been co-financed by the European Union through the European Regional Development Fund (ERDF).
(Grant Number: 2019 INNOV 00070)