A Self-Assembled 2D Thermofunctional Material for Radiative Cooling

[EN] The regulation of temperature is a major energy-consuming process of humankind. Today, around 15% of the global-energy consumption is dedicated to refrigeration and this figure is predicted to triple by 2050, thus linking global warming and cooling needs in a worrying negative feedback-loop. He...

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Detalhes bibliográficos
Autores: Jaramillo-Fernandez, Juliana, Whitworth, Guy L., Pariente González, J. Ángel, Blanco Montes, Álvaro, García Fernández, Pedro David, López, Cefe, Sotomayor Torres, C. M.
Formato: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2019
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/218134
Acesso em linha:http://hdl.handle.net/10261/218134
Access Level:acceso abierto
Palavra-chave:Radiative cooling
Self-assembled single-layer crystals
Silica
Thermofunctional materials
Ultra-broadband thermal emitters
Descrição
Resumo:[EN] The regulation of temperature is a major energy-consuming process of humankind. Today, around 15% of the global-energy consumption is dedicated to refrigeration and this figure is predicted to triple by 2050, thus linking global warming and cooling needs in a worrying negative feedback-loop. Here, an inexpensive solution is proposed to this challenge based on a single layer of silica microspheres self-assembled on a soda-lime glass. This 2D crystal acts as a visibly translucent thermal-blackbody for above-ambient radiative cooling and can be used to improve the thermal performance of devices that undergo critical heating during operation. The temperature of a silicon wafer is found to be 14 K lower during daytime when covered with the thermal emitter, reaching an average temperature difference of 19 K when the structure is backed with a silver layer. In comparison, the soda-lime glass reference used in the measurements lowers the temperature of the silicon by just 5 K. The cooling power of this simple radiative cooler under direct sunlight is found to be 350 W m when applied to hot surfaces with relative temperatures of 50 K above the ambient. This is crucial to radiatively cool down devices, i.e., solar cells, where an increase in temperature has drastic effects on performance.