Light-Activated Superhydrophobicity of Sustainable Micro-Structured Spent Coffee Grounds-Based Interfaces via Fatty Acids Modulation
Zargarian, Seyed Shahrooz (Polish Academy of Sciences)
Suárez García, Salvio (Institut Català de Nanociència i Nanotecnologia)
Saiz-Poseu, Javier (Institut Català de Nanociència i Nanotecnologia)
Zuppiroli, Luca (Università di Bologna)
Lanzi, Massimiliano (Università di Bologna)
Ruiz-Molina, Daniel (Institut Català de Nanociència i Nanotecnologia)
Pierini, Filippo (Polish Academy of Sciences)

Date:	2025
Abstract:	The global consumption of coffee results in the disposal of vast amounts of spent coffee grounds (SCG), posing significant environmental challenges. Herein, we address this issue by developing an innovative, eco-friendly method to achieve superhydrophobicity using SCG. Repurposing this abundant biowaste, we developed a sustainable approach that avoids the use of harsh chemicals and energy-intensive processes typically associated with conventional methods. Our procedure involves wet ball milling of SCG in ethanol to produce microparticles, followed by electrospraying to create a micro-structured interface. A mild annealing treatment at 90 °C successfully transformed the SCG interface from hydrophilic to superhydrophobic, reaching a contact angle of approximately 151° and a rolling-off angle of 8°. The resultant interface exhibited remarkable self-cleaning properties, effectively repelling various liquids. XPS analysis revealed that the migration of fatty acids to the surface during annealing played a crucial role in lowering surface energy, thereby driving the hydrophilic-to-superhydrophobic transition. Furthermore, we demonstrated that solar-induced heating can effectively activate the same superhydrophobic properties, providing a practical and energy-efficient alternative to traditional thermal treatments. This method illustrates the role of light-activated fatty acid modulation in achieving superhydrophobicity and highlights the potential of SCG biowaste as a valuable resource for sustainable material applications.
Grants:	European Commission 101068036 Agencia Estatal de Investigación PID2021-127983OB-C21 Agencia Estatal de Investigación CEX2021-001214-S
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya
Rights:	Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets.
Language:	Anglès
Document:	Article ; recerca ; Versió sotmesa a revisió
Published in:	ChemSusChem, Vol. 18, Num. 10 (May 2025) , art. e202402254, ISSN 1864-564X

DOI: 10.1002/cssc.202402254

Preprint 26 p, 1.2 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles