Graphene-Based nanostructures and colloidal silver coatings for flexible cellulose substrates

Growing global critical concerns around public health and environmental protection demand for more even more effective and innovative technologies to mitigate these issues. Specifically, the rise of antibiotic-resistant bacteria and emerging microbial threats highlight the need for advanced antimicrobial solutions, while the widespread environmental presence of pharmaceutical contaminants introduces new monitoring challenges. To address these objectives, the scientific community is prioritizing zero-impact approaches in materials engineering, guided by sustainable and green chemistry principles. These adaptable and functional solutions are designed to perform effectively across diverse applications, aligning with Industry 4.0’s commitment to environmentally responsible and high-performance manufacturing. In this frame, the research activity of this PhD thesis focuses on developing innovative sustainable nanostructured and, as far as possible, Eco friend materials with multifunctional capabilities for fulfilling health and environmental concerns. This work introduces a novel hybrid nanocomposite based on Reduced Graphene Oxide (RGO), functionalized with the biocompatible amino acid histidine, and decorated with silver (Ag) nanostructures. By leveraging in situ and ex situ colloidal synthesis methods, and finely adjusting synthesis parameters, this research achieves a nanocomposite material, whose properties—including antimicrobial efficacy, thermal conductivity and SERS plasmonic properties—can be accurately tuned by controlling size and shape of the Ag nanostructures (nanoparticles - NPs - and nanowires – NWs -). Remarkably, these processes allow for solution-based integration of these nanocomposites into cellulose-based substrates like paper and cotton textiles. The development and application of the engineered nanocomposites is explored across three key fields: 1) antimicrobial coatings for textile, aimed at combating bacterial resistance, 2) flexible paper sensors for real-time monitoring of pharmaceuticals and pollutants in both environmental and biomedical settings, and 3) thermally conductive coatings for cotton fabrics, evaluating their suitability for use in wearable and flexible devices. Together, these applications highlight the versatile potential of nanocomposites in advancing sustainable, high-performance solutions for health and environmental challenges. The materials developed in this study highlight the integration embody of nanotechnology and sustainable chemistry, demonstrating how nanoscale modifications of structural and functional properties can greatly enhance versatility and performance. This approach not only advances adaptable, high-performing solutions but also emphasizes the critical role of nanoscience in fostering safer and more sustainable technologies, aligning with the United Nations Sustainable Development Goals (SDGs), particularly SDG 3 (Good Health and Well-being), SDG 6 (Clean Water and Sanitation), and SDG 12 (Responsible Consumption and Production). By addressing key health and environmental challenges, this research contributes to a safer, more sustainable technological landscape, supporting societal goals for resilience, well-being, sustainability, and public well-being.