In the quest for sustainable and efficient materials, a team of researchers from the National University for Science and Technology POLITEHNICA Bucharest has made a significant breakthrough. Led by Ionela-Cristina Petcu from the Faculty of Chemical Engineering and Biotechnologies, the team has developed an environmentally friendly method for synthesizing Ag-TiO2 composites using pulsed reverse current (PRC) electrodeposition from deep eutectic solvents (DESs). This innovation could revolutionize the energy sector by enhancing photocatalytic processes and antibacterial applications.
The study, published in Applied Surface Science Advances, explores the synthesis of Ag-TiO2 composites, a material with promising applications in environmental remediation and energy production. The use of DESs, which are non-toxic and cost-effective, marks a departure from traditional methods that often rely on hazardous chemicals. “The combination of PRC and DESs offers better control over nanoparticle synthesis while eliminating the need for toxic or expensive precursors,” Petcu explained. This approach not only reduces environmental impact but also opens up new possibilities for scalable and sustainable production.
The researchers employed various analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), to investigate the structure and morphology of the composite. TEM analysis revealed that silver nanoparticles (Ag NPs) are effectively attached to TiO2 nanopowder, confirming the successful integration of the two materials. The UV–Vis diffuse reflectance spectra (DRS) displayed a broad peak in the range of 400 – 650 nm, indicative of the localized surface plasmon resonance (LSPR) of Ag NPs on the semiconductor’s surface. This resonance is crucial for enhancing the material’s photocatalytic properties.
The photocatalytic activity of the Ag-TiO2 composite was evaluated based on the degradation of methyl orange (MO) dye under UV and visible light illumination. The results were striking: the incorporation of Ag significantly improved the photocatalytic efficiency. This enhancement is attributed to the synergistic effects of Ag NPs and TiO2, which together facilitate the generation of superoxide radicals (•O2−), the primary drivers of the degradation process.
Beyond photocatalysis, the Ag-TiO2 composite also demonstrated superior antimicrobial activity against both Gram-positive (B. subtilis) and Gram-negative (E.coli) bacteria. This dual functionality makes the material an attractive candidate for applications in water treatment, air purification, and even medical devices, where both photocatalytic and antibacterial properties are desirable.
The implications of this research are far-reaching. In the energy sector, efficient photocatalytic materials are crucial for developing sustainable energy solutions, such as solar-driven water splitting and pollutant degradation. The enhanced antibacterial properties could also lead to the development of self-cleaning surfaces and antimicrobial coatings, reducing the need for chemical disinfectants.
As the world seeks to transition to a more sustainable future, innovations like the Ag-TiO2 composite synthesized by Petcu and her team represent a significant step forward. By leveraging green electrolytes and advanced electrochemical techniques, researchers are paving the way for a new generation of materials that are both environmentally friendly and highly effective. This research, published in Applied Surface Science Advances, which translates to Advanced Studies in Surface Science, underscores the potential for groundbreaking discoveries at the intersection of materials science and environmental engineering. As industries continue to explore these frontiers, the future of sustainable technology looks increasingly bright.