Exploring the potentials of delafossite-coated cotton textiles: photocatalytic self-cleaning, UV-blocking, antimicrobial activity, and hydrophobicity

Delafossite materials demonstrate multifunctional applications due to their excellent catalytic properties, which vary depending on their morphology, particle size, and synthetic method. Herein, a few novel applications of the delafossites are reported, which can be implemented in commercial, medical, and domestic settings. In the present work, we are presenting two different delafossites, CuGaO₂ and CuFeO₂ nanoparticles, and their composite with cotton fiber. Multifunctional cotton fabric is prepared by depositing a uniform coating layer of CuGaO₂ and CuFeO₂ and exhibits excellent photocatalytic self-cleaning, UV blocking, antimicrobial activity, and hydrophobicity. CuGaO₂ and CuFeO₂ nanoparticle concentrations of 1 mM and 2 mM were deposited over the cotton fabric using citric acid as a binder by a simple sonication method. Surface analysis, bindings, stability, stain resistance, and UV blocking characteristics of the functionalized cotton fabric are performed by SEM, EDX, XRD, FTIR, and UV–Vis spectroscopy. Both CuGaO₂-cotton and CuFeO₂-cotton exhibit excellent photocatalytic activity, which is evident from the UV–Vis spectroscopic analysis after mixing with methylene blue dye and subsequent exposure to simulated solar light. In addition, CuGaO₂-cotton and CuFeO₂-cotton block most of the harmful UV radiation, 95–97.5% (approx.) in the case of CuGaO₂ and 90% (approx.) in the case of CuFeO₂. The modified cotton fabrics present good antimicrobial activity against gram-positive and gram-negative bacteria, which is confirmed by antimicrobial tests with Staphylococcus aureus and E. coli bacteria. The newly fabricated cotton-delafossite composite, with all its promising applications, can be viewed as a valuable, sustainable contribution of materials science to humanity.

Graphical Abstract