Halochromic Cotton Fabrics Prepared by layer-by-layer Assembly

Halochromic cotton fabrics were fabricated based on a layer-by-layer technique. The formation of multiple layers from polyelectrolytes with opposite charges was confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. UV-vis spectroscopy and color analysis revealed that the obtained fabrics produce a clear and rapid color response. The color change is reversible, and the switching process can be repeated 10 times. It was also found that dyes located in the surface layers were more likely to leach when immersed in NaCl solutions. Due to its efficiency and simplicity, this halochromic cotton fabric could be utilized as a naked-eye sensing label or test strip to monitor pH.

Automated summary

Halochromic cotton fabrics were fabricated using a layer-by-layer technique, and showed a clear and rapid color response. The color change is reversible and can be repeated multiple times, making it suitable for pH monitoring.