Fibre bio-nanocomposites and their applications in environmental chemistry

Fibre bio-nanocomposites have emerged as versatile analytical platforms for the detection and monitoring of environmental pollutants, owing to their tunable surface chemistry, high surface-to-volume ratios, and compatibility with diverse signal transduction mechanisms. This review critically examines recent advances in the design, fabrication, and functionalization of natural and synthetic fibre-based nanocomposites for environmental sensing applications. Particular emphasis is placed on analytical performance metrics, including sensitivity enhancement, selectivity control, detection limits, signal stability, and tolerance to complex environmental matrices in electrochemical, optical, and colorimetric detection systems. Representative sensing platforms are discussed for the quantitative determination of heavy metals, dyes, pesticides, and gaseous pollutants, with detection limits frequently reaching trace and ultra-trace levels. The review highlights clear structure–performance relationships, demonstrating how fibre morphology, nanoscale hybridisation, and surface modification govern charge transfer, mass transport, and signal reproducibility. Key challenges related to matrix interference, regeneration, long-term stability, and real-sample validation are critically assessed. Overall, this review provides analytically driven design principles and identifies emerging directions, such as data-assisted sensing, sustainable fabrication, and smart fibre-based devices, aimed at advancing robust, deployable, and environmentally sustainable monitoring technologies.