Fluorescent copper nanoclusters: Synthesis strategies and applications in visual detection of environmental pollutants

Fluorescent visualization detection has emerged as a powerful strategy for rapid on-site monitoring of environmental pollutants, owing to its simplicity, low cost, and easily distinguishable naked-eye signal output. Among various fluorescent nanomaterials, metal nanoclusters (MNCs) have recently attracted considerable attention as promising candidates for developing naked-eye-visible probes, owing to their structural diversity and tunable properties. In particular, copper nanoclusters (CuNCs) not only exhibit adjustable structural and photophysical characteristics but also offer advantages such as lower cost and higher environmental compatibility compared with precious metal nanoclusters. In this review, we summarize recent advances in the synthesis, structural design, and performance optimization of CuNCs-based fluorescent probes. Particular emphasis is placed on their visualization sensing mechanisms, detection strategies, and practical applications in environmental pollutant monitoring, with a focus on studies reported in the past 5 years. Overall, this review provides both theoretical insights and practical guidance for developing CuNCs-based visualization detection methods, strategies, and applications, with significant implications for enhancing the efficiency and convenience of pollutant monitoring and promoting pollution prevention and control.