Fluorescence‐Suppressed Mapping of Representative Soils Enabled by Time‐Gated Raman Spectroscopy

ABSTRACT Raman spectroscopy provides a nondestructive method for mineral characterization, but its use in soils is often restricted by strong fluorescence and compositional heterogeneity. Here, five representative soils (black, red, yellow, blue, and purple) were systematically examined using a self‐developed time‐gated Raman (TGR) spectroscopy system, which effectively suppressed fluorescence and enabled high‐quality Raman spectra from all soils. Key mineral components—including quartz, feldspar, hematite, montmorillonite, garnet, anatase, and calcite—were clearly identified and semiquantitatively evaluated through relative peak areas. Spatially resolved Raman mapping further revealed micrometer‐scale heterogeneity in mineral distribution, providing insights into both abundance and spatial uniformity. Overall, TGR demonstrated significant advantages over conventional Raman approaches in analyzing fluorescence‐rich and heterogeneous soils. Its capability for fluorescence‐free, high‐resolution, and spatially resolved mineral analysis highlights the potential of TGR as a versatile tool for soil science and other fields where conventional Raman spectroscopy remains limited.