Transforming Paper into Plasmonic Sensors: One‐Step Fabrication of High‐Enhancement SERS Nanosubstrates via Surface Energy Control
Farbod Ebrahimi, Anjali Kumari, Kyle Nowlin, Tohid Didar, Kristen DellingerABSTRACT
Surface‐enhanced Raman scattering (SERS) substrates require precise control of plasmonic nanoparticles to generate hot spots for ultrasensitive detection. We present the Surface‐Induced Layered Vapor Energy Refined Enhanced Deposition (SILVERED) method for fabricating silver nanoparticle‐decorated paper substrates through single‐step physical vapor deposition on fluorosilanized cellulose. The extreme surface energy differential drives Volmer‐Weber growth, yielding monodisperse (29 ± 4 nm) nanoparticles with high uniformity (PDI = 0.13). Optimal deposition achieved 10 6 enhancement factor and 2 pM detection limit for rhodamine B. The hydrophobic surface enabled analyte pre‐concentration while maintaining reproducibility (RSD < 10%), and the analytical metrics include contributions from substrates drawn across independent fabrication batches. Substrates retained more than 95% of their performance under nitrogen storage. The method's scalability (12‐inch substrates), reproducibility, hydrophobicity, silver nanoparticle size, and low cost position it for diverse applications beyond SERS.