Surface‐enhanced Raman spectra of thiourea in acidic solutions

Abstract
Surface‐enhanced Raman scattering (SERS) of thiourea [SC(NH2)2] was studied in acidic solutions of 0.1 M H2SO4 and 0.1 M HCl. Very strong SERS bands of thiourea were observed in the acidic solutions, in contrast to very weak SERS spectra of thiourea in standard SERS solutions employing K2SO4 or KCl. Thiourea seems to have a strong and stable surface adsorption at a silver electrode in the acidic solutions where protonation and anionic co‐adsorption may enhance this surface stability of thiourea.