Study of charge transfer contribution in Surface-Enhanced Raman scattering (SERS) based on indium oxide nanoparticle substrates

Surface-enhanced Raman scattering (SERS) has outstanding merits in biochemical molecular analysis, and the development of new SERS substrates is the focus of research. Herein, In 2 O 3 nanoparticles (NPs) were synthesized by a high temperature pyrolysis method with cubic phase and small particle size at 10 nm. The structures and properties of In 2 O 3 NPs were characterized by X–ray powder diffraction (XRD), transmission electron microscope (TEM) and other characterization methods. Additionally, the SERS spectra of In 2 O 3 -MBA with the enhancement factor ( EF ) up to 1.22 × 10 4 is discussed. The results demonstrate that there is a charge transfer (CT) effect revealed between the adsorbed molecules of 4-mercaptobenzoic acid (4-MBA) and the substrates of In 2 O 3 NPs, and it could be excited by long wavelength energy. Based on the In 2 O 3 NPs, the study is beneficial to develop more potential semiconductor SERS substrates.