Smartphone readable colorimetry and surface-enhanced raman scattering (SERS) dual-mode sensing platform for ascorbic acid detection based on GeO2 composite nanozymes

A self-calibrating flexible SERS substrate incorporating PB@Au assemblies for reliable and reproducible detection

“…3(d) shows two peaks at 88.6 and 84.9 eV, corresponding to Au 4f 5/2 and Au 4f 7/2 , respectively, indicating the zero-valence state of metallic Au. 46 As shown in Fig. 3(e), the peaks at 723.8 and 713.3 eV belonged to the signals of Fe 2p 1/2 and Fe 2p 3/2 , characteristic of Fe( iii ), while the peak at 708.2 eV corresponded to the Fe( ii ) signal, indicating the presence of PB.…”

“…3(c) was deconvoluted into three peaks with binding energies of 405.6, 401.9, and 397.8 eV, which were ascribed to NO, C–N and CN, respectively. 46 The Au 4f spectrum displayed in Fig. 3(d) shows two peaks at 88.6 and 84.9 eV, corresponding to Au 4f 5/2 and Au 4f 7/2 , respectively, indicating the zero-valence state of metallic Au.…”