Figure 2. XPS wide-scan spectra of SiO₂ decontaminated with 5% sodium peroxodisulfate solution and acetone, then treated with -MPTS, followed by ultrasonic rinsing twice in ultrapure water for 5 min in (a), SiO₂ decontaminated with 5% sodium peroxodisulfate solution and acetone, then treated with TTDCS, followed by ultrasonic rinsing twice in chloroform for 5 min in (b), and SiO₂ treated with TTDCS without pre-silanization decontamination in (c).