fig2
Figure 2. FTIR differential spectra of Pt/Sn-Al2O3 at 600 °C with different numbers of pulses of propane. (A) 4,000-3,200 cm-1; (B) 3,200-2,700 cm-1; (C) 2,700-1,800 cm-1; (D) 1,800-1,200 cm-1. The pulse experiments were carried out at 600 °C by pulses of pure propane (pulse volume = 0.50 cm3 STP) to the in situ cell, which was maintained under Ar flow (30 mL/min) between two successive pulses. The yellow dashed line represents the adsorption peak, while the white dashed line represents the inverted peak caused by the occupation of the adsorption site. FTIR: Fourier transform infrared spectroscopy; STP: standard temperature and pressure.
