Fig. 3. XPS of Si 2p, Cl 2p, and Cu 2p of the bulk Si, bulk CuCl, reacted CuCl/Si, and chlorinated CuCl/Si samples. Reaction conditions: CuCl/Si weight ratio of 8 : 100, 40 g; methanol flow rate, 6 mL h⁻¹. The mixture reacted at 240 °C for 12 h, denoted as reacted CuCl/Si. After reacting for 12 h, the mixture was chlorinated with HCl (40 mL min⁻¹) at 280 °C for 1.5 h, denoted as chlorinated CuCl/Si.