Figure 1From: Surfactant-free synthesis of Cu2O hollow spheres and their wavelength-dependent visible photocatalytic activities using LED lamps as cold light sourcesSEM images and particle size distribution. SEM images of Cu2O hollow spheres obtained at 0°C (a), 25°C (b), and 50°C (c). The insets show the corresponding hollow structures. Diameter distributions of Cu2O hollow spheres prepared at 0°C (d), 25°C (e), and 50°C (f).Back to article page