Fig. 2From: Facile Synthesis and High Photocatalytic Degradation Performance of ZnO-SnO2 Hollow SpheresSEM images of carbon spheres (a), ZnO-SnO2 hollow spheres (c), and ZnO hollow spheres (e). TEM image of carbon spheres (b), ZnO-SnO2 hollow spheres (d), and ZnO hollow spheres (f)Back to article page