Metal-free graphitic carbon nitride (g-CN) has attracted significant attention recently due to its multiple applications, such as photocatalysis, energy storage and conversion, and biomaterials, albeit formation of g-CN films is challenging. Herein, a "grafting to" route to graft polymer brushes onto g-CN via visible-light irradiation is described. Afterward, g-CN/polymer films can be obtained through spin coating on glass substrates. As such, the present material provides an improved process toward further application of g-CN in thin films. Moreover, an improved dispersibility in organic solvent was realized after grafting and functional groups (such as epoxides) were introduced to g-CN. Subsequently, the epoxy groups were utilized for further functionalization to adjust the surface polarity.