Monochromatic visible light-driven photocatalysis realized on 2D ZnO shell arrays

Using sunlight to solve energy shortage and pollution problems is still a hot but challenging issue. Because of this, we have demonstrated a novel and simple approach to fabricating a 2D shell array structure to enhance the interaction between incident light and the material. The enhancement remarkably increased the two-photon excitation efficiency of the material and, utilizing the two-photon induced electron–hole pairs in ZnO, we realized photocatalysis under monochromatic visible light for the first time. The method and theory described in this paper provide the basis for realizing high-efficiency sunlight-driven photocatalysts and also show a new way to improve the performance of photoelectric and photonic devices.