TiO 2 sensitized by red-, green-, blue-emissive carbon dots for enhanced H 2 production

Carbon dots (Cdots) with a broad light absorption range could be a potential stable sensitizer for TiO 2 , which is an excellent ultraviolet (UV) response photocatalyst. Herein, we systematically investigated the different color emissive Cdots-sensitized TiO 2 for H 2 production. Firstly, all kinds of Cdots enhanced the photocatalytic properties of TiO 2 . All the Cdots-sensitized TiO 2 exhibits visible light H 2 production due to their absorption in the visible light region. The photocurrent and H 2 production amount display strong dependence on the light absorption range of Cdots. The blue-emissive Cdots endow the weak H 2 production rate due to its weak absorption in the visible light. The enhanced photocatalytic activities are mainly contributed to the strong light absorbance and high-efficient charge separation. The light absorption of green- and red-emissive Cdots is another main factor for the high catalytic activities besides charge separation. Graphical abstract