氟氮共掺杂二氧化钛/还原氧化石墨稀复合光催化剂的制备及其可见光催化性能

Synthesis of F, N Co-doped TiO_2 Decorated Reduced Graphene Oxide and Its Visible Light Photocatalytic Properties

以氧化石墨烯（GO）、TiO2、尿素、NH4F 和 Vc 为原料，采用水热法制备氟氮共掺杂二氧化钛/还原氧化石墨烯复合光催化剂（F-N-TiO2/rGO）。对制备的 F-N-TiO2/rGO 样品的相组成、结构、形貌和光谱性质进行分析表征。结果表明：F、N共掺杂的 TiO2仍为锐钛矿晶型，呈纳米颗粒状均匀分布在片状还原氧化石墨烯表面；增强了对400~800 nm 可见光的吸收，且吸收边发生明显的红移；同时 C—Ti 共价键的形成使石墨烯与 TiO2紧密结合，提高了界面电荷传输效率使光生电子有效分离，使得 F-N-TiO2/rGO 的催化活性大大增强，可见光下对甲基橙（MO）的降解速率达1.17 mg/（h·g），是商品 P25的2.8倍。

F and N co-doped TiO2 decorated graphene oxide composite photocatalysts （F-N-TiO2/rGO） were prepared with the graphene oxide （GO）, TiO2, urea, NH4F and Vc as precursors by a one-step hydrothermal method. The composition, structure, morphology and spectral properties of the composite photocatalyst were investigated. The results show that F and N co-doped TiO2 particles with anatase phase are well-dispersed on the surface of the reduced graphene oxide （rGO） sheets. The absorption edge of F-N-TiO2/rGO shifts to the visible light range and the optical absorption shows an enhancement in the visible light region from 400 nm to 800 nm. The degradation rate of methyl orange on F-N-TiO2/rGO composite is 1.17 mg/（h·g） under visible light, which increases 2.8 times greater than that on commercial P25. This is attributed to the interaction between TiO2 and graphene via C-Ti covalent bonds, which promotes the efficient separation of photogenerated charges resulting from the improved electrical conductivity of the rGO sheets.