TiO_2/g-C_3N_4复合物的光催化性能测试及机理研究

TiO_2/g-C_3N_4 composites performed ophotocatalysis and the deduction of enhanced mechanism

利用超声剥离法将块体g-C_3N_4剥离成少层g-C_3N_4,之后与TiO_2进行复合并将所得产物进行二次高温煅烧,得到一种界面间距更小,光生电子传递速率高,光催化性能强的TiO_2/g-C_3N_4的光催化剂。通过XRD,SEM,TEM和FT-IR对其结构进行表征,发现TiO_2是以化学键的形式均匀地附着在少层g-C_3N_4表面;UV-vis和PL分析表明,该催化剂实现了紫外区到可见区的全覆盖吸收,并能有效地抑制光生电子和空穴的复合;降解实验和分解水制氢实验表明TiO_2的负载量为3%时其光催化性能最好,100 min时对罗丹明B的降解率达到87.7%,光催化分解水制氢速率高达68.62μmol h^(-1)。探讨总结了该复合物的光催化机理。

Ultrathin g-C3N4 was exfoliated from bulk g-C 3N 4,composited with TiO 2 and then heated at high temperature for the tightly combination.The transport efficiency and photocatalytic performance of composites were improved.The XRD patterns,SEM images,TEM images and FT-IR spectra revealed that the TiO 2 nanoparticles were deposited on the surface of g-C 3N 4 nanosheets and connected by chemical bond.The UV-vis spectra and PL spectra indicated that the composites can not only enhance the absorption properties in visible light,but also suppress the recombination of charge carriers.The results of RhB degradation and H 2 production rate indicated that the composites had a good performance when the TiO 2 reached to 3%.The degradation rate of RhB and H 2 production rate reached to 87.7%and 68.62μmol h-1,respectively.The enhanced mechanism of this composites was also studied elaborately.