State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 3888 East Nanhu Road, Changchun, Jilin 130033, P. R. China.
Nanoscale. 2013 Dec 21;5(24):12272-7. doi: 10.1039/c3nr04402e.
A facile hydrothermal synthesis route to N and S, N co-doped graphene quantum dots (GQDs) was developed by using citric acid as the C source and urea or thiourea as N and S sources. Both N and S, N doped GQDs showed high quantum yield (78% and 71%), excitation independent under excitation of 340-400 nm and single exponential decay under UV excitation. A broad absorption band in the visible region appeared in S, N co-doped GQDs due to doping with sulfur, which alters the surface state of GQDs. However, S, N co-doped GQDs show different color emission under excitation of 420-520 nm due to their absorption in the visible region. The excellent photocatalytic performance of the S, N co-doped GQD/TiO2 composites was demonstrated by degradation of rhodamine B under visible light. The apparent rate of S, N:GQD/TiO2 is 3 and 10 times higher than that of N:GQD/TiO2 and P25 TiO2 under visible light irradiation, respectively.
一种简便的水热合成路线，通过使用柠檬酸作为 C 源，尿素或硫脲作为 N 和 S 源，合成 N 和 S，N 共掺杂石墨烯量子点（GQDs）。N 和 S，N 掺杂的 GQDs 表现出高量子产率（78%和 71%），在 340-400nm 的激发下具有激发独立性，在紫外光激发下具有单指数衰减。由于掺杂硫，S，N 共掺杂 GQDs 中出现了可见区域的宽吸收带，这改变了 GQDs 的表面状态。然而，由于 S，N 共掺杂 GQDs 在 420-520nm 的激发下吸收可见光，因此显示出不同的颜色发射。通过罗丹明 B 在可见光下的降解，证明了 S，N 共掺杂 GQD/TiO2 复合材料具有优异的光催化性能。在可见光照射下，S，N：GQD/TiO2 的表观速率分别比 N：GQD/TiO2 和 P25 TiO2 高 3 倍和 10 倍。
