纳秒脉冲激光/纳米金悬浮体系催化降解2,4,5-TCP

以脉冲激光为光源、纳米金为催化剂,对2,4,5-三氯苯酚(2,4,5-TCP)进行了光催化降解研究,测定了其反应动力学参数,确定了该降解体系中2,4,5-三氯苯酚的单位能量降解率和平均反应速率.EDX能谱和透射电镜表征结果表明,已成功制备了纳米金颗粒,形态主要呈球状,粒径分布均匀,大小在15~20 nm之间.以亚甲基蓝为底物对纳米金的光催化性能进行了表征,结果表明,所制备的纳米金具有较好的催化性能,添加纳米金组比对照组的亚甲基蓝脱色率增加了约15.7%.以2,4,5-TCP为底物时,脉冲激光照射40 min,最高催化降解率约为85%,单位能量降解率为0.18256%·J-1,平均反应速率为0.04667 min-1,反应符合准一级动力学方程ln(C0/Ct)=-0.1141+0.04667t.

Catalytic degradation of 2,4,5-trichlorophenol in aqueous suspensions of gold nanoparticles using nanosecond pulsed laser

Using 266 nm nanosecond pulsed laser, the degradation of 2,4,5-trichlorophenol in aqueous suspensions of gold nanoparticles (GNs) was studied. The photocatalytic degradation dynamics of 2,4,5-trichlorophenol irradiated by nanosecond pulsed laser were modeled. The degradation rate per unit energy and the average reaction rate were also investigated. The energy-dispersive X-ray spectroscopy and transmission electron microscopy results show that GNs were successfully prepared. The prepared GNs were mainly spherical, having a uniform particle-size distribution between 15~20 nm. The photocatalytic ability of GNs was characterized using methylene blue as substrate. The prepared GNs showed good catalytic performance. The decolorization rate has increased by about 15.7% by the addition of GNs. When 2,4,5-trichlorophenol was used as substrate, the highest degradation rate of 85% was reached after reacting for 40 minutes. Besides, the degradation rate per unit energy and the average reaction rate were 0.18256%·J^-1 and 0.04667 min^-1,respectively.Furthermore, the degradation processes of 2,4,5-trichlorophenol followed pseudo-first order kinetics.