响应面法优化N掺杂P25改性材料的制备工艺

Optimization of preparation process for N-doping P25 modified materials by response surface methodology

采用响应面法对N掺杂改性光催化材料N-P25进行优化,提高其在可见光下的光催化活性。以亚甲基蓝作为目标降解物,对煅烧温度、煅烧时间、掺杂量3个因素进行单因素实验。根据单因素实验结果设计中心组合实验,采用响应面分析法确定最优条件。结果表明:煅烧温度为423℃,煅烧时间为2.6h,掺杂量为31%(与P25的质量比)时,NP25可见光催化活性最高,对亚甲基蓝的降解率达到62.21%,与预期值62.94%基本符合。

Response surface methodology was used to optimize the conditions for N-doped P25 photocatalyst＇ s preparation in order to improve the photocatalytic activity which was measured by photocatalytic degradation of methylene blue. The effects of calcination temperature, calcination time and doping amount were studied in single factor experiments. A regression model for the degradation of methylene blue was established using a central composite design which involved the above three factors at three levels. Based on this model, response surface analysis was used to find out the optimum levels of these three factors. The results suggested that the optimum conditions were calcination temperature of 423℃, calcination time of 2.6h and doping amount of 31%. Under these optimum conditions, the photocatalytic activity of N-P25 was the maximum. The degradation of methylene blue reached up to 62. 21 %, which was basically consistent with the predicted val- ue of 24. 41