采用差示扫描量热仪研究了聚(N-异丙基丙烯酰胺)温敏水凝胶负载锌酞菁(GE-ZnPc)的温敏性能,测得其体积相转变温度(VPTT)为34.3℃。以α-萘酚为研究对象,考察了不同温度下GE-ZnPc对α-萘酚的吸附性能,发现该吸附过程符合Freundlich吸附模型。吸附热力学研究结果表明,在VPTT以下是吸热反应,温度升高有利于吸附;在VPTT以上是放热反应,温度升高不利于吸附。另外,还研究了GE-ZnPc对水溶液中α-萘酚的光催化氧化情况,发现其在可见光照射下具有较高的光催化活性,并且考察了温度对GE-ZnPc光催化性能的影响,发现其吸附和光催化活性都是在VPTT附近达到最高,说明吸附作用对其光催化性能的提高起重要作用。
The thermosensitive property of poly(N-isopropylacrylamide) hydrogel supported zinc phthalocyanine(GE-ZnPc) was studied by differential scanning calorimetry,and the volume phase transition temperature(VPTT) was 34.3℃.In this paper,α-naphthol was chosen as the substrate,and the results of adsorption thermodynamics showed that the adsorption process of α-naphthol on GE-ZnPc was in accordance with the Freundlich isotherm model.The adsorption of α-naphthol on GE-ZnPc below VPTT was an endothermic process and the temperature increasing is conductive to adsorption.The adsorption above VPTT was an exothermic process and the temperature increasing is not conductive to adsorption.In addition,the photocatalytic activity of GE-ZnPc for the oxidation of α-naphthol was determined.The result showed that GE-ZnPc exhibited a high photocatalytic activity under the visible light irradiation.The effect of reaction temperature on the adsorption and photocatalytic oxidation was also studied.The result indicated that when the temperature was closed to the VPTT,both adsorption and photocatalytic removal of α-naphthol reached the maximum values.Thus,the adsorption behavior of GE-ZnPc plays an important role in the enhancement of photocatalytic activity.