摘要
以水杨酸(SA)为模板分子,钛酸四丁酯为钛源,硝酸钕为掺杂剂,采用溶胶-凝胶法,在不同焙烧温度和不同Nd掺杂量下制备了一系列Nd掺杂分子印迹TiO_2(NMT)光催化剂。采用XRD、SEM、TEM、ICP-AES、EDS、XPS、FT-IR、N_2吸附-脱附(BET模型)、紫外-可见漫反射光谱(UV-Vis DRS)等手段对产物进行了表征,并以光催化降解SA为指针反应,考察了Nd掺杂量、焙烧温度、SA溶液初始pH值对产物光催化活性的影响。结果表明,NMT为单一锐钛矿相,孔道结构的形成是晶粒堆积孔和模板剂脱除所致。相比非印迹TiO_2和未掺杂的分子印迹TiO_2,NMT对模板分子降解反应的光催化活性大大提高,且当n(Nd)∶n(TiO_2)=0.30%、550℃热处理2 h时光催化活性最佳:紫外光下其作为光催化剂可以得到86.4%的降解率(SA模拟废水初始浓度为20 mg/L、初始pH=4,降解反应时间为70 min),重复使用四次降解率仍保持在83.02%;可见光(λ>400 nm)下可以得到97.96%的降解率(SA模拟废水初始浓度为20 mg/L、初始pH=4,降解反应时间为30 h)。
This contribution presents the fabrication,characterization and photocatalytic performance evaluation of neodymium-doped molecularly imprinted titanium dioxide(NMT)which is expected to serve as photocatalysts for organic compounds degradation in aqueous solution.We prepared a series of NMT samples via a sol-gel process,which differed in calcination temperature and Nd doping amount,by using salicylic acid(SA)as template,tetrabutyl titanate as titanium source and neodymium nitrate as dopant.The characterization of the resultant samples was carried out by means of XRD,SEM,TEM,ICP-AES,EDS,XPS,FT-IR,N2 adsorption-desorption(BET model)and UV-Vis DRS.Moreover,we investigated the photocatalytic activities of the products toward the template molecules(SA),under both UV and visible light irradiations,and with various calcination temperatures,various Nd doping amounts,and various initial pH values of SA solution.The experimental results confirmed the single anatase phase composition of NMT,and a highly porous structure induced by accumulation of grain clusters and template removal.All the NMT samples displayed the photocatalytic activities much higher than those of undoped molecularly imprinted TiO2 and ordinary(non-imprinted)TiO2 for the degradation reaction of the template molecule(SA).The NMT sample with molar ratio of Nd/TiO2 of 0.30%and calcination tempe-rature of 550℃exhibited the highest photocatalytic activity,as it could achieve a 86.4%(within 70 min)degradation rate and a 97.96%(within 30 h)degradation rate for SA aqueous solution(initial concentration 20 mg/L,initial Ph=4),under UV and visible irradiations,respectively.In addition,the degradation rate could remain above 83.02%within 4 times of reuse under UV irradiation.
作者
占昌朝
曹小华
金文雄
叶志刚
谢宝华
徐建兴
周荣辉
ZHAN Changchao;CAO Xiaohua;JIN Wenxiong;YE Zhigang;XIE Baohua;XU Jianxing;ZHOU Ronghui(College of Chemistry and Environmental Engineering,Jiujiang University,Jiujiang 332005;Jiangxi Province Engineering Research Center of Ecological Chemical Industry,Jiujiang 332005)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2019年第6期947-953,共7页
Materials Reports
基金
国家自然科学基金(51562016
21864015)
江西省自然科学基金(20171BAB206015)
九江学院科技基金(2016KJ005)~~
关键词
分子印迹
钕(Ⅲ)
二氧化钛
水杨酸
模板分子
光催化
溶胶-凝胶法
紫外光
可见光
molecular imprinting
neodymium(Ⅲ)
titanium dioxide
salicylic acid
template molecule
photocatalysis
sol-gel method
ultraviolet light
visible light
