Ag–TiO2/HAP/Al2O3 bioceramic composite membrane: Fabrication, characterization and bactericidal activity
Ag–TiO2/HAP/Al2O3 bioceramic composite membrane: Fabrication, characterization and bactericidal activity
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DOI：
10.1016/j.memsci.2009.03.018
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发表时间：
2009-07
影响因子：
9.5
通讯作者：
N. Ma;Xinfei Fan;X. Quan;Yaobin Zhang
中科院分区：
文献类型：
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作者：
N. Ma;Xinfei Fan;X. Quan;Yaobin Zhang
采用溶胶-凝胶法和焙烧两步法制备了银-二氧化钛/羟基磷灰石(HAP，Ca10(PO4)6(OH)2)/Al_2O_3生物陶瓷复合膜，实现了膜分离和光催化细菌灭活的一体化。所制备的复合膜为平均孔径为0.8μm的微孔膜结构，由厚度为10μm的Ag-Ti02/HAp复合层组成，覆盖在α-Al_2O_3磁盘支撑体上。Ag-TiO2/HAP复合层的详细形貌显示，部分覆盖在HAP颗粒上的Ag-TiO2光催化层厚度为10-30 nm。表面光伏测试表明，1wt.%Ag-TiO2复合材料具有较强的促进界面电荷转移反应的能力。设计了一种快速错流膜系统，以评价HAP层和Ag-TiO2光催化剂在悬浮液中对大肠杆菌灭活的作用。HAP是一种高效的细菌吸附剂，而Ag-TiO2对大肠杆菌有很强的光催化作用。在紫外光照射(弱光强度为0.3 mW/cm2)和黑暗条件下，所制备的膜在60min内对大肠杆菌的去除效果分别约为6log单位和4log单位。紫外光照射1h后，出口渗透通量较黑暗条件下明显提高71.7%。结果表明，这种新型抗污染膜可以集膜分离、细菌吸附和光催化灭活于一体，在地下水和饮用水的抗菌处理方面具有很大的潜力。
Ag–TiO2/hydroxyapatite (HAP, Ca10(PO4)6(OH)2)/Al2O3bioceramic composite membrane was fabricated to integrate membrane separation and photocatalytic bacterial inactivation by a facile two-step approach involving sol–gel method followed by calcination. The as-prepared composite membrane was characterized as a microporous membrane structure with average 0.8μm pore size, which comprised of Ag–TiO2/HAP composite layer with a thickness of 10μm overlaid on α-Al2O3disk support. Detailed morphology of Ag–TiO2/HAP composite layer revealed a thickness of 10–30nm Ag–TiO2photocatalytic layer partially covered over HAP particles. Surface photovoltage measurement revealed a superior ability of promoted interfacial charge-transfer reactions in the case of 1wt.% Ag–TiO2composite. A rapid crossflow membrane system was designed to evaluate the roles of the HAP layer and Ag–TiO2photocatalyst in the inactivation of Escherichia coli (E. coli) in suspension. HAP acted as a high efficient bacterial adsorbent while Ag–TiO2provided powerful photocatalytic attack toward E. coli strains. The removal of E. coli within 60min with as-prepared membrane was approximately 6 and 4log units under UV illumination (a weak light intensity of 0.3mW/cm2) and in dark, respectively. The permeate flux of outlet was evidently improved by 71.7% after 1h under UV illumination, compared with that in dark. These results showed that this novel membrane of anti-fouling property might integrate multifunction of membrane separation, bacterial adsorption and photocatalytic inactivation, which suggested great potential for antibacterial treatment of groundwater and drinking water.