Shahid Mohammad, El Saliby Ibrahim, McDonagh Andrew, Chekli Laura, Tijing Leonard D, Kim Jong-Ho, Shon Ho Kyong
J Nanosci Nanotechnol. 2016 May;16(5):4342-9. doi: 10.1166/jnn.2016.10998.
Solar photocatalytic degradation of organic water pollutants can be used to degrade toxic organic pollutants in water. In this study, potassium titanate nanofibres were synthesized by an aqueous peroxide route at high pH and examined as photocatalysts for photodegradation of methylene blue (MB) using a solar simulator. Initially, MB was adsorbed on the surface of potassium polytitanates to achieve adsorption equilibrium before the photocatalysts were illuminated using solar simulator. The results showed that potassium polytitanate nanofibres were effective adsorbents of MB and also facilitated its photocatalytic degradation. Sulphate ion evolution during photocatalysis confirmed that some mineralisation occurred and hence photo-oxidative degradation of MB took place. The optimum operational conditions for the photocatalytic degradation of MB were found at 0.05 g/L of photocatalyst load, 10 mg/L MB and pH 7. The stability and regeneration of the photocatalyst specimen was also studied for 3 degradation cycles using adsorption/photocatalysis model. Morphological structure analysis of potassium titanate showed nanocrystallines structure of longitudinally-oriented isolated fibre with a length up to several micrometres with diameters ranging from 10 to 20 nanometres.
太阳能光催化降解水中有机污染物可用于降解水中的有毒有机污染物。在本研究中，通过在高pH值下的过氧化物水溶液路线合成了钛酸钾纳米纤维，并使用太阳能模拟器将其作为光催化剂用于亚甲基蓝（MB）的光降解。最初，在使用太阳能模拟器照射光催化剂之前，MB被吸附在聚钛酸钾表面以达到吸附平衡。结果表明，聚钛酸钾纳米纤维是MB的有效吸附剂，并且还促进了其光催化降解。光催化过程中硫酸根离子的析出证实发生了一些矿化作用，因此MB发生了光氧化降解。发现MB光催化降解的最佳操作条件为光催化剂负载量0.05 g/L、MB浓度10 mg/L和pH值7。还使用吸附/光催化模型对光催化剂样品进行了3个降解循环的稳定性和再生研究。钛酸钾的形态结构分析表明，其为纵向取向的孤立纤维的纳米晶体结构，长度可达几微米，直径范围为10至20纳米。
