Department of Earth Sciences, Waseda University, 1-6-1 Nishiwaseda, Shinjyuku-ku, Tokyo 169-8050, Japan.
J Am Chem Soc. 2010 Mar 17;132(10):3601-4. doi: 10.1021/ja910591v.
The composition of layered alkali titanates (M(x)Ti(2-x/3)Li(x/3)O(4); M = K(+), Li(+), Na(+)) was tuned to control the swelling of the titanates in water and subsequently achieve molecular-sieve-like molecular recognitive photocatalytic decomposition of aqueous organic compounds on the titanates. Layered potassium lithium titanates with different layer charge density, K(x)Ti(2-x/3)Li(x/3)O(4) (x = 0.61, 0.67, and 0.74), was first synthesized and then the interlayer K(+) was quantitatively exchanged with Li(+) and Na(+) to form Li(x)Ti(2-x/3)Li(x/3)O(4) (x = 0.61, 0.67, and 0.76) and Na(x)Ti(2-x/3)Li(x/3)O(4) (x = 0.61, 0.67, and 0.76). The water adsorption/desorption isotherms and X-ray diffraction patterns of the titanates revealed that the pristine K(+)-type titanates hardly hydrated, while the Li(+)- and Na(+)-exchanged titanates expanded the interlayer space upon the hydration and the degree in the hydration was larger for the Na forms than for the Li ones and depended on the layer charge density. The present titanates were found to selectively adsorb benzene from an aqueous mixture of benzene, phenol, and 4-butylphenol and subsequently decompose benzene upon UV irradiation. The efficiency of the molecular recognitive photocatalytic benzene decomposition was related to the degree in the swelling of the titanates in water.
层状碱金属钛酸盐（M(x)Ti(2-x/3)Li(x/3)O(4)；M = K(+)，Li(+)，Na(+)）的组成被调谐以控制钛酸盐在水中的溶胀，从而在钛酸盐上实现水相有机化合物的分子筛状分子识别光催化分解。具有不同层电荷密度的层状钾锂钛酸盐，K(x)Ti(2-x/3)Li(x/3)O(4（x = 0.61、0.67 和 0.74），首先被合成，然后将层间 K(+)定量交换为 Li(+)和 Na(+)，形成 Li(x)Ti(2-x/3)Li(x/3)O(4（x = 0.61、0.67 和 0.76）和 Na(x)Ti(2-x/3)Li(x/3)O(4（x = 0.61、0.67 和 0.76）。钛酸盐的水吸附/解吸等温线和 X 射线衍射图案表明，原始的 K(+)型钛酸盐几乎不水合，而 Li(+)和 Na(+)交换的钛酸盐在水合时扩展了层间空间，并且水合程度对于 Na 形式大于 Li 形式，并且取决于层电荷密度。发现本钛酸盐选择性地从苯、苯酚和 4-丁基苯酚的水混合物中吸附苯，并在紫外线照射下分解苯。分子识别光催化苯分解的效率与钛酸盐在水中溶胀的程度有关。
