Design and development of photocatalysts of high activity and highly efficient photocatalytic reaction systems based on the understanding of photocatalytic reaction mechanisms

1.作用谱分析：结果表明，这是最好的方法之一，用于评价光催化剂和光催化反应，显示亚甲基蓝，一个经常使用的光催化反应底物，分解通过光敏化机制，以及光催化反应。此外，用光学截止滤光片得到的伪作用谱与真实作用谱的形状不同.通过新型气相反应制备高活性二氧化钛光催化剂：金属氧化物颗粒的高温气相合成是有利的，因为促进了颗粒的结晶而没有聚集以得到更大的颗粒。在这项研究中，新型的二氧化钛制备方法，使快速加热-快速冷却的氯化钛（IV）的开发。结果表明，该纳米晶具有十面体结构，暴露出101和001两种晶面，在多种反应体系中均表现出较高的光催化活性。优化了制备条件.从Degussa P25中分离金红石和金红石微晶：从Degussa P25中，通过新开发的方法分离具有金红石和金红石混合微晶的代表性商业二氧化钛粉末，金红石和金红石微晶。分离的样品用于制作每个晶相的校准曲线，以首次获得P25的确切组成，并用于从两种分离的纯微晶和商业无定形二氧化钛中重建P25。通过比较改性前后样品的物理性能和光催化活性发现，金红石和金红石的混合对样品的光催化活性没有明显的协同作用。

1. Action spectrum analyses: It was revealed that this is one of the best methods for the evaluation of photocatalysts and photocatalytic reaction by showing that methylene blue, a frequently employed photocatalytic reaction substrate, is decomposed through photosensitizing mechanism as well as photocatalytic reaction. Moreover, pseudo action spectra taken by using optical cut-off filters show different shape compared from true action spectra.2. Preparation of highly active titania photocatalyst through novel gas phase reaction: High temperature as-phase synthesis of metal oxide particles is favorable since crystallization of particles is promoted without aggregation to give larger particles. In this study, new type of titania preparation method enabling rapid heating-rapid cooling of titanium(IV) chloride was developed. The resulting anatase small crystallites were of decahedral shape exposing two kinds of lattice facet, 101 and 001 and showed high photocatalytic activity in several reaction systems. The preparation conditions were optimized.3. Isolation of anatase and rutile crystallites from Degussa P25: From Degussa P25, a representative commercial titania powder with anatase and rutile mixed crystallites, anatase and rutile crystallites were isolated through newly developed method. The isolated samples were used for making calibration curves of each crystal phase to obtain, for the first time, exact composition of P25 and for reconstruction of P25 from two kinds of isolated pure crystallites and commercial amorphous titania. Comparison of physical properties and photocatalytic activities between original and reconstructed samples revealed that there seems to be no synergetic effects by mixing anatase and rutile on the photocatalytic activity.