Photochemistry has developed over the past century in homogeneous systems such as the gas-phase and liquid-phase, and then in crystal solids of organic compounds based on the detection of products as well as the measurements of fluorescence and phosphorescence (photoluminescence, PL).¹⁾ These remarkable developments in photochemistry have been highly evaluated as evidenced by such studies as the flash photolysis by Prof. George Porter and transition states of chemical reactions using femtosecond spectroscopy by Prof. Ahmed H. Zewail who received the Nobel Prize in Chemistry in 1967 and 1999, respectively. During the progress in homogeneous systems, the photochemistry in certain constrained environments such as adsorption on solid surfaces of silica and zeolites has been actively investigated with the aim of controlling reaction paths and yields.²⁾

The object of this webinar lectures No. 3 and 4 is to introduce and explain the fundamental science and technology of heterogeneous photochemistry, that is, photochemical features of the molecules adsorbed on the surfaces of solid materials such as silica and zeolites as compared with the homogeneous photochemistry. In the first part (No. 3) I will introduce the fundamentals of photochemistry and heterogeneous photochemistry of adsorbed molecules on silica and zeolites-based materials. In the second part (No. 4) I will explain the detailed photochemical reaction mechanism of the single-site heterogeneous photocatalysis and some semiconducting photocatalysts at the molecular level based on the PL measurements including their dynamics together with various advanced studies by applying EPR, FT-IR, XAFS methods, etc. ^3-7)　

PL spectroscopy has been applied for the characterization of the surface active sites of the heterogeneous catalysts related to adsorption, catalysis, and photocatalysis. And, much useful information about the energy states and structural character of catalytic material has been reported at the molecular level by monitoring the PL at the working states.^3-7) Nowadays, PL is widely used as one of the fundamental tools to study the local coordination states of bulk catalysts and the active sites of highly dispersed single-site heterogeneous catalysts. It is also widely utilized to study the structural perturbations and the mechanisms of catalysis and photocatalysis on inorganic and organic semiconducting materials due to its higher sensitivity and non-destructive nature.

1) N. J. Turro, “Modern Molecular Photochemistry”, Benjamin/Cumming Publishers. Co., Inc. (1978).

2) M. Anpo and T. Matsuura, “Photochemistry on Solid Surfaces”, Elsevier, (1989).

3) M. Anpo and M. Che, Applications of PL techniques to the characterization of solid surfaces in relation to adsorption, catalysis and photocatalysis, Adv. Catal., 44 (1999) 120-257 and 52 (2009) 1-42.  

4) QH. Li, M. Anpo, XC. Wang, Res. Chem. Intermed., 46 (2020) 4325-4344 (Review).

5) M. Anpo, E. Giamello, Z. Sojka, et al., J. Catal., 393 (2021) 259-280 (invited Review).

6) M. Daniela, M. Anpo, B. Neppolian, et al., Coord. Chem. Rev., 468, 214627 (2022) (Review).

7) Q Zhang, M. Anpo, JL. Zhang, et al., Catal. Letters, (invited Perspective Article, in press) (2022).

报告人简介:

Masakazu Ampo（安保正一）教授是国际著名的光催化学者，被誉为固体表面光化学研究的先驱者。曾担任国际催化理事会理事，也是亚太催化学会的创始人之一，为催化科学和技术的发展做出了重要贡献。2008年成为首个亚洲籍欧洲科学院院士，2011年入选日本科学委员会委员，获2021年度中国政府友谊奖。曾任日本大阪府立大学常务副校长，现担任日本大阪公立大学名誉教授、学院特别荣誉教授、能源与环境光催化创新引智基地海外学术大师。先后出版115本书籍、发表541篇原创论文，累计引用超过3万次。