Chapter 3
Titanium-Based Mesoporous Materials
for Photocatalysis
3.1 The History of Mesoporous Materials
Up to date, it is well known that the rapid progress of society is closely associated
with material science. Particularly in recent 30 or 40 years, there has been a boom of
novel materials, including of mesoporous materials. Mesoporous molecular sieve
belongs to a noticeable area owing to its excellent properties, such as high specific
surface area and adjustable ordered mesoporous pore size. According to the rules of
IUPAC, porous materials can be classified into three types: micropore materials
(pore size <2 nm), mesopore materials (2 nm
successfully synthesized a novel ordered mesoporous silica materials called M41S
with surfactants as templating agents, thus opening a new era of mesoporous
materials [2]. On the basis of chemical composition, mesoporous molecular sieve
can be divided into two categories: silicon-based materials and non-silicon-based
materials. The most common one is M41S, which is a branch of silicon-based
materials. Additionally, there are many other sorts of mesoporous molecular sieves,
such as SBA-n series, MSU series, CMK series, HMS, KIT, and metallic or metal
oxide series. Compared with microporous and macroporous molecular sieves,
mesoporous materials possess many outstanding characteristics. But there are still
some shortcomings exist, for instance, its low hydrothermal stability and weak
acidity, which limit its application. Ryoo et al. [3] synthesized highly stable
MCM-41 by adjusting the pH value of the solution and adding salt compounds.
And Mokaya et al. [4] obtained ultrastable MCM-41 by post-processing. Robert
Mokaya prepared restructured pure silica MCM-41 materials through seeded crystallization route. This method used MCM-41 as “silica source” for secondary
synthesis with extending the reaction time of periods. Therefore, the pore wall
thickness was increased systematically by extending the time. The remarkable
stability is attributed to the combination of thicker pore walls and less strained silica
frameworks.
© Springer Nature Singapore Pte Ltd. 2018
J. Zhang et al., Photocatalysis, Lecture Notes in Chemistry 100,
https://doi.org/10.1007/978-981-13-2113-9_3
47
Titanium-Based Mesoporous Materials
for Photocatalysis
3.1 The History of Mesoporous Materials
Up to date, it is well known that the rapid progress of society is closely associated
with material science. Particularly in recent 30 or 40 years, there has been a boom of
novel materials, including of mesoporous materials. Mesoporous molecular sieve
belongs to a noticeable area owing to its excellent properties, such as high specific
surface area and adjustable ordered mesoporous pore size. According to the rules of
IUPAC, porous materials can be classified into three types: micropore materials
(pore size <2 nm), mesopore materials (2 nm
successfully synthesized a novel ordered mesoporous silica materials called M41S
with surfactants as templating agents, thus opening a new era of mesoporous
materials [2]. On the basis of chemical composition, mesoporous molecular sieve
can be divided into two categories: silicon-based materials and non-silicon-based
materials. The most common one is M41S, which is a branch of silicon-based
materials. Additionally, there are many other sorts of mesoporous molecular sieves,
such as SBA-n series, MSU series, CMK series, HMS, KIT, and metallic or metal
oxide series. Compared with microporous and macroporous molecular sieves,
mesoporous materials possess many outstanding characteristics. But there are still
some shortcomings exist, for instance, its low hydrothermal stability and weak
acidity, which limit its application. Ryoo et al. [3] synthesized highly stable
MCM-41 by adjusting the pH value of the solution and adding salt compounds.
And Mokaya et al. [4] obtained ultrastable MCM-41 by post-processing. Robert
Mokaya prepared restructured pure silica MCM-41 materials through seeded crystallization route. This method used MCM-41 as “silica source” for secondary
synthesis with extending the reaction time of periods. Therefore, the pore wall
thickness was increased systematically by extending the time. The remarkable
stability is attributed to the combination of thicker pore walls and less strained silica
frameworks.
© Springer Nature Singapore Pte Ltd. 2018
J. Zhang et al., Photocatalysis, Lecture Notes in Chemistry 100,
https://doi.org/10.1007/978-981-13-2113-9_3
47