Chapter 6
Inorganic Gels
Abstract This chapter focuses on the discussion of various inorganic gels
including the formation mechanism, molecular systems and functional properties.
The inorganic gels include silica-based gels, chalcogels and others. In the first
section of the chapter, the concept of sol–gel process, which is a commonly used
principle to explain the formation of inorganic gels, is introduced. In the following
sections, three catalogues of inorganic gels are discussed in detail. For silica-based
gels, the nanoparticles of silica derivatives are used as silica sources. The growth
mechanism of silica gels from the nanoparticles and the key factors to determine the
formation process are reviewed. Several representative silica gel systems are presented to show the versatility of the materials. In the following section, chalcogels
are discussed and discussions focus on the preparation methods and catalytic performance of chalcogels. At last, a brief description about other gels including
AgVO 3 and V 2 O 5 gels is given.
Keywords Inorganic gels Á Sol–gel process Á Silica-based gels
Chalcogels
The existence of inorganic gels dates back to 1846 when French chemist Ebelmen
discovered the formation of gels by mixing SiCl 4 with ethanol under wet air
atmosphere [1]. Since the large-scale manufacture of silica gels first started in
1800s, inorganic gels have attracted significant research interests [2]. Apart from
silica gels, Foerster made a jelly-like cupric oxide material by the hydrolysis of a
concentrated solution of cupric ammonium acetate dated back to 1892 [3]. The
observation of the cupric oxide jelly later embarked extended investigations on the
formation of inorganic jellies with other saturated salt solutions [4]. Following the
observation of a wide range of gel materials, the underlying fundamental knowledge, properties and applications have been gradually revealed. The advances in
inorganic gel research significantly contributed to the fabrication of oxide materials
using sol–gel method [5].
Ya Hu and Jianyong Zhang contributed together to this chapter.
© Springer Nature Singapore Pte Ltd. 2018
J. Zhang et al., Gel Chemistry, Lecture Notes in Chemistry 96,
https://doi.org/10.1007/978-981-10-6881-2_6
191
Inorganic Gels
Abstract This chapter focuses on the discussion of various inorganic gels
including the formation mechanism, molecular systems and functional properties.
The inorganic gels include silica-based gels, chalcogels and others. In the first
section of the chapter, the concept of sol–gel process, which is a commonly used
principle to explain the formation of inorganic gels, is introduced. In the following
sections, three catalogues of inorganic gels are discussed in detail. For silica-based
gels, the nanoparticles of silica derivatives are used as silica sources. The growth
mechanism of silica gels from the nanoparticles and the key factors to determine the
formation process are reviewed. Several representative silica gel systems are presented to show the versatility of the materials. In the following section, chalcogels
are discussed and discussions focus on the preparation methods and catalytic performance of chalcogels. At last, a brief description about other gels including
AgVO 3 and V 2 O 5 gels is given.
Keywords Inorganic gels Á Sol–gel process Á Silica-based gels
Chalcogels
The existence of inorganic gels dates back to 1846 when French chemist Ebelmen
discovered the formation of gels by mixing SiCl 4 with ethanol under wet air
atmosphere [1]. Since the large-scale manufacture of silica gels first started in
1800s, inorganic gels have attracted significant research interests [2]. Apart from
silica gels, Foerster made a jelly-like cupric oxide material by the hydrolysis of a
concentrated solution of cupric ammonium acetate dated back to 1892 [3]. The
observation of the cupric oxide jelly later embarked extended investigations on the
formation of inorganic jellies with other saturated salt solutions [4]. Following the
observation of a wide range of gel materials, the underlying fundamental knowledge, properties and applications have been gradually revealed. The advances in
inorganic gel research significantly contributed to the fabrication of oxide materials
using sol–gel method [5].
Ya Hu and Jianyong Zhang contributed together to this chapter.
© Springer Nature Singapore Pte Ltd. 2018
J. Zhang et al., Gel Chemistry, Lecture Notes in Chemistry 96,
https://doi.org/10.1007/978-981-10-6881-2_6
191