I. Classification by Material

1. Glass Silica Plates: Utilizing smooth and uniform glass as a substrate, with silica evenly coated on the surface. Suitable for general separations such as bioorganic substances, organic compounds, pesticides, etc.

2. Aluminum Silica Plates: Consisting of aluminum foil as a substrate, coated with a uniform layer of silica. Appropriate for separating volatile or thermally sensitive compounds, such as alcohols, phenols, ketones, aldehydes, etc.

3. Polyamide Silica Plates: Employing a polyamide film as a substrate, uniformly coated with silica during the surface condensation process. Suitable for compounds exhibiting strong affinity to organic alcohols, amines, carboxylic acids, etc.

II. Classification by Particle Size

1. Large Pore Silica Plates: Particles with a diameter greater than 10nm, suitable for separating compounds with large molecular weights.

2. Medium Pore Silica Plates: Particles with a diameter and pore size ranging from 2 to 10nm, suitable for separating compounds with moderate molecular weights.

3. Small Pore Silica Plates: Particles with a small diameter, pore size less than 2nm, suitable for separating compounds with small molecular weights.

III. Classification by Coating Method

1. Evenly Coated Silica Plates: Silica uniformly coated on the substrate, suitable for separating polar or moderately polar compounds.

2. Unevenly Coated Silica Plates: Silica coated unevenly on the substrate, suitable for separating large molecular weight compounds.

IV. Classification by Protectant

1. Unprotected Silica Plates: Silica surface without a covering layer, offering high separation capability and sensitivity.

2. Protectant-Coated Silica Plates: Silica surface covered with a protective layer, ensuring a smooth surface and the most stable separation effects but may reduce separation efficiency to some extent.

Different types of silica plates have distinct characteristics and applications. Therefore, the selection and usage should be based on the nature of the substances and the specific field of application.