Platinum-carbon, also known as platinum-carbon or platinum catalyst, belongs to a type of precious metal catalyst. Its appearance is black powder, with a molecular weight of 195.08 and a molecular formula of PT/C. Platinum-carbon catalysts are carrier catalysts that load platinum onto activated carbon. They are mainly used in chemical reactions such as hydrogen oxidation, methanol oxidation, formic acid oxidation, and oxygen reduction in fuel cells, and are a very common type of precious metal catalyst.
There are many methods for preparing chemical catalyst companies' platinum-carbon catalysts, such as the ion exchange method, impregnation method, and colloid method. Among them, the impregnation method has become one of the effective catalyst preparation methods due to its simple process and easy control. The general process of this preparation method is as follows: Take a certain amount of platinum precursor and mix it into a solution. While stirring, add the carbon carrier that has been moistened in a mixture of isopropanol and water. Adjust the pH value to alkaline, stir for a certain period of time, then filter, and subsequently dry under vacuum at a certain temperature. Drop in an excess amount of reducing agent to activate and obtain the finished catalyst product.
The surface of chemical catalyst companies' platinum-carbon contains various types of structural defects of different degrees. The carbon atoms at the defect sites are more active and can combine with functional groups such as hydroxyl, phenolic, and quinone groups. These surface groups can exchange ions with the ions in the solution in an appropriate medium. The ion exchange method is conducive to the preparation of highly dispersed electrocatalysts due to this characteristic.
The colloid method mainly involves preparing a relatively stable metal oxide colloid first, then transferring it onto the carrier through sedimentation, and then undergoing other processes to obtain it. The advantage of this method is that it can prepare chemical catalyst companies' platinum-carbon catalysts almost free of chlorine from chlorinated precious metal salts, but the process is complex, difficult to control, and the metal particle size range of the catalyst is relatively wide.