These oxidize the hydrogen to water.  Examples include:
* Nitric acid, used in the Grove cell and Bunsen cell
* Chromic acid, used in the Chromic acid cell
* Manganese dioxide, used in the Leclanché cell and Dry cell
Nitric and chromic acids are powerful oxidizing agents, and effective depolarizers, but their hazardous nature makes them unsuitable for general use.  Manganese dioxide is, therefore, the most widely used depolarizer.