Tantalum capacitors are electrolytic capacitors that use tantalum material to form the anode. They are polarized devices, relying on a thin oxide layer formed on the tantalum anode to serve as the dielectric. A typical tantalum capacitor consists of a tantalum powder anode, a dielectric layer of tantalum pentoxide (Ta₂O₅), and a cathode made from either manganese dioxide (MnO₂) or a solid conductive polymer.

As passive electronic components, capacitors store electric charge. In tantalum capacitors, the anode is made of tantalum metal (+), the cathode is the electrolyte, and the dielectric is the thin tantalum oxide layer. These capacitors offer a high capacitance-to-volume ratio (CV product) with low weight, making them highly reliable and widely used in applications where performance and durability are critical.