Piezoelectric device, liquid ejection head, and liquid ejection apparatus

A piezoelectric device comprising:

• an empty chamber component defining an empty chamber;
• and
• a piezoelectric element provided on one side of the empty chamber component with a flexible surface located between the piezoelectric element and the empty chamber, the piezoelectric element including a first electrode, a piezoelectric component, and a second electrode that are stacked in this order from a side where the flexible surface is formed,
• wherein in the empty chamber component, an empty portion independent of the empty chamber is formed at a position where an end of an active section passes through the empty portion in plan view, the active section being an overlapping portion of the first electrode, the piezoelectric component, and the second electrode in plan view.