Theoretical investigation of structural, electronic and mechanical properties of PbO₂ under pressure

PbO 2 has significant application value in energy storage and catalysis fields, and the pressure response mechanism of its crystal structure and physical properties is a key issue in material design. This paper uses first-principles calculations based on density functional theory (DFT) to systematically study the crystal structure, electronic properties, and mechanical behavior of [Formula: see text]-PbO 2 and [Formula: see text]-PbO 2 within the pressure range of 0–30[Formula: see text]GPa, including lattice parameters, bulk modulus, Young’s modulus and shear modulus. The results show that [Formula: see text]-PbO 2 remains mechanically stable within this pressure range, while the bulk modulus of [Formula: see text]-PbO 2 is higher than that of the [Formula: see text]-PbO 2 , but it becomes unstable when exceeding 10.99 GPa due to C[Formula: see text]-[Formula: see text]. Population analysis reveals that [Formula: see text]-PbO 2 and [Formula: see text]-PbO 2 have significant covalent characteristics, with obvious hybridization phenomena between O 2p, Pb 6s and Pb 6p states. The pressure enhances the covalency of the Pb–O bond. This study provides theoretical support for the design of PbO 2 based materials under high pressure and the optimization of the positive electrode materials of lead-acid batteries.