The discovery of room-temperature superconductors has aroused great attention in pressure-induced superhydrides. Herein we explore the doping effects on the newly proposed penta-graphene-like hydrides ${\mathrm{ZrH}}_{10}$ and ${\mathrm{HfH}}_{10}$ from first-principles calculations. Imaginary phonon frequencies of $P{6}_3/mmc{\mathrm{ZrH}}_{10}$ and ${\mathrm{HfH}}_{10}$ at lower pressures are found to be eliminated by hole doping, leading to more accessible superconductivity. At high pressures, phonons are prone to be softened by electron doping, which increases the electron-phonon coupling and the superconducting critical temperature ($T_c$). Doping is found to be an effective way to lower the stabilization pressure and increase the $T_c$ of $P{6}_3/mmc{\mathrm{ZrH}}_{10}$ and ${\mathrm{HfH}}_{10}$. This work paves an avenue for realizing low-pressure high-$T_c$ superconducting hydrides.

• Received 1 March 2022
• Revised 27 June 2022
• Accepted 11 July 2022

DOI:https://doi.org/10.1103/PhysRevB.106.024515