  Hydrogen and hydrides materials have long been considered promising materials
for high-temperature superconductivity. But the extreme pressures required for
the metallization of hydrogen-based superconductors limit their applications.
Here, we have designed a series of high-temperature perovskite hydrides that
can be stable within 10 GPa. Our research covered 182 ternary systems and
ultimately determined that 9 compounds were stable within 20 GPa, of which 5
exhibited superconducting transition temperatures exceeding 120 K within 10
GPa. Excitingly, KGaH3 and CsInH3 are thermodynamically stable at 50 GPa. Among
these perovskite hydrides, alkali metals are responsible for providing a fixed
amount of charge and maintaining structural stability, while the cubic
framework formed by IIIA group elements and hydrogen is crucial for
high-temperature superconductivity. This work will inspire further experimental
exploration and take an important step in the exploration of low-pressure
stable high-temperature superconductors.
