  The pursuit of room-temperature superconductors has recently advanced with
the discovery of high-temperature superconductivity in compressed hydrides,
although sustaining the superconductivity of hydrides at ambient pressure
remains challenging. In parallel, $sp^3$-bonded frameworks comprising
lightweight elements (\textit{e.g.}, boron and carbon) have emerged as another
avenue for developing ambient-pressure superconductors. However, despite their
stability at low pressures, the critical temperature ($T_\text{c}$) values
observed in these materials have not yet reached the impressive benchmarks set
by hydride-based superconductors. Here we propose a novel design strategy for
achieving high-temperature superconductivity at ambient pressure by integrating
hydride units into B-C clathrate structures. This approach exploits the
beneficial properties of hydrogen, the lightest element, to enhance the
superconductivity beyond that of the parent compounds. For instance, our
computational predictions indicate that doping SrB$_3$C$_3$ with ammonium
(NH$_4$) yields a SrNH$_4$B$_6$C$_6$ compound with an estimated $T_\text{c}$ of
85 K at ambient pressure -- more than double that of its precursor (31 K).
Extensive substitution across the periodic table results in a family of
MNHNH$_4$B$_6$C$_6$ superconductors that are predicted to be superconducting at
ambient pressure. These compounds can potentially be synthesized using
high-pressure techniques and then quenched to ambient conditions, with the
highest predicted ambient-pressure $T_\text{c}$ of 115 K in PbNH$_4$B$_6$C$_6$.
Our findings present a promising strategy for discovering high-$T_\text{c}$
superconductors at ambient pressure, potentially revolutionizing technologies
reliant on superconducting materials.
