The pursuit of high-temperature quantum anomalous Hall (QAH) insulators faces fundamental challenges, including narrow topological gaps and low Curie temperatures ($T_{\text{C}}$) in existing materials. Here, we propose a transformative strategy using bilateral hydrogenation to engineer a robust QAH state in the topologically trivial ferromagnetic semiconductor ${\mathrm{Cr}}_{\text{2}}{\mathrm{Ge}}_{\text{2}}{\mathrm{Te}}_{\text{6}}$ via covalent orbital reconstruction. First-principles calculations reveal that by fundamentally rewiring the underlying orbital hybridization network, hydrogenation alters orbital occupations to shift preexisting Dirac points—originally embedded in the conduction bands—to the vicinity of the Fermi level in ${\mathrm{Cr}}_{\text{2}}{\mathrm{Ge}}_{\text{2}}{\mathrm{Te}}_{\text{6}}{\mathrm{H}}_{\text{6}}$. This electronic restructuring, coupled with spin-orbit coupling, opens a global topological gap of 118.1 meV, establishing a robust QAH state with Chern number $C=$ 3. Concurrently, this same orbital reconstruction effectively tunes the energy difference between the ligand $p$ and transition metal $d$ orbitals. This specific energy shift enhances ferromagnetic superexchange via the $d_{z^2}\text{−}{p}_z\text{−}{d}_{xz}$ channel, significantly strengthening the nearest-neighbor coupling $J_{\text{1}}$ by 3.06 times and switching $J_{\text{2}}$ from antiferromagnetic to ferromagnetic. Monte Carlo simulations based on the extracted exchange parameters indicate a pronounced enhancement of ferromagnetic stability compared with pristine ${\mathrm{Cr}}_{\text{2}}{\mathrm{Ge}}_{\text{2}}{\mathrm{Te}}_{\text{6}}$, and we stress that the absolute Curie temperature depends on the mapping to an effective spin model and thus should be interpreted primarily in terms of relative trends. The comparative enhancement of ferromagnetic stability after hydrogenation is a salient effect of this orbital tuning. This work establishes targeted orbital reconstruction driven by surface hydrogenation as a powerful route to simultaneously control topology and magnetism in 2D materials, providing a general route to engineer QAH phases with large gaps and high Chern numbers in van der Waals ferromagnetic semiconductors.

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• Magnetism
• Quantum anomalous Hall effect
• Topological phases of matter
• Ferromagnets
• Magnetic semiconductors
• Magnetic systems
• Topological materials
• van der Waals systems
• First-principles calculations