Orbital engineering of asymmetric Cu sites in MOFs for fenton reaction towards atomic surface manufacturing

Atomic surface manufacturing (ASM) of single-crystal 4H-silicon-carbide (4H-SiC) is fundamentally constrained by its extreme hardness and chemical inertness. Conventional Fenton-assisted ASM techniques require strongly acidic conditions, which fundamentally mismatches the optimal manufacturing environment for 4H-SiC and leads to low throughput and serious metal ion contamination. Here we report an orbital engineering strategy that creates asymmetric Nx-Cu-Oy sites in a metal-organic framework (Cu/ZIF-8) to enable efficient Fenton-like catalysis under neutral pH conditions. The asymmetric Nx-Cu-Oy sites significantly split copper d-orbitals, reconstruct the electronic structure, and reduce the ligand-to-metal charge transfer barriers, thereby accelerating the Cu(II)/Cu(I) redox kinetics for the Fenton reaction. Meanwhile, the vast specific surface area of metal-organic framework exposes a wealth of Nx-Cu-Oy sites without the need for ions to leach, which not only reduces wafer contamination risk but also meets the green manufacturing requirements. Consequently, Cu/ZIF-8 delivers an enhanced •OH generation under a neutral environment and achieves an improved ASM throughput for 4H-SiC, setting a benchmark in ASM of 4H-SiC. This study offers an intriguing bridge between molecular orbital design and manufacturing engineering and offer useful insights for future catalyst design and application. By engineering asymmetric copper sites in a metal-organic framework, researchers enable neutral-pH Fenton catalysis for atomic-scale polishing of silicon carbide, offering a sustainable alternative to traditional acidic processes.