Non-Equilibrium Pyrolysis Enables Nano-Confined Hetero-Interfaces in MOF-Derivatives for Advanced Dielectric Engineering

Interfacial polarization is a cornerstone of dielectric engineering, yet the thermal processing required for interface construction typically triggers grain coarsening, thereby undermining interfacial density and dielectric performance. Here, a microwave non-equilibrium pyrolysis strategy is developed to overcome this bottleneck. By preprogramming compositional heterogeneity in a Zn-Ni bimetallic MOF and introducing a carbon nanotube (CNT) scaffold with strong microwave coupling capability, rapid structural reconstruction is achieved on a second-level timescale. Microwave-induced plasma arc discharge and transient thermal shock facilitate the confined nucleation and nanoscale dispersion of ZnO/NiO within N-doped carbon, creating a dense multiphase heterogeneous interface. This non-equilibrium pathway effectively suppresses structural relaxation, significantly boosting interfacial polarization and localized electric-field perturbations. Consequently, the MOF-derivatives achieve potent electromagnetic wave attenuation reaching a minimum reflection loss of −55.16 dB at 1.85 mm. Furthermore, this second-level strategy enables the energy-efficient and high-throughput production of heterogeneous powders, which, when integrated into macro-periodic architectures, achieve an ultra-wide bandwidth of 11.98 GHz. This work establishes a non-equilibrium pyrolysis paradigm that enables next-generation electromagnetic wave absorbers with integrated ultra-wideband performance and a minimal energy footprint.