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Abstract 2D materials with long‐range ferromagnetic order hold promises for the development of compact spintronic devices with unprecedented multifunctionality and tunability. Among various 2D magnets, self‐intercalated transition metal chalcogenides Cr1+δTe2 exhibit unique features, especially excellent ambient stability and intrinsic ferromagnetic ordering above room temperature, which are critical requirements for real‐life device applications. Despite the many investigations of the magnetic properties of the Cr1+δTe2 family on the averaging macroscopic level, the domain evolution on the microscale, which is vital to nanoscale spintronics, is yet to be fully understood. Here, the evolution of magnetic behaviors of Cr0.92Te crystals is presented on both macro‐ and micro‐scales under magnetic field and thermal excitation. The crystal exhibits a high Curie temperature (Tc ≈ 343 K) among the Cr1+δTe2 family with weak magnetic anisotropy and in‐plane magnetic easy axis. Utilizing magnetic force microscopy, a pristine multidomain state and typical domain‐switching behavior are observed. Moreover, the evolution of domain texture under thermal excitation shows statistical power‐law scaling as approaching Tc. The results provide microscopic insight into the ferromagnetic behavior of a room‐temperature quasi‐2D crystal, which can be useful for further engineering of domain texture in low‐dimensional magnetic materials.

Abstract The active and stable palladium (Pd) based catalysts for CH4 conversion are of great environmental and industrial significance. Herein, we employed N2 as an optimal activation agent to develop a Pd nanocluster exsolved Ce‐incorporated perovskite ferrite catalyst toward lean methane oxidation. Replacing the traditional initiator of H2, the N2 was found as an effective driving force to selectively touch off the surface exsolution of Pd nanocluster from perovskite framework without deteriorating the overall material robustness. The catalyst showed an outstanding T50 (temperature of 50% conversion) plummeting down to 350°C, outperforming the pristine and H2‐activated counterparts. Further, the combined theoretical and experimental results also deciphered the crucial role that the atomically dispersed Ce ions played in both construction of active sites and CH4 conversion. The isolated Ce located at the A‐site of perovskite framework facilitated the thermodynamic and kinetics of the Pd exsolution process, lowering its formation temperature and promoting its quantity. Moreover, the incorporation of Ce lowered the energy barrier for cleavage of C─H bond, and was dedicated to the preservation of highly reactive PdOx moieties during stability measurement. This work successfully ventures uncharted territory of in situ exsolution to provide a new design thinking for a highly performed catalytic interface.