CoWO₄-Delaminated Co Layered Double Hydroxide Nanosheets for Enhanced Electrocatalytic Oxidation of Hydrazine in Real Samples

The development of layered double hydroxides (LDHs) with tailored architectures and investigation of their electrochemical properties for hydrazine (HZ) detection presents both significant challenges and promising opportunities across various applications. In this work, CoWO₄-delaminated Co LDH nanosheets (NSs) were successfully synthesized and demonstrated their effectiveness as an electrochemical sensing platform for HZ oxidation. The synthesized Co LDHNS@CoWO₄ exhibits a hierarchical structure with expanded interlayer spacing, which enhances the availability active sites and facilitates charge transfer. The amorphous CoWO₄ introduces structural defects and unsaturated sites, thereby promoting ion transport, accelerating surface reactions, and improving overall catalytic performance. This engineered heterostructure creates synergistic effects that dramatically enhance electrochemical performance. The developed sensor displayed high sensitivity in detecting HZ, achieving a low detection limit of 0.1 nM and a broad linear response spanning from 0.001 μM to 4000 μM. The practical performance of Co LDHNS@CoWO₄ was successfully demonstrated through HZ detection in real water samples.