Cotton-Like Three-Dimensional Sb₄O₅Cl₂ Structures: Synthesis and Ammonium Hydroxide Sensing

Nanostructured materials have emerged as valuable tools for the advancement of novel electrocatalysts. Among them, three-dimensional metal oxides have gained significant attention due to their excellent conductivity, cost-effectiveness, and unique design. This study focuses on the synthesis of cotton-like three-dimensional antimony oxychloride (Sb₄O₅Cl₂) structures through a straightforward precipitation method. The nanostructures exhibit immense potential for sensing applications. Electrochemical characterization reveals that the Sb₄O₅Cl₂ heterostructure demonstrates a remarkable double-layer capacitance of 662 F/cm², accompanied by excellent cyclic stability. The sensor's performance was tested for the detection of ammonium hydroxide (HA) in NaCl solution, yielding sensitivities ranging from 0.95 to 0.140 mA mM^-1 cm^-2 and a detection limit of 4.54 μM within a wide detection range of 0.3-250 mM. The sensor device possesses a distinctive cotton-like structure and is synthesized through a simple and cost-effective route.