Mn₃O₄–CeO₂ Hollow Nanospheres for Electrochemical Determination of Hydrogen Peroxide

Introducing hollow structure by self-assembly and hard-templating methods enables the increase of specific surface areas and reaction sites toward boosting the electrochemical sensing performance of the manganese oxide-based materials. In this work, a strategy of synthesizing Mn 3 O 4 –CeO 2 with nanosized hollow spheres was developed by employing cerium oxide as the support skeleton for a superior catalyzing effect toward hydrogen peroxide (H 2 O 2 ) electroreduction. Herein, the effect of molar ratios of Ce and Mn on the structure and electrocatalytic property of synthesized Mn 3 O 4 –CeO 2 hollow nanospheres was investigated. Profiting from abundant active sites, high porosity, large specific surface area, and the synergy of Mn 3 O 4 and CeO 2, the resulting Mn 3 O 4 –CeO 2 hollow nanospheres display a wide linear range response (0.005–17 mM) with high sensitivity (176.4 μA mM –1 cm –2 ) for H 2 O 2 determination. The developed sensor shows excellent stability, selectivity, and recovery for detecting H 2 O 2 in actual samples. This work finds an efficient way to construct hollow structure through self-assembly on a hard-templating surface, providing special insight into the electrochemical properties of transition-metal oxides.