Preparation of Ni/Co layered double hydroxide hollow cakes as an electrochemical sensing platform for monitoring the production of hydrogen peroxide in formulated beverages

Beverages containing redox-active compounds may produce hydrogen peroxide (H2O2) during shelf storage. Hydrogen peroxide (H2O2), a reactive oxygen species (ROS), plays a crucial role in biological systems. Anomaly concentration of H2O2 may cause irreversible tissue damage. Therefore, it is challenging work to design nanomaterials with unique structures and explore their electrochemical activity for accurately and highly sensitively detecting H2O2 in beverages. In this study, the Ni/Co layered double hydroxide hollow cake (NiCo-LDH HC) was constructed using the Co-zeolitic imidazolate framework (Co-ZIF) as precursors by simple ion etching. The nanosheets LDH were self-assembled into nano-hydrangea shapes, which furtherly covered the HC structures, resulting in more effective active sites, more electrochemical catalytic sites exposure, and accelerated ion mass transfer. The prepared NiCo-LDH HC was used as a working electrode for H2O2 electrochemical sensing. The results show that a sensitivity of 7050 μA mM−1 cm−2 and a limit of detection (LOD) of 0.22 μM (S/N = 3) were obtained with good electrocatalytic activity. Finally, the concentrations of H2O2 in functional beverages and non-functional beverages were measured under ambient and 'potentiated' conditions (adding a reducing agent ascorbic acid (AA)). The results show that the presence of AA can significantly increase the levels of H2O2 due to the reaction between anti-oxidant mixtures and dissolved oxygen in beverages.