Design of Ni(OH)2 nanocages@MnO2 nanosheets core-shell architecture to jointly facilitate electrocatalytic dynamic for highly sensitive detection of dopamine.

In this work, Ni(OH)2 nanocages@MnO2 nanosheets core-shell architecture (Ni(OH)2 NCs@MnO2 NSs CSA) was successfully prepared through coordinated etching and precipitation (CEP) route followed by hydrothermal reaction, and then tested as sensitive electrode material for detection of dopamine (DA). The three dimensional (3D) hollow Ni(OH)2 core effectively prevented the aggregation of MnO2 NSs, leading to high utilization rate of MnO2 NSs. Meanwhile, the two dimensional (2D) MnO2 shell endowed Ni(OH)2 NCs with larger specific area and abundant diffusion channels, facilitating mass transport. Ni(OH)2 NCs@MnO2 NSs CSA modified glassy carbon electrode (GCE) exhibited two satisfying sensitivities of 467.1 and 1249.9 μA mM-1 cm-2 within the two linear ranges of 0.02-16.30 μM and 18.30-118.58 μM, respectively. Furthermore, Ni(OH)2 NCs@MnO2 NSs CSA/GCE presented low detection limit of 1.75 nM and short response time of 1.14 s. Overall, Ni(OH)2 NCs@MnO2 NSs/GCE looks promising for analytical sensing of DA thanks to its prominent electrocatalytic dynamic issued from the 3D hollow structure@2D nanosheets core-shell architecture.