Mesoporous MnFe2O4 nanocrystal clusters for electrochemistry detection of lead by stripping voltammetry

• Mesoporous MnFe2O4 nanocrystal clusters were modified on GCE.
• Favorable sensitivity (19.9 μA μM− 1) and LOD (0.054 μM) for Pb2 + were achieved.
• The modified GCE exhibits high selectivity and good anti-interference.
• It offered excellent stability and practical applicability for detection of Pb2 +.

High-adsorption MnFe2O4 nanocrystal clusters (MnFe2O4 NC) with mesoporous structure were used for selective analysis of Pb2 + by square wave anodic stripping voltammetry (SWASV) in this work. The as-prepared MnFe2O4 NCs with diameter of 200–400 nm and mesoporous structure composed of nanocrystals with a size of about 8–12 nm were characterized using SEM, HRTEM and XRD. Electrochemical properties were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The chemical and electrochemical parameters influencing on deposition and stripping of metal ions, such as supporting electrolytes, pH value, deposition potential, and deposition time, were also studied. The MnFe2O4 NC modified GCE has a high selectivity toward Pb2 + with a favorable sensitivity (19.9 μA μM− 1) and LOD (0.054 μM) for Pb2 + under the optimized conditions while the response to Cd2 +, Hg2 +, Cu2 + and Zn2 + is poor. No interference from Cd2 +, Zn2 + and Hg2 +, favorable stability and potential practical applicability were recognized in the electrochemical determination of Pb2 +. The above results provided a potential material for the design of new sensing materials in the application field of electrochemical detection toward toxic metal ions.