Single microparticle applied in magnetic-switchable electrochemistry

In this work we demonstrated the micromanipulation of a single magnetic microparticle (Fe3O4) modified with Prussian blue (PB) for use in magnetic-switchable electrochemistry. A single Fe3O4-PB microparticle with 120 μm was isolated in an electrochemical microcell (20 μL), in which a fine control of PB electrochemical process on carbon electrode (Ø = 4.0 mm) was obtained. For cyclic voltammetry, redox processes attributed to PB/PW (Prussian blue/Prussian white) one electron redox couple were observed, however the capacitive currents were very high. On the other hand, by using differential pulse voltammetry, a maximum faradaic current for anodic peak of 200 nA cm− 2 at 0.06 V was observed. Several and high stable chronoamperograms were obtained by “switch on” and “switch off” magnetic commutative states for a single microparticle, showing that the system developed here can be very promising for application in electrochemistry.

► We demonstrated the micromanipulation of a single Fe3O4-PB microparticle (120 μm).
► The single microparticle was isolated in an electrochemical microcell of 20 μL.
► The process redox of PB was controlled by magnetic-switchable electrochemistry.
► A fine control of PB electrochemical process on carbon electrode was obtained.
► The system developed here showed to be promising for application in electrochemistry.