Magnetically Aligned Graphite Flakes Electrodes for Excellent Sensitive Detection of Hydroquinone and Catechol

Natural graphite has a large electrical conductivity in plane direction, hundreds times of that in vertical direction. Regulating graphite flakes perpendicular to the plane will improve the performance of the sensor. As a non-connected method, magnetic field-assisted orientation can be no-additives. However, some studies believe that diamagnetic materials are non-magnetic, and must be doped by ferromagnetic materials before oriented by a magnetic field. Here, original graphite flakes were vertically oriented by a low magnetic field during the electrode preparation to increase effective surface area. The performance of electrode was enhanced in both potassium ferricyanide/potassium ferrocyanide probe system and detection of hydroquinone (HQ) and catechol (CC). For HQ and CC detection, the sensitivities of vertically oriented graphite flakes electrode are 5.05 times and 6.35 times higher than that of graphite flakes without magnetic field, respectively. This magnetic alignment technology could construct other electrode materials for electrochemical sensors.