Vol.:(0123456789) 1 3 Chemical Papers https://doi.org/10.1007/s11696-022-02248-3 ORIGINAL PAPER Magnetically aligned graphite fakes electrodes for excellent sensitive detection of hydroquinone and catechol Yan Li 1  · Tingxia Wu 1  · Lingyu Song 1  · Yongbao Zhu 1  · Yizhe Chen 2  · Yufu Huang 2  · Junping Tang 2  · Kai Cheng 3  · Donghai Lin 2  · Guosong Chen 1 Received: 19 December 2021 / Accepted: 19 April 2022 © Institute of Chemistry, Slovak Academy of Sciences 2022 Abstract Natural graphite has a large electrical conductivity in plane direction, hundreds times of that in vertical direction. Regulating graphite fakes perpendicular to the plane will improve the performance of the sensor. As a non-connected method, magnetic feld-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 feld. Here, original graphite fakes were verti- cally oriented by a low magnetic feld during the electrode preparation to increase efective surface area. The performance of electrode was enhanced in both potassium ferricyanide/potassium ferrocyanide probe system and detection of hydroqui- none (HQ) and catechol (CC). For HQ and CC detection, the sensitivities of vertically oriented graphite fakes electrode are 5.05 times and 6.35 times higher than that of graphite fakes without magnetic feld, respectively. This magnetic alignment technology could construct other electrode materials for electrochemical sensors. Keywords Graphite · Magnetically orientation · Electrochemical detection · Sensor · Hydroquinone · Catechol Introduction Under an external magnetic feld, some micro/nano-material arrays with orderly arrangement can be obtained (Rikken et al. 2014; Gong and Zhang, 2019). These arrangements have diferent properties from randomly arranged mate- rials in terms of electrical, (Wang et al. 2019b; Yu et al. 2019) mechanics, (Erb et al. 2012) permeability, (Chen et al. 2018) magnetic, (Fonseca et al. 2020) catalysis, (Wang et al. 2019a) optics, (Dan et al. 2012) etc. Most of these materials are paramagnetic or ferromagnetic or composite materials containing ferromagnetic materials such as magnetite. In contrast, it is far more difcult to orient diamagnetic mate- rials. For example, a strong magnetic feld of up to 10 T must be used to orient the unmodifed diamagnetic carbon nano- tubes. (Walters et al. 2001; Zaric et al. 2004) The exceptions were successfully oriented the diamagnetic anisotropic gra- phene using a magnetic feld of only 0.1 T (Lin et al. 2017; Li et al. 2020; Lu et al. 2020). Graphite is much cheaper than graphene. Graphite, as a kind of material with low resistance, easy to process, electro- chemically inert, it has been widely used to manufacture fat electrodes. Graphite has a naturally faky structure. (Renedo et al. 2007; Mohamed, 2016; Silva et al. 2019) According to the measurements of single crystals of graphite by Krishnan, (Krishnan and Ganguli, 1939) Dutta (Dutta, 1953) and Pri- mak, (Primak and Fuchs, 1954) the electrical conductivity in the planar direction of the graphite fakes is approximately several hundred to ten thousand times than that of in the normal direction. The electrical conductivity of graphite in the vertical direction is 2 × 10 4 –3 × 10 4  (ohm cm) −1 , but in the horizontal direction is 150–230 (ohm cm) −1 . This dif- ference is due to the huge layered bonds in graphite crystal. * Donghai Lin dhlin@sspu.edu.cn * Guosong Chen gschen@njtech.edu.cn 1 College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 210009, China 2 Shanghai Key Laboratory of Engineering Materials Application and Evaluation, Shanghai Engineering Research Center of Advanced Thermal Functional Materials, School of Energy and Materials, Shanghai Polytechnic University, Shanghai 201209, China 3 Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China