Preparation of flake hexagonal BN and its application in electrochemical detection of ascorbic acid, dopamine and uric acid

•Flake BN was synthesized by LCS and carbothermal reduction and nitridation method.•The flake BN possesses high surface area (936 m2/g) and large void volume (0.705 cm3/g).•The sensor with high selectivity is fabricated for the first time to detect AA, DA and UA.•The sensor exhibits lower determination limits and wider linear ranges with good anti-interference ability. Flake hexagonal boron nitride (h-BN) was synthesized combining low temperature combustion synthesis (LCS) and carbothermal reduction and nitridation methods. The obtained h-BN is characterized as amorphous and layered structure with high density defects and active surface groups. The electrochemical properties of the flake BN modified glassy carbon electrode were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These results demonstrate this kind of novel electrodes exhibit excellent electrocatalytic activity and high selectivity for electrochemical detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The liner relationships between current intensities and concentrations are found to be 30–1000, 0.5–150 and 1–300 μM, with detection limits of 3.77, 0.02 and 0.15 μM for AA, DA and UA, respectively. The sensor also exhibits good anti-interference ability, high stability and reproducibility.