Passivation of black phosphorus as organic-phase enzyme platform for bisphenol A determination

Black phosphorus (BP) has a high charge-carrier mobility (∼1000 cm² V^-1 s^-1), but the bare BP degrades rapidly in the presence of oxygen and water which limits the application of the BP. In this study, a simple, non-covalent passivation strategy is developed by modifying of the BP with hexamethylendiamine (HA). The functionalized BP exhibits good stability over 4 weeks. The organic phase interdigital electrode which is constructed by stable HA/BP and tyrosinase displays lowest noise signal (0.025 nA) and relatively low detection limit (10 nmol L^-1) for bisphenol A. This work provides a new strategy for construction of novel biofuel cell, bioelectronics and biosensors.