Black phosphorus (BP) is one of the most attractive graphene analogues, and its properties make it a promising nanomaterial for chemical sensing. However, mono- and few-layer BP flakes are reported to chemically degrade rapidly upon exposure to ambient conditions. Therefore, little is known about the performance and sensing mechanism of intrinsic BP, and chemical sensing of intrinsic BP with acceptable air stability remains only theoretically explored. Here, we experimentally demonstrated the first air-stable high-performance BP sensor using ionophore coating. Ionophore-encapsulated BP demonstrated significantly improved air stability. Its performance and sensing mechanism for trace ion detection were systematically investigated. The BP sensors were able to realize multiplex ion detection with superb selectivity, and sensitive to Pb(2+) down to 1 ppb. Additionally, the time constant for ion adsorption extracted was only 5 s. The detection limit and response rate of BP were both superior to those of graphene based sensors. Moreover, heavy metal ions can be effectively detected over a wide range of concentration with BP conductance change following the Langmuir isotherm for molecules adsorption on surface. The simplicity of this ionophore-encapsulate approach provides a route for achieving air-stable intrinsic black phosphorus sensors that may stimulate further fundamental research and potential applications.

High-performance dielectric materials continue to arouse considerable interest due to their application in the field of solid state capacitors.

Lateral heterostructures fabricated by two-dimensional building blocks have opened up exciting realms in material science and device physics. Identifying suitable materials for creating such heterostructures is urgently needed for the next-generation devices. Here, we demonstrate a novel type of seamless lateral heterostructures with excellent stabilities formed within pristine arsenene and antimonene. We find that these heterostructures could possess direct and reduced energy gaps without any modulations. Moreover, the highly coveted type-II alignment and the high carrier mobility are also identified, marking the enhanced quantum efficiency. The tensile strain can result in efficient bandgap engineering. Besides, the proposed critical condition for favored direct energy gaps would have a guiding significance on the subsequent works. Generally, our predictions not only introduce new vitality into lateral heterostructures, enriching available candidate materials in this field, but also highlight the potential of these lateral heterostructures as appealing materials for future devices.

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