Microwave nanoarchitectonics of black phosphorene for energy storage

Xenes are increasingly pivotal in various applications; particularly, black phosphorene (BP) has recently drawn profuse attention for its tremendous potential in electronics, spintronics, optoelectronics, and energy storage. However, its direct synthesis via bottom-up approaches remains elusive, largely burdened by cumbersome chemistry protocols. Herein, we report a novel large-scale, solution-phase synthesis approach of BP, in which concentrated orthophosphoric acid quickly turns to BP when exposed to microwave irradiation (∼800 W, cumulative ∼10 min consisting of 20 s pulses). While graphene/BP and MoS₂/BP heterolayers exhibit metallic and diodic behaviors, respectively, graphene/boron nitride/BP sandwich device displays excellent tunneling (∼20 mA). Interestingly, MoS₂-BP hybrid delivers a capacitance of 1,698.8 F g⁻¹, whereas graphene-BP exhibits a larger volumetric current density and a high capacitance of 2,863.5 F g⁻¹ with sustainable reversibility, high load, and high rate capability up to 50 mV s⁻¹. This synthesis provides a universal approach for large-scale production of 2D materials, thereby fueling future advancements in energy storage technologies.