High-performance black phosphorus (BP)-based micro-supercapacitors (MSCs) hold immense promise for wearable electronics but remain hampered by the material’s intrinsic instability and sluggish electron kinetics. Herein, a two-dimensional phosphorene and bismuthene (2D BP/Bi) heterojunction via liquid nitrogen-assisted exfoliation and mask-assisted filtration was developed as a robust bifunctional electrode for integrated flexible energy-sensing systems. The heterostructure effectively suppresses nanosheet restacking and enhances interfacial stability through strong P–O–Bi covalent bonding and interfacial synergy. Simultaneously, the incorporation of bismuthene constructs high-speed electron transport channels, significantly facilitating ion diffusion and charge transfer. Consequently, the optimized electrode achieved a high areal capacitance of 7.6 mF·cm⁻² (1.6-fold enhancement over pure BP) and an ultra-long lifespan with 92.1% retention after 30,000 cycles. Notably, by tailoring the gel electrolyte with DMSO, the device exhibited remarkable freeze-tolerance, maintaining 70% capacitance at −35 °C. Furthermore, an all-flexible integrated system combining the MSC with a pressure sensor was constructed using graphene current collectors, enabling continuous, self-sustained physiological monitoring. This work offers critical insights into interface engineering for designing high-performance BP-based MSCs and paves the way for extreme-environment wearable applications.

Simplifying the technology for regulating dielectric properties and enriching electromagnetic loss mechanisms of layered electromagnetic wave (EMW) absorption materials still faces challenges. Herein, we propose a simple and eco-friendly sieving strategy to control the lateral size (3–50 μm) of multilayered SiP₂ flakes for regulating dielectric constants. Moreover, hierarchical-structured 2D SiP₂@0D Ni nanoparticles/1D Ni chains low-dimensional aggregates are in-situ constructed on SiP₂ flakes via a two-step hydrothermal method to enhance interfacial polarization and electromagnetic synergistic effects. When the lateral size was controlled at 11 μm (SiP₂-300), the intrinsic SiP₂ exhibits strong reflection loss (RL) value of −38.9 dB at 1.7 mm. Notably, the construction of 2D/0D/1D SiP₂@Ni not only maintains a strong RL of −40.1 dB, but also shifts the corresponding absorption frequency from original Ku-band (11.8 GHz) to C-band (7.2 GHz). More importantly, the effective absorption bandwidth is broadened from 2.9 GHz to 4.1 GHz benefiting from the construction of electromagnetic synergy networks. Additionally, the radar cross section (RCS) value (29.14 dB⸱m²) evaluated by the computer simulation technology (CST) results for SiP₂@Ni–S2 confirm the excellent dissipation ability. This study provides a new strategy for the application of layered absorbers with low-frequency, broadband and adjustable EMW properties.