One-Step Device Fabrication of Phosphorene and Graphene Interdigital Micro-Supercapacitors with High Energy Density

Rational engineering and simplified fabrication of high-energy micro-supercapacitors (MSCs) using graphene and other 2D nanosheets are of great value for flexible and integrated electronics. Here we develop one-step mask-assisted simplified fabrication of high-energy MSCs (PG-MSCs) based on the interdigital hybrid electrode (PG) patterns of stacking high-quality phosphorene nanosheets and electrochemically exfoliated graphene in ionic liquid electrolyte. The hybrid PG films with interdigital patterns were directly manufactured by layer-by-layer deposition of phosphorene and graphene nanosheets with the assistance of a customized interdigital mask, and directly transferred onto a flexible substrate. The resultant patterned PG films present outstanding uniformity, flexibility, conductivity (319 S cm^-1), and structural integration, which can directly serve as binder- and additive-free flexible electrodes for MSCs. Remarkably, PG-MSCs deliver remarkable energy density of 11.6 mWh cm^-3, outperforming most nanocarbon-based MSCs. Moreover, our PG-MSCs show outstanding flexibility and stable performance with slight capacitance fluctuation even under highly folded states. In addition, our simplified mask-assisted strategy for PG-MSCs is highly flexible for simplified production of parallelly and serially interconnected modular power sources, without need of conventional metal-based interconnects and contacts, for designable integrated circuits with high output current and voltage.