Borophene-Puckered Graphene Quantum Sheets-based Electronic Devices

The growing demand for self-powered wearable electronics and autonomous sensing systems has accelerated the development of high-performance triboelectric nanogenerators (TENGs) based on advanced two-dimensional materials. In this work, we report a scalable and environmentally benign sonochemical liquid-phase exfoliation strategy for the synthesis of few-layer borophene nanosheets using acetone as a low-boiling solvent. Controlled ultrasonication followed by centrifugation yields stable colloidal borophene dispersions with preserved B–B bonding and limited surface oxidation. Structural and chemical analyses using scanning electron microscopy (SEM) and energy-dispersive X-ray photoelectron spectroscopy (XPS) confirm the evolution of bonding from B–B in bulk boron to oxidized B–O species in borophene and the formation of interfacial B–C and B–O–Si linkages in the composite, indicating strong chemical integration and charge redistribution. Atomic force microscopy (AFM) reveals an increase in surface roughness from ∼4.97 nm (pristine PDMS) to ∼5.71 nm for the composite, facilitating enhanced charge generation. Optical characterization demonstrates semiconducting behavior with an optical bandgap of ∼3.67 eV and abundant surface-active sites favorable for interfacial charge trapping. To exploit these properties for energy harvesting, borophene was synergistically integrated with graphene into a flexible polydimethylsiloxane (PDMS) matrix to fabricate a contact–separation-mode TENG. Owing to enhanced surface roughness, improved dielectric polarization, and efficient interfacial charge transfer enabled by the hybrid two-dimensional fillers, the optimized borophene–graphene–PDMS TENG delivers an open-circuit voltage of ∼30 V, a current of ∼2.1 μA, and a surface charge of ∼15 nC, representing a 3-fold enhancement over pristine PDMS under practical operating conditions (20 N, 7 Hz). The device achieves an improved figure of merit, with energy conversion efficiency increasing from ∼1.1 (PDMS) to ∼3.3% for the composite, along with enhanced material and device Figure of Merit (FOM) values, confirming superior energy harvesting capability. The device exhibits excellent mechanical durability, stable long-term electrical output, rapid response, and effective energy storage capability, successfully charging capacitors and powering light-emitting diodes. Furthermore, reliable biomechanical energy harvesting and motion-sensing performance demonstrate strong potential for wearable and self-powered sensing applications. This study establishes a sustainable route for borophene synthesis and highlights its promise for next-generation flexible nanoenergy harvesting technologies.