PVA:DNA Hybrid Dielectrics as Biocompatible Interfaces for High-Performance Organic Field-Effect Transistors

This study introduces a biologically inspired dielectric engineering strategy for organic field-effect transistors (OFETs) using deoxyribonucleic acid (DNA), poly(vinyl alcohol) (PVA), and their composite (PVA:DNA) as dielectric modification layers. The PVA:DNA hybrid uniquely merges the smooth surface morphology of PVA with DNA’s intrinsic polarity and nanostructured features, enhancing interfacial properties and device performance. Atomic force microscopy reveals PVA’s uniformity supports high-quality PTCDI-C13 semiconductor film growth, while DNA introduces nanoscale roughness from its phosphate-rich backbone. These composite yields balanced morphology and electrical properties, enabling stabilized polarization and efficient interfacial charge accumulation. Capacitance–voltage measurements confirm the PVA:DNA layer’s superior charge storage, attributed to interactions between PVA’s hydroxyl groups and DNA’s charged structure. OFETs with PVA:DNA dielectrics exhibit enhanced performance, including increased saturation current and high carrier mobility (2.63 cm2 V–1 s–1). Admittance spectroscopy shows reduced interface trap relaxation time, indicating faster trap dynamics and improved operational stability. Additionally, DNA’s UV sensitivity (Psensitivity ≈ 199.35) demonstrates potential for UV-responsive optoelectronics. This sustainable dielectric design supports high-performance, reduced charge trapping, and eco-friendly materials, aligning with the United Nations’ Sustainable Development Goals and offering a promising direction for next-generation organic electronics.