Transparent Organic Field-Effect Transistors Based on Patterned Carbon Electrodes and Vinylene-Bridged Diketopyrrolopyrrole Polymers

The advancement of organic electronics has intensified the demand for high-performance transparent organic field-effect transistors (OFETs), yet achieving simultaneous optical transparency and electrical efficiency in both electrodes and semiconductors remains a critical challenge. Here, we present a sustainable strategy utilizing recycled acrylonitrile butadiene styrene (ABS) resin as a carbon precursor to fabricate patterned amorphous carbon electrodes via chemical vapor deposition (CVD). These electrodes demonstrate exceptional conductivity (1140 S/m) and transparency (97% at 9 nm thickness), offering an eco-friendly pathway for repurposing plastic waste. Coupled with vinylene-bridged diketopyrrolopyrrole (DPP)-based conjugated polymers DPPVTV and DPPTVT─engineered to minimize absorption in the visible range─the resulting OFETs achieved remarkable performance. Devices based on these two conjugated polymers exhibited hole mobilities of 0.113 and 0.124 cm²/V s, respectively, alongside average visible-light transmittances exceeding 90%. The synergy of high conductivity, optical clarity, and compatibility with diverse semiconductors underscores the versatility of CVD-grown carbon electrodes. This work not only addresses material sustainability but also advances the development of next-generation transparent and wearable electronics, bridging ecological innovation with cutting-edge device performance.