Solution-Processed Organic–Inorganic Hybrid Anode Interface Layer for High-Performance Organic Photodiodes

The solution-processing technology of organic photodiodes (OPDs) stands as a core advantage distinguishing them from conventional silicon-based devices, offering several design opportunities for macroscopic structural innovations such as special-shaped, large-area, and flexible architectures. The anode interface layer (AIL), an indispensable component in OPD, is highly desired for processing techniques and physicochemical compatibility to meet the demands of high-performance devices. However, viable alternatives to the commercial material PEDOT:PSS remain scarce, with the narrow selection pool of solution-processed AIL materials. Here, a novel solution-processed organic–inorganic hybrid AIL (D149:Cu) is developed with tunable physicochemical properties, which combines the stability/high carrier mobility of inorganic components with the biocompatibility/flexibility of organic counterparts. The D149:Cu layer optimizes interfacial contact and energy level alignment, effectively enhancing photo-generated hole transport while suppressing dark-state electron injection from external circuit, thereby enabling OPDs with lower dark current (4.96 × 10 −9 vs 1.19 × 10 −7 A cm −2 ) and higher specific detectivity (9.09 × 10 12 vs 1.62 × 10 12 Jones) compared to PEDOT:PSS counterparts. Moreover, flexible D149:Cu-based OPD (≈51 µm-thick) is demonstrated, showing exceptional operational stability under mechanical flexing of 1500 bending cycles. This work alleviates the selection limitations of AILs in optoelectronic devices.