Dually anchoring dopants in boronate ester polymer films for boosting hole mobility and stability

Stabilizing radical cations derived from the oxidization of triphenylamine (TPA) moieties with bis(trifluoromethanesulfonyl)imide (TFSI−) has emerged as a general doping strategy for enhancing the hole transport of organic hole transport materials (OHTMs). However, the counter ions (such as Li+) of TFSI− seriously decrease the hole transport stability of OHTMs. Herein, we address this issue by dually anchoring LiTFSI in boronate ester polymers (BPs), in which boronate ester groups efficiently anchor Li+ ions, thus enhancing the stabilization effect of TFSI− anions to triplet diradicals generated by oxidizing TPA moieties. The LiTFSI-treated BP films exhibit hole mobilities (μp) up to 5.31 × 10−3 cm2 V−1 s−1, with conductivities (σ) up to 4.07 × 10−5 S cm−1, and good resistance to high temperatures, moisture, and solvents. Moreover, BP films can be programmably grown on substrates with various compositions and roughness. Our doping strategy would be a robust platform for developing new OHTMs and OHTM-enabled device interfaces. [Display omitted] •Programmable growth of boronate ester polymer (BP) films on various substrates•A simple doping strategy enhances the hole mobility of BP films•Doped BP films exhibits good resistance to high temperatures, moisture, and solvents He et al. present a nondestructive doping system to realize high-efficiency hole transport based on dually anchoring LiTFSI in boronate ester polymers. This approach exhibits high substrate adaptability and environmental stability, providing a robust platform to address interface issues in electronic and optoelectronic devices.