Perovskite–Polymer Heterojunction Photodetectors with >90% NIR EQE Enabled by Oxygen-Directed 2D Side-Chain Design in n-Type Acceptors
발표자
박지원 (울산과학기술원)
연구책임자
양창덕 (울산과학기술원)
공동저자
박지원 (울산과학기술원), 양창덕 (울산과학기술원)
초록
내용
Side-chain engineering is powerful for tuning molecular properties, yet it has been scarcely applied to n-type semiconductors in perovskite–organic heterojunction photodetectors (POH-PDs). Here we design two n-type nonfullerene acceptors (Y1PhO, Y2PhO) with oxygen-position-tuned 2D-conjugated outer side chains, enabling control of bulk photophysics and buried-interface energetics. Compared with Y6, both show larger dipole moments, higher dielectric constants, and up-shifted frontier-orbital energies, while reduced backbone planarity suppresses over-aggregation to yield smoother PM6:acceptor films and improved coupling to CsFA perovskite. The PM6:Y2PhO device delivers >90% NIR EQE, R = 0.623 A W-1, D* = 7.05×1012 Jones at 830 nm, and LDR = 109.1 dB, outperforming Y6. Oxygen-position side-chain engineering thus offers a compelling route to ultrahigh-sensitivity broadband PDs.