Multi‐Bridged Lewis‐Functionalized Self‐Assembled Monolayers for Enhanced Interfacial Affinity in Perovskite Photoelectric Sensors

This study introduces an asymmetric self-assembled monolayers (SAMs) architecture, ((5H-Diindolo[3,2-a:3',2'-c]carbazole-5,10,15-triyl)tris(propane-3,1-diyl))triphosphonic acid (3PATAT-C3), designed to advance interfacial engineering in perovskite photoelectric devices. The molecular design integrates three phosphonic acid anchoring groups, enabling robust bonding with the substrate to enhance sustainability. Strategically positioned Lewis basic oxygen and sulfur heteroatoms drive synergistic interactions, addressing the limitations of conventional SAMs by optimizing interfacial contact and surface coverage. The face-on orientation of the molecules promotes energy alignment (work function: 5.18 eV) and superior crystallization (grain size: 0.784±0.315 μm). These features collectively improve moisture resistance and charge transport efficiency. Performance metrics demonstrate significant enhancements, including a power conversion efficiency of 21.74 %, a reduction in dark current density (8.93×10^-9 A/cm²), and a shot noise-limited detectivity of 1.01×10¹³ Jones. By applying multi-bridging strategies and sustainable chemistry principles, this work offers a paradigm shift for designing high-performance optoelectronic devices.