Complementary Passivation of Bidentate Aromatic Ligands Enables High‐Temperature Stable PbS Colloidal Quantum Dots Image Sensor

Abstract Achieving high‐temperature stability is critical for the commercialization of lead sulfide colloidal quantum dots (PbS CQDs) in short‐wave infrared imaging applications, particularly for automotive and consumer‐grade devices that require operation under elevated temperatures. This work addresses the challenges of high‐temperature stability of halide‐passivated PbS CQDs by introducing bidentate aromatic ligands as a complementary passivation in liquid‐phase ligand exchange. These ligands are shown to form robust bonds especially with CQDs {100} facets, effectively maintaining surface passivation and suppressing CQDs fusion at high temperatures. The CQDs films incorporating these ligands exhibit exceptional structural and chemical stability at 125 °C. Accelerated aging tests demonstrate that the CQDs photodiodes incorporating these ligands have long lifetimes of 168 h at 125 °C and 1500 h at 85 °C, which are over one‐order‐of‐magnitude longer than the control devices with halides alone. The CQDs image sensors, monolithically integrating by the optimal CQDs photodiodes and readout circuit, could capture high‐quality images until aging at 125 °C for 336 h. These findings support developing a scalable liquid‐phase ligand exchange method using bidentate aromatic ligands to prepare high‐temperature‐stable CQDs image sensors.