ABSTRACT Additives and passivators are commonly used to regulate crystallization and suppress defects in halide perovskites. However, existing additives or passivation agents struggle to concurrently achieve effective defect passivation and efficient charge transport, and their passivation effects often fail to endure throughout device fabrication and operation. Here, we systematically screened a series of redox‐active, bifunctional passivation molecules with various functional motifs, namely si