Advancements in Self‐Assembled Molecules to Hybrid Self‐Assembled Molecular Interlayers for Optimized Hole Transport Layer in Inverted Perovskite Solar Cells

Inverted (p-i-n) perovskite solar cells (PSC) have demonstrated significant promise compared to the conventional n-i-p architecture, owing to their improved operational stability, reduced hysteresis, and low-temperature fabrication process. These advantages make inverted devices particularly attractive for tandem and flexible applications. Self-assembled molecules (SAM) have been used lately in hole transport layer (HTL) of inverted PSC while the shortcomings like bad coverage and homogeneity, misalignment and weaker compactness with the substrate have appealed for its hybrid self-assembled molecular (HSAM) approaches. The compactness, coverage, and homogeneity of SAM can be further enhanced through HSAM, which leads to higher crystallinity, better band alignment, improved nucleation, and reduced non-radiative recombination losses in inverted PSC. Herein, the effect of HSAM is summarized at the HTL of inverted perovskite through their structural characteristics, interface passivation effects, crystallization modulation effect, dipole effect, redox behavior effects and the prevention of SAM aggregation in perovskite films for providing insights to broaden the impact of HSAM in inverted PSC for future research and development.