Efficient perovskite solar cells based on self-assembled monolayers as hole transport layer

Metal halide perovskite solar cells have achieved impressive development in power conversion efficiencies (PCEs) in both single-junction and tandem devices, with efficiency up to 26.14% and 33.9%, respectively. However, the unsatisfied long-term stability of functional layers, the self-degradation process and ion migration become challenges to realized practical applications. Thus, the practical and effective strategy that simultaneously improves the efficiency and stability of perovskite solar cells are highly desired. The outstanding perovskite solar cells with PCEs beyond 25% are mostly fabricated with Spiro-Ome TAD. Comparatively, the new star hole transport layers (HTL) of self-assembled monolayers (SAMs) attract much attention due to their distinct benefits in transparency, diversity, stability, sensitivity, selectivity, and surface passivation ability. However, the carrier dynamics and mechanisms of perovskite solar cells based on SAMs are still obscure and confusing. Herein, we proposed to prepare perovskite solar cells with MEO-4PACz SAMs as hole transport layers, and studied its carrier dynamics and effects on devices performance. Moreover, the joint synergistic effects of SAMs and PEDOT:PSS will be conducted systematically in this work.