Additive Engineering of Ruddlesden–Popper Perovskites with MXene Nanoflakes: Toward Enhanced Photoresponsivity, Detectivity, and Stability

Ruddlesden–Popper perovskites (RPPs) have drawn a lot of attention due to their structural stability under ambient atmosphere compared to bulk counterparts. However, their relatively low photoresponsivity, due to quantum and dielectric confinement effects, is still a key challenge in the development of efficient photodetectors. Present work reports one-step additive engineering of the RPP ((CH)2(MA)n−1PbnBr3n+1, n = 4) absorber layer using Ti3C2Tx MXene nanoflakes, which formed a robust heterointerface. Surface functional groups of MXene retard the crystallization rate of RPP thin films, thereby spurring the enhancement of the optical, structural, and morphological properties of RPP-MXene hybrids. Unencapsulated hybrid (n = 4 + 1.5 mM) photodetectors have shown improved responsivity (∼151 A/W) and detectivity (∼14.21 × 1012 Hz1/2/W) at 2.0 V bias under laser illumination (λex ∼ 405 nm, Pin ∼ 0.62 mW/cm2), outperforming pristine devices significantly. Over 50 cycles, hybrid devices maintained stable peak photocurrent, while photocurrent of pristine devices degraded by ∼35%, indicating a unique platform to explore a wide range of MXenes to overcome the stability issues associated with perovskites.