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 −1 Pb n Br 3 n +1, n = 4) absorber layer using Ti 3 C 2 T x 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 × 10 12 Hz 1/2 /W) at 2.0 V bias under laser illumination (λ ex ∼ 405 nm, P in ∼ 0.62 mW/cm 2 ), 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.