Plasmonic perovskite photodetector with high photocurrent and low dark current mediated by Au NR/PEIE hybrid layer

Hybrid organic-inorganic perovskite photodetectors have gained significant attention due to their superior potential for optoelectronic applications, offering various advantages such as low-cost processing, high charge carrier mobility, and lightweight properties. However, these perovskite photodetectors exhibit relatively low absorption in the near-infrared (NIR) range, which limits their potential applications. Here, to address this challenge, the integration of gold nanorods (Au NRs) utilizing localized surface plasmon resonance (LSPR) effects in the NIR range has been developed, leading to enhanced light absorption in the active region and higher photocurrent generation. Additionally, ∼7.9 nm of thin polyethyleneimine ethoxylated (PEIE) interlayers were incorporated into the Au NR photodetectors, suppressing dark current by blocking charge injection. As a result, the synergistic effect of the Au NR/PEIE hybrid layer has led to a high-performance photodetector with a responsivity of 0.360 A/W and a detectivity of 1.81 × 10¹⁰ Jones, demonstrating a noticeable enhancement compared to the control device. Finite-difference time-domain (FDTD) simulations, morphological characterizations, and photoluminescence studies further support the mechanism for enhancing the performance of the device. We believe that our plasmon-enhanced protocol holds strong potential as a promising platform for perovskite optoelectronic devices.