Double-Layered Strategy for Broadband Photomultiplication-Type Organic Photodetectors and Achieving Narrowband Response in Violet, Red, and Near-Infrared Light

Abstract

Broadband photomultiplication-type organic photodetectors (PM-OPDs) were prepared with PMBBDT:PY3Se-2V (1:1, wt/wt) as the absorbing layer (AL) and PC 71 BM:P3HT (100:5, wt/wt) as the photomultiplication layer (PML) on the basis of the sandwich structure. The incident photons from ultraviolet light to the near-infrared region can be harvested by AL. The rather less P3HT in PML can produce plenty of isolated hole traps with P3HT surrounded by PC 71 BM; the electron tunneling injection induced by trapped holes near the Ag electrode can lead to the photomultiplication (PM) phenomenon. The performance of PM-OPDs can be effectively improved by optimizing the AL thickness. The optimal PM-OPDs exhibit a broad spectral response from 300 to 1050 nm as well as an external quantum efficiency (EQE) of 5800% at 340 nm at 10 V bias, along with a specific detectivity (D*) of 3.78 × 10 13 Jones. The spectral response of PM-OPDs is controlled by the trapped-hole distribution near the Ag electrode, primarily originating from the photogenerated holes in AL. To further optimize the spectral response of PM-OPDs, the optical filter layer (OFL) was used to manipulate light field distribution in AL. The violet, red, and near-infraredlight PM-OPDs were developed by employing different OFLs.

CuBi2O4nanocrystals integrated with polyaniline nanobelt arrays for weak light photomultiplication type photodetector

“…These adaptable devices can be used in study areas where lower irradiance detection is necessary since the greater EQE enables us to detect low-intensity photons. 64,[71][72][73] Similar to the responsivity of the photodetector device, EQE also decreases on increasing the illumination intensity as depicted in the graph in Fig. 7d.…”

“…These adaptable devices can be used in study areas where lower irradiance detection is necessary since the greater EQE enables us to detect low-intensity photons. 64,71–73…”

Recent Progress on OrganicNear‐InfraredPhotodetectors: Mechanism, Devices, and Applications†

“…[ 130 ] In recent years, scientists have been enthusiastic about fabricating narrowband NIR organic photodetectors. [ 115,132‐153 ] Unlike inorganic narrowband NIR photodetectors, a dichroic prism or set of optical filters is typically required in front of the PDs, [ 154 ] which is unfavorable for the miniaturization and integration of devices. [ 155‐159 ] There are several ways to fabricate narrowband NIR organic photodetectors, such as using the method of charge collection narrowing, [ 135 ] using the method of exciton dissociation narrowing, [ 132 ] charge injection narrowing strategy, [ 81,160‐161 ] using optical microcavity structure in the device, [ 133‐134,136,162 ] , and fabricating appropriate narrowband materials.…”

High Responsivity of Narrowband Photomultiplication Organic Photodetector via Interfacial Modification

“…[15][16][17] Besides those approaches, the recently developed charge narrowing strategy that employs a thick active layer can also yield narrowband photodetection without increasing the system complexity. [3,5,13,18,19] For instance, the filterless narrowband OPDs based on charge collection narrowing utilizing a bulkheterojunction device structure, and exciton dissociation narrowing, and planar heterojunction device structure have been reported. [20][21][22][23] For photomultiplication-type OPDs (PM-OPDs) with external quantum efficiency (EQE) far exceeding 100%, based on the trap-assisted charge injection principle, [24] a so-called charge injection narrowing (CIN) strategy has been also demonstrated for narrowing its response spectral band.…”