Polarimetric Image Sensor and Fermi Level Shifting Induced Multichannel Transition Based on 2D PdPS

Abstract

2D materials have been attracting high interest in recent years due to their low structural symmetry, excellent photoresponse, and high air stability. However, most 2D materials can only respond to specific light, which limits the development of wide‐spectrum photodetectors. Proper bandgap and the regulation of Fermi level are the foundations for realizing electronic multichannel transition, which is an effective method to achieve a wide spectral response. Herein, a noble 2D material, palladium phosphide sulfide (PdPS), is designed and synthesized. The bandgap of PdPS is around 2.1 eV and the formation of S vacancies, interstitial Pd and P atoms promote the Fermi level very close to the conduction band. Therefore, the PdPS‐based photodetector shows impressive wide spectral response from solar‐blind ultraviolet to near‐infrared based on the multichannel transition. It also exhibits superior optoelectrical properties with photoresponsivity (R) of 1 × 103 A W−1 and detectivity (D*) of 4 × 1011 Jones at 532 nm. Moreover, PdPS exhibits good performance of polarization detection with dichroic ratio of ≈3.7 at 808 nm. Significantly, it achieves polarimetric imaging and hidden‐target detection in complex environments through active detection.

Self‐Trapped Excitons in 2D SnP2S6 Crystal with Intrinsic Structural Distortion

“…[47] This issue can be solved by means of transferring electrode and optimizing device structure, [48,49] which will not be studied in this work. The responsivity (R) was calculated to evaluate the photodetection performance at different wavelengths according to the following equation [50] :…”

“…[23] At a low power density of 0.16 mW cm -2 , a high responsivity of ≈8.5 A W -1 was obtained (Figure 4f). Furthermore, the detectivity (D*) was calculated by combing the R and dark current (I dark ) through the following equation: [50] /2 dark D R A eI = *…”

Near-Infrared Polarimetric Image Sensors Based on Ordered Sulfur-Passivation GaSb Nanowire Arrays

“…With innovations in detection and sensing science, multidimensional optical detection technology has come into being. The polarimetric imaging sensor can extend the detection of photoelectric signal from light wavelength and intensity to a light polarization vector, which exhibits application potentials in remote sensing image, environmental monitoring, agriculture, and medical detection. − Recently, near-infrared polarization photodetectors (780–2526 nm) based on low-symmetry 2D/1D materials have become a research hotspot because the near-infrared light is not affected by smoke or clouds in the atmosphere. − To date, some narrow-bandgap 2D/1D materials have been explored as near-infrared polarization photodetectors successfully because of the anisotropic photoresponse ascribed to the low-symmetry crystal structure, such as black phosphorus (b-P), As–P, PdPS, NbS 3 , GeSe, GaAs, Te, Sb 2 S 3 , ZnTe, etc. In particular, III–V semiconductor nanowires (NWs) that are appropriate for contemporary silicon technology also have polarized photoresponse properties resulting from their anisotropic 1D geometry structure. , They display an anisotropic photoresponse for linear polarization light as long as the energy of the incident light is larger than that of the NW bandgap. ,, However, there are few reports about near-infrared polarization photodetectors based on narrow-bandgap III–V NWs.…”

Mechanical, optical, and thermoelectric properties of semiconducting ZnIn2X4 (X= S, Se, Te) monolayers

“…For the cost-effective practical applications, it is more appealing to employ 2D intrinsic semiconductors rather than the band gap opening in graphene. That is why, many 2D semiconductors have been fabricated up to now, such as: single-triazine-based g-C 3 N 4 [20], transition metal dichalcogenides family [21][22][23], phosphorene [24,25], indium selenide [26], MoSi 2 N 4 family [27], polyaniline C 3 N [28], graphene-like BC 2 N [29], nickel diazenide NiN 2 [30], niobium oxide diiodide NbOI 2 [31], and most recently penta-PdPS [32] and PdPSe [33] nanosheets.…”