Self-Powered Visible–Invisible Multiband Detection and Imaging Achieved Using High-Performance 2D MoTe₂/MoS₂ Semivertical Heterojunction Photodiodes

Abstract

Two-dimensional (2D) van der Waals (vdW) heterostructures herald new opportunities for conducting fundamental studies of new physical/chemical phenomena and developing diverse nanodevice applications. In particular, vdW heterojunction p−n diodes exhibit great potential as highperformance photodetectors, which play a key role in many optoelectronic applications. Here, we report on 2D MoTe 2 /MoS 2 multilayer semivertical vdW heterojunction p−n diodes and their optoelectronic application in self-powered visible−invisible multiband detection and imaging. Our MoTe 2 /MoS 2 p−n diode exhibits an excellent electrical performance with an ideality factor of less than 1.5 and a high rectification (ON/OFF) ratio of more than 10 4 . In addition, the photodiode exhibits broad spectral photodetection capability over the range from violet (405 nm) to near-infrared (1310 nm) wavelengths and a remarkable linear dynamic range of 130 dB within an optical power density range of 10 −5 to 1 W/cm 2 in the photovoltaic mode. Together with these favorable static photoresponses and electrical behaviors, very fast photo-and electrical switching behaviors are clearly observed with negligible changes at modulation frequencies greater than 100 kHz. In particular, inspired by the photoswitching results for periodic red (638 nm) and near-infrared (1310 nm) illumination at 100 kHz, we successfully demonstrate a prototype self-powered visible− invisible multiband image sensor based on the MoTe 2 /MoS 2 p−n photodiode as a pixel. Our findings can pave the way for more advanced developments in optoelectronic systems based on 2D vdW heterostructures.

2D WS2 Based Asymmetric Schottky Photodetector with High Performance

“…[ 11–15 ] Noticeably, TMDs such as MoS 2 , WS 2 , MoSe 2 and WSe 2 possessing a moderate band gap range of 1.3–2.0 eV and smooth surface can be artificially stacked to form van der Waals heterostructures. [ 15 ] Therefore, a breaking number of novel 2D TMDs and other layered material hetero‐structure (such as MoTe 2 /MoS 2 , [ 16 ] WS 2 /MoS 2 [ 17 ] ) based self‐driven photodetectors because of photovoltaic effect are studied in these years. [ 18–21 ] By contrast, ambipolar WSe 2 , BP, and unipolar MoS 2 lateral or vertical homostructure comprised of P and N‐type doping part can be achieved through the local split gates, surface chemical doping and thickness engineering.…”

Recent Progress in Short‐ to Long‐Wave Infrared Photodetection Using 2D Materials and Heterostructures

“…Furthermore, the photodiode delivers a V oc of 0.3-0.4V in the NIR region due to the vdW bandgap of 0.67 eV. [250] Lee et al have demonstrated a multifunctional electronic device composed of SnSe 2 /MoTe 2 heterostructures with type-III band alignment (broken band alignment), which is different from the reports mentioned earlier (that are mostly based on type-II band alignment). With the calculated junction barrier of 1.4 eV, the device responds well to the 811 nm laser and exhibits detectivity of 7.5 × 10 12 Jones, in which the photocurrent is a result of FN tunneling caused by the interband transitions.…”

“…Furthermore, the photodiode delivers a V oc of 0.3–0.4V in the NIR region due to the vdW bandgap of 0.67 eV. [ 250 ] Lee et al. have demonstrated a multifunctional electronic device composed of SnSe 2 /MoTe 2 heterostructures with type‐III band alignment (broken band alignment), which is different from the reports mentioned earlier (that are mostly based on type‐II band alignment).…”

2D van der Waals Heterojunction Nanophotonic Devices: From Fabrication to Performance

“…Ahn et al reported the optoelectronic application of a 2D MoTe 2 /MoS 2 2D vdWh with a wide spectrum detector (see Figure 7). [81] The developed MoTe 2 /MoS 2 photodiode exhibited wide spectrum photoelectric detection at wavelengths of 405-1310 nm, with a significant linear dynamic range of 130 dB in the range of 10% optical power density and 5 to 1 W cm −2 in photovoltaic mode.…”