Erbium‐Doped WS₂ with Down‐ and Up‐Conversion Photoluminescence Integrated on Silicon for Heterojunction Infrared Photodetection

Abstract

The integration of 2D nanomaterials with silicon is expected to enrich the applications of 2D functional nanomaterials and pave the way for next‐generation, nanoscale optoelectronics with enhanced performances. Herein, a strategy for rare earth element doping is utilized for the synthesis of 2D WS2:Er nanosheets to achieve up‐conversion and down‐conversion emissions ranging from visible to near‐infrared regions. Moreover, the potential integration of the synthesized 2D nanosheets in silicon platforms is demonstrated by the realization of an infrared photodetector based on a WS2:Er/Si heterojunction. These devices operate at room temperature and show a high photoresponsivity of ≈39.8 mA W−1 (at 980 nm) and a detectivity of 2.79 × 1010 cm Hz1/2 W−1. Moreover, the dark current and noise power density are suppressed effectively by van der Waals‐assisted p–n heterojunction. This work fundamentally contributes to establishing infrared detection by rare element doping of 2D materials in heterojunctions with Si, at the forefront of infrared 2DMs‐based photonics.

Strong Covalent Coupling in Vertically Layered SnSe2/PTAA Heterojunctions Enabled High Performance Inorganic–Organic Hybrid Photodetectors

“…The performances of the recently reported heterostructure based-PDs are summarized in Table . The key performance parameters of our SnSe 2 /PTAA hybrid PDs are comparable or superior to other heterostructured PDs. ,− Furthermore, we also fabricated SnSe 2 PDs without the annealing (H 2 Se atmosphere) process for comparison (Figure e). The photoresponse is shown in Figure f–h.…”

Flexible and Hand-Printed Photodetector Based on Mg–SnS Nanoflakes

“…These characteristics include low toxicity, high mobility, excellent electrical conductivity, and a high absorption coefficient. Additionally, TMC materials allow alloy engineering and band tunability by substitutional metal doping or forming heterostructures with other materials. − SnS, SnSe, MoS 2 , WSe 2 , MoS 2 , and ReSe 2 are just a few of the TMC materials that have been reported for use in photodetectors. − Among these TMC materials, SnS has emerged as the most prominent material for optoelectronic applications because SnS has a very high value of absorption coefficient, allowing more and more light absorbed by a material, good electrical conductivity, and a high value of mobility allowing easy flow of photogenerated charge carriers. Along with these advantages, SnS is also earth-abundant, less costly, and less toxic. − Multiple studies and publications show that substitutional metal doping changes the host material’s band structure, enhancing the material’s overall optoelectronic capabilities.…”

Vertically Oriented FeNiO Nanosheet Array for Urea and Water Electrolysis at Industrial-Scale Current Density

“…Nickel-based oxides are considered one of the most promising electrocatalysts in an alkaline media due to their outstanding activity toward anodic oxidation reactions . Various techniques can be employed to enhance the performance of the catalyst such as electronic structure modulation, defect regulation, and surface and morphology engineering. − Doping of an active element is an effective strategy to significantly boost the performance of an electrocatalyst. For instance, to activate the active sites, a high-valence modulating element could be a wise choice to obtain enhanced performance toward electrocatalytic oxidation. − The doping of Fe ions can significantly increase the electrocatalytic performance of the host material. − Recent studies have revealed that Ni-Fe-based catalysts have shown superior electrocatalytic activity.…”