Two-dimensional (2D) MoS 2 has received much research interest because of its outstanding optical and electronic characteristics and is regarded as one of the most prospective semiconductors for application in future optoelectronic devices. Nevertheless, the low visible light absorption capacity and the long photoresponse time restrict its practical application in the field of photodetectors. Therefore, optoelectronic performance of 2D MoS 2 needs to be further improved. In this study, a MoS 2 flake modified by double-layered Au nanoparticles (NPs) with sandwich structure (Au−MoS 2 −Au) photodetector is designed and fabricated for the sensitive detection of visible light. Benefiting from the enhanced local surface plasmon resonance (LSPR) coupling between the upper and lower layers of Au NPs deposited on both sides of few-layered MoS 2 , double-layered Au NPs with sandwich structure is able to enhance visible light absorption and local electric field of MoS 2 . Accordingly, the optoelectronic performance of the Au−MoS 2 −Au photodetector is superior to that of MoS 2 modified with single-layered Au NPs. The peak photoresponsivity and specific detectivity of the Au−MoS 2 −Au photodetector are as high as 1757 A/W and 3.44 × 10 10 Jones, respectively. The response speed is estimated to be less than 24 ms. The present research may contribute to the development of a promising approach toward the design and fabrication of high-performance devices via LSPR coupling of double-layered metal NPs with sandwich structure.

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As a rapidly growing family of 2D transition metal carbides and nitrides, MXenes are recognized as promising materials for the development of future electronics and optoelectronics. So far, the reported patterning methods for MXene films lack efficiency, resolution, and compatibility, resulting in limited device integration and performance. Here, a high‐performance MXene image sensor array fabricated by a wafer‐scale combination patterning method of an MXene film is reported. This method combines MXene centrifugation, spin‐coating, photolithography, and dry‐etching and is highly compatible with mainstream semiconductor processing, with a resolution up to 2 µm, which is at least 100 times higher than other large‐area patterning methods reported previously. As a result, a high‐density integrated array of 1024‐pixel Ti3C2Tx/Si photodetectors with a detectivity of 7.73 × 1014 Jones and a light–dark current ratio (Ilight/Idark) of 6.22 × 106, which is the ultrahigh value among all reported MXene‐based photodetectors, is fabricated. This patterning technique paves a way for large‐scale high‐performance MXetronics compatible with mainstream semiconductor processes.