Gold-Autocatalyzed Synthesis of Multi-Element Clusters on Monolayer MoS₂ for the Manipulation of Photogenerated Carriers

For optoelectronic materials, the ability to detect light in a broad wavelength range is critical for practical applications and commercialization. According to previous studies of photodetectors based on monolayer MoS₂, manipulation of photogenerated carriers and broadband photodetection are exceedingly difficult. Herein, a rapid and mild gold-autocatalyzed synthesis method is developed to fabricate multi-element clusters (MECs) on monolayer MoS₂ at room temperature to obtain a composite with radically modified properties. MECs can modulate the photogenerated carrier behavior and the electronic structure of MoS₂. Therefore, MECs/MoS₂ exhibit a broadband photodetection range from 532 to 1550 nm (visible light-near infrared), which is far beyond the bandgap limit of monolayer MoS₂ (1.8 eV, cut-off wavelength of about 690 nm), as well as rapid response/recovery processes (41.0/134.4 ms) and a reduced dark current. The strategy overcomes the high-temperature requirment to mix multiple elements and offers new opportunities for monolayer MoS₂ to become a promising material for next-generation broadband optoelectronic devices.