Energy efficient LEDs and lasers with Chalcogenide monolayers

<sub>2</sub> (orange) on top of MoS<sub>2</sub> (blue). The SPEEM-microscopy reveals coupling between both layers and charge transfer.

2 (orange) on top of MoS2 (blue). The SPEEM-microscopy reveals coupling between both layers and charge transfer. © F. Kronast/HZB

As reported by nanotechweb.org, monolayers of certain chalcogenides might be used to make energy-efficient nano-optoelectronics devices, such as LEDs, lasers, solar cells, and high-electron-mobility transistors. Scientists of the University of California at Berkeley, the Lawrence Berkeley National Lab and the Helmholtz-Zentrum Berlin für Materialien und Energie in Berlin investigated the electronic and optoelectronic properties of a so called heterojunction of WSe2/MoS2.

“At BESSY II we performed local x-ray photoemission spectroscopy at the SPEEM microscope and could observe interlayer coupling and charge transfer in this new type of heterojunction”, Dr. Florian Kronast, HZB, explains. This makes these types of heterojunctions interesting candidates for new devices.

To the article in nanotechweb

The present work is detailed in PNAS doi: 10.1073/pnas.1405435111.

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