TY - JOUR
T1 - Novel hetero-layered materials with tunable direct band gaps by sandwiching different metal disulfides and diselenides
AU - Terrones, Humberto
AU - López-Urías, Florentino
AU - Terrones, Mauricio
N1 - Funding Information:
This work is supported by the U.S. Army Research Office MURI grant W911NF-11-1-0362. Supported in part by the Materials Research Computing and Cyberinfrastructure unit of Information Technology Services and Penn-State Center for Nanoscale Science. M.T. also acknowledges support from the Penn State Center for Nanoscale Science for seed grant on 2-D Layered Materials (DMR-0820404).
PY - 2013
Y1 - 2013
N2 - Although bulk hexagonal phases of layered semiconducting transition metal dichalcogenides (STMD) such as MoS2, WS2, WSe2 and MoSe2 exhibit indirect band gaps, a mono-layer of STMD possesses a direct band gap which could be used in the construction of novel optoelectronic devices, catalysts, sensors and valleytronic components. Unfortunately, the direct band gap only occurs for mono-layered STMD. We have found, using first principles calculations, that by alternating individual layers of different STMD (MoS2, WS2, WSe2 and MoSe2) with particular stackings, it is possible to generate direct band gap bi-layers ranging from 0.79 eV to 1.157 eV. Interestingly, in this direct band gap, electrons and holes are physically separated and localized in different layers. We foresee that the alternation of different STMD would result in the fabrication of materials with unprecedented optical and physico-chemical properties that would need further experimental and theoretical investigations.
AB - Although bulk hexagonal phases of layered semiconducting transition metal dichalcogenides (STMD) such as MoS2, WS2, WSe2 and MoSe2 exhibit indirect band gaps, a mono-layer of STMD possesses a direct band gap which could be used in the construction of novel optoelectronic devices, catalysts, sensors and valleytronic components. Unfortunately, the direct band gap only occurs for mono-layered STMD. We have found, using first principles calculations, that by alternating individual layers of different STMD (MoS2, WS2, WSe2 and MoSe2) with particular stackings, it is possible to generate direct band gap bi-layers ranging from 0.79 eV to 1.157 eV. Interestingly, in this direct band gap, electrons and holes are physically separated and localized in different layers. We foresee that the alternation of different STMD would result in the fabrication of materials with unprecedented optical and physico-chemical properties that would need further experimental and theoretical investigations.
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U2 - 10.1038/srep01549
DO - 10.1038/srep01549
M3 - Article
C2 - 23528957
AN - SCOPUS:84875773096
SN - 2045-2322
VL - 3
JO - Scientific reports
JF - Scientific reports
M1 - 1549
ER -