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Highly Efficient Dual-Gated Light-Emitting Diodes Based on Suspended Monolayer WSe2.
Zhenliang Hu1,2, Weiqiao Xia2, Qiang Fu1,2
1School of Electronic Science and Engineering, Southeast University, Nanjing 210096, P. R. China.
Nano Letters
|December 19, 2025
Summary
Suspended transition metal dichalcogenides (TMDCs) offer superior light emission for novel LEDs. This study demonstrates high efficiency in suspended WSe2-based devices, paving the way for advanced on-chip light sources.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Transition Metal Dichalcogenides (TMDCs) exhibit unique optoelectronic properties.
- Suspended TMDCs show higher emission efficiency due to reduced quenching effects compared to supported films.
- Applications of suspended TMDCs in light-emitting diodes (LEDs) are underexplored.
Purpose of the Study:
- To design and fabricate dual-gated P-S(suspended)-N LEDs utilizing bipolar monolayer WSe2.
- To investigate the optoelectronic performance of suspended WSe2 in LED devices.
- To demonstrate the potential of suspended TMDCs for efficient on-chip light sources.
Main Methods:
- Fabrication of dual-gated LEDs using suspended monolayer WSe2.
- Photoluminescence Quantum Yield (PLQY) measurements for suspended and supported WSe2 flakes.
- Electroluminescence (EL) characterization of the fabricated P-S-N junction LEDs.
Main Results:
- Suspended WSe2 achieved a PLQY of ~28.8%, over 5 times higher than supported flakes.
- Electrostatically defined P-S-N junctions in suspended WSe2 LEDs exhibited bright EL.
- Maximal external quantum efficiency (EQE) reached ~4.2% at room temperature, significantly outperforming P-I-N junctions.
Conclusions:
- Suspended WSe2 demonstrates significantly enhanced PLQY due to the absence of substrate-induced defects.
- The fabricated suspended WSe2 LEDs show promising high EL performance.
- Suspended TMDCs are a viable platform for developing efficient on-chip light-emitting devices.
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