3 min read
A research team at UCLA’s California NanoSystems Institute (CNSI) has engineered a stretchable, printable light-emitting membrane that may transform photonic device design. The new material is constructed from alternating layers of ultrathin molybdenum disulfide (MoS₂) and the polymer Nafion, combining optoelectronic performance with structural resilience.
It emits strong light, survives stretching and deformation, and is compatible with large-scale fabrication, potentially overcoming a major barrier in integrating ultrathin semiconductors into photonic circuits. Unlike conventional electronics where signals travel as electrons, photonic devices transmit information via photons (light).
How the Light-Emitting Material Works
The membrane comprises alternating 3-atoms thick layers of 2D MoS₂ sandwiched with Nafion, a polymer more commonly associated with fuel cells. In this composite, Nafion plays multiple roles: it structurally supports the fragile 2D layers, helps heal defects, and enhances light emission efficiency by suppressing nonradiative loss paths.
The MoS₂ provides its inherent optoelectronic behavior, while Nafion ensures mechanical flexibility and resilience. Even when stretched, exposed to ambient or watery environments, or subjected to repeated deformation cycles, the membrane retains brightness and structural integrity.
Crucially, the design is scalable and printable over large areas, a must for real-world device integration. Compared to brittle, exotic semiconductors, this composite offers ease of manufacture and greater tolerance for imperfections.
Shorter-term applications include flexible displays, stretchable lasers, optical interconnects, and wearable/curved photonic systems. Because the material can conform to surfaces and endure deformation, it opens design possibilities that rigid components can’t match.
The material’s performance over repeated stretching and environmental exposure (e.g. air, moisture) is particularly promising, suggesting real-world robustness.
In press material from UCLA’s Newsroom, researchers emphasize that the composite enables “orders of magnitude greater light-emitting efficiency” compared to bare 2D materials, largely thanks to Nafion’s defect passivation.
Challenges and Risks
While the breakthrough is exciting, several technical and engineering challenges remain:
- Uniformity and scale: Ensuring consistent light emission across large areas, especially in real devices, will be nontrivial.
- Interface quality: The interfaces between MoS₂ and Nafion must be carefully controlled to avoid losses and degradation.
- Durability under stress: Long-term reliability under repeated mechanical stretching, bending, and environmental stress is yet to be fully proven.
- Integration with existing platforms: Bridging this new membrane into standard semiconductor or photonic manufacturing pipelines poses compatibility challenges.
- Cost and standardization: Before commercialization, metrics like lifetime, yield, and cost need standardization and optimization.
Still, the research team has already filed a patent for the technology, signaling confidence in its potential for practical adoption.
The UCLA team is multidisciplinary, bringing together 2D semiconductor and polymer chemistry expertise, which allowed them to combine materials from two traditionally separate domains. This cross-field synergy was critical to the discovery.
