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DOE OSTI · 3010319

Tailoring optical response of MXene thin films

Simon, Jeffrey [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000289837055)·Choi, Kyu Ri [Purdue University, West Lafayette, IN (United States); Chungbuk National University (Korea, Republic of)]·Ippolito, Stefano [Drexel University, Philadelphia, PA (United States)] (ORCID:0000000269063961)·Prokopeva, Ludmila [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000349677461)·Fruhling, Colton [Purdue University, West Lafayette, IN (United States)]·Shalaev, Vladimir M. [Purdue University, West Lafayette, IN (United States)]·Kildishev, Alexander V. [Purdue University, West Lafayette, IN (United States)]·Gogotsi, Yury [Drexel University, Philadelphia, PA (United States)]·Boltasseva, Alexandra [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000189052605)
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Abstract

Due to their attractive optical properties, 2D MXenes have garnered interest in nanophotonic and optoelectronic applications. However, tuning their properties typically requires the iterative synthesis of MXenes with a specific set of properties, such as the absorption band position, electronic conductivity, and dielectric constant. We demonstrate how to tailor the optical properties of MXene thin films over a broad 1500-nm wavelength range by mixing different ratios of highly conductive Ti 3 C 2 T x with poorly conductive Nb 2 CT x . By changing the MXene film composition, the epsilon-near-zero (ENZ) point, where the optical properties transit from dielectric to metallic, was varied in the spectral range from 1.1 to 2.6 µm. Additionally, we observed a reduction in absorption in some compositions compared to the absorption of the pure MXene films. Compared to other methods, this approach enables simple and continual tuning of MXene optical properties without requiring multiple time-consuming synthesis steps.

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2D materialsENZ propertiesMXenesoptical tunabilityplasmonicssolution processing

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Simon, Jeffrey [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000289837055), Choi, Kyu Ri [Purdue University, West Lafayette, IN (United States); Chungbuk National University (Korea, Republic of)], Ippolito, Stefano [Drexel University, Philadelphia, PA (United States)] (ORCID:0000000269063961), Prokopeva, Ludmila [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000349677461), Fruhling, Colton [Purdue University, West Lafayette, IN (United States)], Shalaev, Vladimir M. [Purdue University, West Lafayette, IN (United States)], Kildishev, Alexander V. [Purdue University, West Lafayette, IN (United States)], Gogotsi, Yury [Drexel University, Philadelphia, PA (United States)], Boltasseva, Alexandra [Purdue University, West Lafayette, IN (United States)] (ORCID:0000000189052605). 2025-04-03. Tailoring optical response of MXene thin films. https://doi.org/10.1515/nanoph-2024-0769

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