Sebek, Matej;
Wu, Gang;
Wang, Zeng;
Sullivan, Michael;
Seng, Debbie Hwee Leng;
Su, Xiao Di;
Thanh, Nguyen Thi Kim;
(2025)
Greatly Enhanced Radiative Recombination at High Exciton Density in Acid-Treated 2D Alloy.
ACS Applied Materials & Interfaces
, 17
(18)
pp. 26845-26853.
10.1021/acsami.4c18618.
![[thumbnail of tfsi_AMI_review_final_2.pdf]](https://discovery.ucl.ac.uk/style/images/fileicons/text.png) |
Text
tfsi_AMI_review_final_2.pdf - Accepted Version Access restricted to UCL open access staff until 24 April 2026. Download (2MB) |
Abstract
Enhanced photoluminescence (PL) in transition metal dichalcogenides (TMDs) is critical for their application in optoelectronics. In this study, we report a 99 × PL enhancement in a superacid bis(trifluoromethane) sulfonimide (TFSI)-treated MoS2(1–x)Se2x alloy. The alloy’s optical bandgap is tunable by changing its stoichiometry, allowing for PL enhancement at tailored positions. The PL enhancement is robust even at high excitation power, overcoming the limitation of exciton–exciton annihilation observed in MoS2. Through molecular dynamics simulations and spectroscopic analysis, we demonstrate that the MoS2(1–x)Se2x monolayer inherently exhibits moderate strain, which shifts the van Hove singularity in the S-rich domain. Furthermore, density functional theory calculations reveal the absence of a pronounced van Hove feature in the alloy configuration. Our findings extend the range of materials amenable to superacid treatment and open new avenues for optoelectronic applications, particularly those requiring high excitation powers.
| Type: | Article |
|---|---|
| Title: | Greatly Enhanced Radiative Recombination at High Exciton Density in Acid-Treated 2D Alloy |
| Location: | United States |
| DOI: | 10.1021/acsami.4c18618 |
| Publisher version: | https://doi.org/10.1021/acsami.4c18618 |
| Language: | English |
| Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | Photoluminescence enhancement; MoS2(1−x)Se2x alloy; superacid TFSI treatment; high excitation power; strain |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10211900 |
Archive Staff Only
 |
View Item |
