2D MXenes for Hot‐Carrier Photodetection. Issue 20 (17th July 2022)

• Record Type: Journal Article
• Authors: Liu, Tingting; Zhang, Cheng; Li, Xiaofeng
• Is Part Of: Advanced optical materials. Volume 10:Issue 20(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-17
• Subjects: hot carriers -- MXenes -- photodetectors -- strain engineering; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.202201153
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: For 2D MXenes (Mo2 C and Ti3 C2 ), the fundamental hot‐carrier‐related processes are studied by using the first‐principles calculation, including the material electronic structures, indirect/direct transitions for hot‐carrier generation, electron–electron and electron–phonon scatterings during hot‐carrier transport, and electronic modulation on material to evaluate the potentials of 2D MXenes in hot‐carrier photodetection. It is found that Mo2 C and Ti3 C2 show higher hot‐carrier generation efficiencies than Au in energy over 1 eV, especially for Mo2 C, which shows better transport performance than Ti3 C2 . Biaxial strain to adjust the electronic structure of Mo2 C is further used to optimize the hot‐carrier transport properties. A Mo2 C/MoGeSiN4 hot‐electron photodetector is proposed, which shows that the compressive strain (−4%) on Mo2 C material enables a twofold enhancement of the quantum efficiency and responsivity. The Monte Carlo device simulation predicts an extremely high responsivity up ≈176 mA W −1 at the communication wavelength of 1550 nm, which is one order of magnitude over the existing hot‐carrier devices and can be competitive with the existing semiconductor‐based photodetectors. Abstract : A Mo2 C/MoGeSiN4 hot‐electron photodetector is proposed. A comprehensive study combining hot‐carrier dynamics by first‐principles calculations and the overall responses of Mo2 C/MoGeSiN4 hot‐carrier device by Monte Carlo simulation provide a promising advancement for the hot‐carrier photodetectors of MXenes.