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Updated: Jan 27, 2026

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Engineering fluorescence intensity and electron concentration of monolayer MoS2 by forming heterostructures with
Qiushi Feng1, Jia Shi, Weiqiang Yang
1Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, China. wzliu@nenu.edu.cn hyxu@nenu.edu.cn.
Abstract:
In this work, novel 2D/0D hybrid heterostructures with facilely adjustable fluorescence intensity and carrier concentration are achieved by decorating monolayer MoS2 (1L-MoS2) flakes with semiconductor-dots (carbon-dots or ZnO-dots). By carbon-dot decoration, the fluorescence intensity of 1L-MoS2 is significantly suppressed due to the n-type doping effect of electron transfer from carbon-dots to 1L-MoS2. In contrast, 1L-MoS2 decorated with ZnO-dots exhibits remarkably enhanced photoluminescence, because of the effective p-type doping modulation of electron transfer from 1L-MoS2 to ZnO-dots. The different charge transfer directions lie in the distinct energy band alignment of the two heterostructures. Raman, time-resolved photoluminescence and X-ray photoelectron spectroscopy studies prove the effective charge transfer between 1L-MoS2 and carbon-dots/ZnO-dots. Semi-quantitative estimations based on a mass-action-model demonstrate that the electron concentration in 1L-MoS2 can be controllably tuned from 1012 to 1014 cm-2via the p-type/n-type doping effect of these hybrid heterostructures.
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