Enhancing Nonradiative Energy Transfer between Nitridized Carbon Quantum Dots and Monolayer WS₂

Abstract

Two-dimensional (2D) monolayer (1L) transition metal dichalcogenides (TMDs) suffer from low absorption in the visible light region. Nonradiative energy transfer (NRET) is an effective method to enhance such absorption, which, as shown in this study, can be accomplished by using surface nitridized carbon quantum dots (CQDs). The optical absorption and photoluminescence (PL) of CQDs in the visible light region can be greatly enhanced by increasing the level of nitridization. The nitridized CQDs exhibit weak p-type doping but strong PL quenching in contact with vapor transport (VT)-deposited 1L-WS2. Owing to the good overlap between the fluorescence and absorption spectra for CQDs and 1L-WS2, an interactive NRET process reduces the PL lifetimes of both CQDs and 1L-WS2. The NRET efficiency can be greatly enhanced by up to 73% for samples coated with CQDs of increasing surface nitridization.

Electrochemiluminescence Sensor Based on N-Doped Carbon Quantum Dots for Determination of Ceftazidime in Real Samples

“…Characterization of CQDs.-The N-CQDs were synthesized according to previous reports with small modification. 34 The product was characterized using different techniques; the results are described below.…”

Transient Absorption Analysis on Energy Transfer from Carbon Quantum Dots to Tungsten Disulfide

“…23 By increasing the degree of carbon QDs (CQDs) nitriding, the nonradiative energy transfer efficiency between CQDs and monolayer tungsten disulfide (WS 2 ) would be greatly enhanced 73%. 24 By varying the size of QDs, electron transfer rate between PbS/ CdS QDs and MoS 2 had been tuned. 25 CdSe QDs charge transferred to monolayer WS 2 and improved the PL performance of monolayer WS 2 .…”

“…Cotlet’s group had reported that nonradiative energy transfer rate would be increased from individual CdSe/ZnS QDs to SnS 2 with added number of 2D material layers . By increasing the degree of carbon QDs (CQDs) nitriding, the nonradiative energy transfer efficiency between CQDs and monolayer tungsten disulfide (WS 2 ) would be greatly enhanced 73% . By varying the size of QDs, electron transfer rate between PbS/CdS QDs and MoS 2 had been tuned .…”