Abstract
During the last few years, intensive research has been carried out on the synthesis of different hybrid nanostructures mostly using hydrothermal and solvothermal techniques. But the fabrication of the hybrid nanostructure through surface charge interaction of the individual components is comparatively less explored. Here in this work, a hybrid nanostructure based on MoS2 and CdTe quantum dots is synthesized through a simple surface charge interaction process using the negative surface charge of the excess sulfide ions (S2-) present at the edge of the MoS2 QDs and positively charged CdTe QDs where the positive surface charge was induced in CdTe by using a cysteamine ligand in acidic medium. In the photoluminescence (PL) emission spectrum, a new peak is observed which is different from those of both of the individual components. Interestingly, with increasing the concentration of CdTe QDs during the preparation of the hybrid nano-structure, the peak of hybrid QDs is gradually blue shifted towards the emission of MoS2 QDs. The maximum blue shift occurs up to 1:1 (v/v) ratio of MoS2:CdTe as in this concentration ratio all S2- ions are neutralized by -NH3+. This new emission occurs from a newly generated hybrid energy level. The energy level positions of the two different QDs along with the hybrid ones are estimated via cyclic voltammetry and absorption experiments.
| Original language | English |
|---|---|
| Pages (from-to) | 1853-1863 |
| Number of pages | 11 |
| Journal | Nanoscale Advances |
| Volume | 1 |
| Issue number | 5 |
| DOIs | |
| State | Published - 15 May 2019 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2019 The Royal Society of Chemistry.
Funding
A new kind of hybrid nano-structure is synthesized via surface charge interaction of two oppositely charged QDs. Here we have used negatively charged MoS2 QDs and positively charged CdTe QDs. As a result, a new emission peak is observed for the hybrid nano-structure which is different from those of both of the individual QDs. Moreover the excitation wavelength for the hybrid nanostructure is found to be 360 nm which is signi-cantly different to the excitation wavelengths of the individual D. H. acknowledges the Council of Scientic and Industrial Research (CSIR), New Delhi, for awarding fellowship, S. B. acknowledges the Indian Association for the Cultivation of Science (IACS) for awarding her fellowship, A. G. acknowledges DST-SERB for his fellowship and S. K. S. acknowledges IACS for infrastructural facilities and the Department of Science and Technology (DST), New Delhi, Government of India, for nan-cial support. We would like to acknowledge Mr Rajib Pramanick for his generous help in the CV study and Mr Manoranjan Bar for his generous help in the TCSPC study.
| Funders | Funder number |
|---|---|
| Council of Scientic and Industrial Research | |
| DST-SERB | |
| Department of Science and Technology | |
| Indian Association for the Cultivation of Science | |
| Council of Scientific and Industrial Research, India |