Dear Sarika, unfortunately I'm not a proven expert in this field. Thus all I can do is suggest to you some potentially useful articles which migth help you in your analysis. For example, please have a look at this paper:

Quantum Dot Size Effect on the Frontier Molecular Orbital Energies in the Presence of Different Aquatic Environmental Ligands

Article Quantum Dot Size Effect on the Frontier Molecular Orbital En...

This paper is freely available as pubic full text on RG, so you can easily dowload and print out a pdf file.

I aslo strongly suggest that you search the "Publications" section of RG for other helpful references. For example, just search for the term "CdSe@ZnS quantum dots" and then click on "Publications". As you can see below, this will provide you with a long list of interesting papers which have been posted by RG member, some of them even as public full texts:

https://www.researchgate.net/search.Search.html?type=publication&query=CdSe@ZnS%20quantum%20dots

I hopw this helps. Good luck with your work and best wishes, Frank Edelmann

By using the density-functional tight binding method, we studied the electronic structure of CdSe quantum dot(QD)-buckminsterfullerene (C60) hybrid systems as a function of both the size of the QD and concentration of the fullerene molecule. the lowest unoccupied molecular orbital energy level of the hybrid CdSeQD-C60 systems lies on the fullerene moiety, whereas the highest occupied molecular orbital (HOMO) energy level lies either on the QD or the fullerene depending on size of the CdSe QD. We explored the possibility of engineering the energy level alignment by varying the size of the CdSe QD. With increase in size of the QD, the HOMO level is shifted upward and crosses the HOMO level of the C60-thiol molecule resulting transition from the type-I to type-II band energy alignment. The density of states and charge density plot support these types of band gap engineering of the CdSe-C60 hybrid systems. This type II band alignment indicates the possibility of application of this nanohybrid for photovoltaic purpose.

Dear Sarika Kumari ,

I would recommend to you perform an ultraviolet photoemission spectroscopy (UPS).

It is a technique similar to the XPS, but it reads the energy on the UV-region (negative region, where the HOMO and LUMO are located).

You can find this topic in research gate and some scientific article:

https://www.researchgate.net/post/How-to-interpret-the-UPS-spectrum-of-quantum-dots

https://www.osti.gov/pages/servlets/purl/1374971

Kind regards,

GG.

Please see following link:

https://www.youtube.com/watch?v=CMSD264DoFo