Utilize the attached figure to answer the following questions: The absorption and emission spectra of CdTe nanocrystals
Question:
Utilize the attached figure to answer the following questions:
The absorption and emission spectra of CdTe nanocrystals ranging in diameter from 2.9 to 14.8 nm are presented in the attached Figure CdTe is a direct band gap semiconductor material with a bulk band gap of 1.56 eV and an exciton Bohr radius of 7.3 nm.
(a) How do you explain the size dependent spectral shift observed in the optical spectra?
(b) Explain the spectral changes observed in the absorption spectra of the nanocrystals as their size is reduced.
(c) What emission wavelength do you expect for CdTe nanocrystals with 3.7 nm in diameter?
(d) How large is the band gap of a 30 nm diameter CdTe nanocrystal?
(e) Do you expect that optical spectroscopy would remain an useful technique to follow the growth of CdTe nanocrystals in the 20–40 nm diameter range? Justify your answer.
Financial and Managerial Accounting the basis for business decisions
ISBN: 978-0078111044
16th edition
Authors: Jan Williams, Susan Haka, Mark Bettner, Joseph Carcello