5 years ago

Role of Core–Shell Formation in Exciton Confinement Relaxation in Dithiocarbamate-Capped CdSe QDs

Role of Core–Shell Formation in Exciton Confinement Relaxation in Dithiocarbamate-Capped CdSe QDs
Sandeep Verma, Sreejith Kaniyankandy
The possibility of exciton delocalization in alkyldithiocarbamate (ATC)-capped CdSe has been investigated for several alkyl groups and compared with phenyldithiocarbamates (PTCs). We find a bathochromic shift for ATC similar to the one obtained for PTC. Our computational studies show reduction in HOMO–LUMO gaps in both PTC and ATC, albeit with a lower shift. However, TDDFT studies revealed that ATC-capped CdSe is more of a localized HOMO state as compared with partly delocalized HOMO in PTC-capped CdSe, hinting at a difference in electronic interaction between the two binding groups. We hypothesized the formation of sulfide layer over the CdSe QDs as the possible reason for the observed bathochromic shift, as verified by absorption spectra of S2– ligand exchange samples. The formation of CdS shell leads to substantial electron delocalization because CdSe CB is in close resonance with CdS, which is exactly the opposite of what was previously concluded in the literature.

Publisher URL: http://dx.doi.org/10.1021/acs.jpclett.7b01259

DOI: 10.1021/acs.jpclett.7b01259

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.