Fractional Contributions of Defect‐Originated Photoluminescence from CuInS 2 /ZnS Coreshells for Hybrid White LEDs

• Published in: Journal of nanomaterials 2014-12, Vol.2014 (1)
• Main Authors: Rice, Quinton, Raut, Sangram, Chib, Rahul, Gryczynski, Zygmunt, Gryczynski, Ignacy, Zhang, Wenjin, Zhong, Xinhua, Abdel-Fattah, Mahmoud, Tabibi, Bagher, Seo, Jaetae
• Format: Article
• Language: English
• ISSN: 1687-4110; 1687-4129
• DOI: 10.1155/2014/979875

The wide optical tunability and broad spectral distribution of CuInS 2 /ZnS (CIS/ZnS) coreshells are key elements for developing the hybrid white light emitting diodes where the nanoparticles are stacked on the blue LEDs. Two CIS/ZnS 555 nm and CIS/ZnS 665 nm coreshells are utilized for the hybrid white LED development. The time‐resolved spectroscopy of CIS/ZnS 555 nm and CIS/ZnS 665 nm reveals the correlation between the fast, intermediate, and slow decay components and the interface‐trapped state and shallow‐ and deep‐trapped states, although the fractional amplitudes of photoluminescence (PL) decay components are widely distributed throughout the entire spectra. The temperature‐resolved spectroscopy explains that the PL from deep‐trapped donor‐acceptor (DA) state has relatively large thermal quenching, due to the relative Coulomb interaction of DA pairs, compared to the thermal quenching of PL from interface defect state and shallow‐trapped DA state. A good spectral coupling between the blue diode excitation and the PL from CIS/ZnS leads to the realization of hybrid white LEDs.