Synthesis, structure and excitation wavelength dependent PL properties of novel nanocomposite La2O2CO3·CuO·ZnO

•Novel nanocomposite, La2O2CO3·CuO·ZnO was synthesized and characterized.•PL behavior of La2O2CO3·CuO·ZnO is excitation wavelength dependent.•The PL property is contrary to Kasha’s rule of excitation wavelength dependence.•UV, blue emissions are detected at 324–397 and 408–488 nm.•Green and red emissions are observed at 500–592 and 676 nm.

A novel multi-metal nanocomposite, La2O2CO3·CuO·ZnO has been synthesized by co-precipitation method and characterized by XRD, SEM, EDS and PL spectra. XRD showed the presence of La2O2CO3, CuO and ZnO phases with an average particle size of 20 nm. Excitation at different wavelengths showed PL in UV and visible regions. Excitation at 220–270 nm provided UV emissions. Excitations at 298, 324 and 355 nm showed PL in the violet and blue regions. Excitation at 395 and 450 nm provided green and red luminescence, respectively. It has been found that PL behavior of La2O2CO3·CuO·ZnO is excitation wavelength dependent. This PL property is contrary to well-known Kasha’s rule of excitation wavelength dependence of emission spectrum. The excitation peaks at 300–325 (broad band), 353, 371, 394, 408 nm were observed when monitored at 450 nm.

Graphical abstractPL spectra of La2O2CO3·CuO·ZnO at 298 nm (), 324 nm () and 355 nm (), 395 nm () and 450 nm ().Figure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slide