Three- and Two-Photon NIR-to-Vis (Yb,Er) Upconversion from ALD/MLD-Fabricated Molecular Hybrid Thin Films

: Zivile Giedraityte, Minnea Tuomisto, Mika Lastusaari, Maarit Karppinen

Publisher: AMER CHEMICAL SOC

: 2018

: ACS Applied Materials and Interfaces

: ACS APPLIED MATERIALS & INTERFACES

: ACS APPL MATER INTER

: 10

: 8845

: 8852

: 8

: 1944-8244

: 1944-8252

DOI: https://doi.org/10.1021/acsami.7b19303

We report blue, green, and red upconversion emissions with strongly angular-dependent intensities for a new type of hybrid (Y,Yb,Er) pyrazine thin films realized using the atomic/molecular layer deposition thin-film fabrication technology. The luminescence emissions in our amorphous (Y,Yb,Er) pyrazine thin films of a controllable nanothickness originate from three- and two-photon NIR-to-vis excitation processes. In addition to shielding the lanthanide ions from nonradiative de-excitation, the network of interconnected organic molecules serves as an excellent matrix for the Yb3+-to-Er3+ excitation energy transfer. This suggests a new approach to achieve efficient upconverting molecular materials with the potential to be used for next-generation medical diagnostics, waveguides, and surface-sensitive detectors.