Synthesis of upconverting nanosheets derived from Er-Yb and Tm-Yb Co-doped layered perovskites and their layer-by-layer assembled films

Gunay, Bensu
Süer, Özge
Döğer, Hilal
Arslan, Özlem
Unal, Ugur
Sağlam, Özge
© 2022 Elsevier B.V.Here, we investigated the structure and upconversion (UC) properties of new-type of single oxide nanosheets, derived from the Er3+/Yb3+ and Tm3+/Yb3+ co-doped Ruddlesden-Popper type layered perovskites, and their layer-by-layer (LBL) self-assembled nanofilms. The single oxide nanosheets, obtained by exfoliation of the proton-exchanged K2La2Ti3O10, had the thickness in the range of 2–3 nm indicating good consistency with the theoretical thickness and lateral size from 500 nm up to 2 µm. Er3+/Yb3+, Tm3+/Yb3+ and Tm3+/Er3+co-doped nanosheets were used as building blocks of the multilayer films deposited by layer-by-layer procedure. The LBL films composed of 2.5 % Er3+ + 5 % Yb3+, 2.5 % Tm3+ + 20 % Yb3+, 2.5 % Tm3+ + 20 % Er3+ after 60 sequences have shown a white emission confirmed by the CIE chromaticity diagram. The possible UC energy transfer of LBL films fabricated after 30 sequences using the nanosheets derived from the 2.5 % Er3+ + 5 % Yb3+ co-doped layered perovskites was also suggested. The number of photons participating in the UC process was confirmed as two-photon for both green and red UC emissions due to the 4F9/2 →4I15/2 and 2H11/2, 4S3/2→ 4I15/2 transitions, respectively.
Colloids and Surfaces A: Physicochemical and Engineering Aspects


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Citation Formats
B. Gunay, Ö. Süer, H. Döğer, Ö. Arslan, U. Unal, and Ö. Sağlam, “Synthesis of upconverting nanosheets derived from Er-Yb and Tm-Yb Co-doped layered perovskites and their layer-by-layer assembled films,” Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol. 649, pp. 0–0, 2022, Accessed: 00, 2022. [Online]. Available: