Enhanced Photocatalytic Properties of Restacked Unilamellar [SrTa2O7]2- Nanosheets of Aurivillius Phase Layered Perovskites

Mohammadreza Khodabakhsh; Bengisu Yilmaz; Sadegh Firoozi; Davoud Fatmehsari Haghshenas; Ugur Unal

doi:10.1021/acsomega.3c00593

Enhanced Photocatalytic Properties of Restacked Unilamellar [SrTa₂O₇]^2- Nanosheets of Aurivillius Phase Layered Perovskites

ACS Omega. 2023 Mar 9;8(11):10607-10617. doi: 10.1021/acsomega.3c00593. eCollection 2023 Mar 21.

Authors

Mohammadreza Khodabakhsh¹, Bengisu Yilmaz^{2

3}, Sadegh Firoozi⁴, Davoud Fatmehsari Haghshenas⁴, Ugur Unal^{1

5

2

3}

Affiliations

¹ Chemistry Department, Koc University, Rumelifeneri yolu, Sariyer, 34450 Istanbul, Turkey.
² Koc University Tupras Energy Center (KUTEM), Koc University, Rumelifeneri yolu, Sariyer, 34450 Istanbul, Turkey.
³ Materials Science and Engineering Department, Koc University, Rumelifeneri yolu, Sariyer, 34450 Istanbul, Turkey.
⁴ Department of Materials and Metallurgical Engineering, Amirkabir University of Technology, No. 350, Hafez Ave, Valiasr Square, 1591634311 Tehran, Iran.
⁵ Koc University Surface Science and Technology Center (KUYTAM), Koc University, Rumelifeneri yolu, Sariyer, 34450 Istanbul, Turkey.

Abstract

In the present work, unilamellar [SrTa₂O₇]^2- perovskite nanosheets with variable lateral dimensions were synthesized via a high-yield, three-step liquid exfoliation route from layered Bi₂SrTa₂O₉. The photocatalytic activity of the parent and exfoliated layered perovskites was evaluated for the photocatalytic dye degradation of Rhodamine B under UV light (254 nm) and reduction of water to H₂ under the full solar spectrum. A comparative study of the photocatalytic behavior of unilamellar [SrTa₂O₇]^2- perovskite nanosheets and parent layered structure showed a significant improvement in both hydrogen evolution (98.20 vs 3 μmol g^-1) and Rhodamine B degradation time (180 vs 30 min), with the restacked nanosheets. The exfoliation of layered perovskites not only increases their specific surface area, providing more active sites, but also reduces the recombination probability of electrons and holes due to their unilamellar structure and reduced charge transport pathways. The synthesis and preparation of strong acid solids such as [SrTa₂O₇]^2- perovskite nanosheets can be a promising approach for effective adsorption of pollutants with cationic nature and more efficient electron transfer between the dye and catalyst. Finally, the photocatalytic characteristics of the restacked unilamellar [SrTa₂O₇]^2- nanosheets remained unchanged after three successive cycles of recycling-reusing.