TiO<sub>2</sub>/PDA Multilayer Nanocomposites with Exceptionally Sharp Large-Scale Interfaces and Nitrogen Doping Gradient
Jakub Szewczyk, Igor Iatsunskyi, Paweł Piotr Michałowski, Karol Załęski, Cassandre Lamboux, Syreina Sayegh, Elissa Makhoul, Andreu Cabot, Xingqi Chang, Mikhaël Bechelany, Emerson Coy
Abstract
High Resolution Image Download MS PowerPoint Slide The evolving field of photocatalysis requires the development of new functional materials, particularly those suitable for large-scale commercial systems. One particularly promising approach is the creation of hybrid organic/inorganic materials. Despite being extensively studied, materials such as polydopamine (PDA) and titanium oxide continue to show significant promise for use in such applications. Nitrogen-doped titanium oxide and free-standing PDA films obtained at the air/water interface are particularly interesting. This study introduces a straightforward and reproducible approach for synthesizing a novel class of large-scale multilayer nanocomposites. The method involves the alternate layering of high-quality materials at the air/water interface combined with precise atomic layer deposition techniques, resulting in a gradient nitrogen doping of titanium oxide layers with exceptionally sharp oxide/polymer interfaces. The analysis confirmed the presence of nitrogen in the interstitial and substitutional sites of the TiO 2 lattice while maintaining the 2D-like structure of the PDA films. These chemical and structural characteristics translate into a reduction of the band gap by over 0.63 eV and an increase in the photogenerated current by over 60% compared with pure amorphous TiO 2 . Furthermore, the nanocomposites demonstrate excellent stability during the 1 h continuous photocurrent generation test.