Novel functional 2D-materials based on nanoporous alumina lattices

• Applicant: Dr. Mikhail Pashchanka
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 348124222

Within the scope of this project, we propose to modify several important compositional, morphological, and optical properties of porous anodic aluminium oxide (PAOX) films for the first time, and explore their potential use in diverse emerging fields of nanotechnology, as well as in the fabrication of novel 2D inverse photonic systems that can be theoretically predicted, but have never been reported till date.It is widely known that the conventional fabrication of PAOX layers results in a high content of entrapped acid electrolyte impurities. This anionic contamination impedes many practical applications and leads to changeable thermal, mechanical, and especially optical properties of 2D-photonic alumina crystals. We intend to develop a novel non-destructive, low-temperature method for minimizing the content of undesired reactive electrolyte species, achieving reproducible optical constants (refractive indices), and retention of other versatile properties of 2D amorphous porous films, such as the mechanical stability, optical transparency, and solubility in a moderately concentrated acidic and alkaline medium.Furthermore, we plan to achieve a homogeneous in situ doping of the PAOX matrix with chromium or titanium ions, followed by the conversion into ruby or sapphire 2D photonic lattices for lasing applications. Although ruby and sapphire are conventional solid-state laser materials, their application in the manufacturing of inverse 2D photonic laser architectures still remains unexplored.In addition, we propose controllable randomization of the nanopore layout to achieve bio-inspired, black antireflective PAOX surfaces for light entrapping (similar to black silicon, based on so-called "moth eye effect"). Although PAOX is not intrinsically black, the absorption of light can be theoretically achieved within the transparent dielectric medium due to the photonic effects and destructive optical interference.

• DFG Programme: Research Grants
• International Connection: USA
• Co-Investigator: Professor Dr. Jörg J. Schneider
• Cooperation Partners: Dr. Karsten Bittkau; Professor Dr. Mikhail Noginov