Toward Expanding the Optical Response of Ag₂CrO₄ and Bi₂O₃ by Their Laser-Mediated Heterojunction

Abstract

The formation of heterojunctions between semiconductors with distinct properties usually expands their capabilities. In this context, many methodologies have been employed in pursuing efficient and fruitful heterojunctions. However, poor attention has been paid to the employment of photonics-based strategies, which lately demonstrated to have great potential for the structural modification of semiconductors. In the current work, we report the laser-mediated generation of heterojunctions between Ag2CrO4 and Bi2O3, two semiconductors with contrasting properties. The products were prepared by the laser irradiation of different semiconductor’s mixture ratios and further analyzed using various electron- and photon-based characterization techniques, different from mechanical grinding, which is considered the most straightforward way to obtain heterojunctions. The laser’s intense optical field prompted not only the formation of tight and uniform junctions between the composing semiconductors but also induced Ag and Bi nanoparticles’ production on their surfaces. This resulted in a modulation of the optical band gap to the narrowest value found in the semiconductor components and low recombination of the photoinduced charge carriers regardless of the amount ratio of the composing semiconductors. Therefore, this work will be of great importance for the creation of materials with a potential exploitability in the light-powered sectors.

Formation of Metallic Ag on AgBr by Femtosecond Laser Irradiation

“…Additionally, we addressed the formation of In nanoparticles on the surface of irradiated indium phosphide (InP) [24], the formation of AgBi nanoalloys by FLI [25], and a theoretical report on the miscibility of Ag and Bi atoms to form AgBi nanoalloys [26]. Very recently, we obtained the formation of a heterojunction between Ag 2 CrO 4 and Bi 2 O 3 by FLI [27]. These studies allowed us to disclose the breaking/forming processes of the corresponding chemical bonds associated with the changes in the structure and properties of the irradiated materials.…”