Two-dimensional (2D) materials with suitable electronic and optical properties offer various possibilities for photocatalytic applications. Although various 2D materials have hitherto been specified as adequate candidates, materials with high photocatalytic efficiency for water splitting are still minimal. In this study, we predict a 2D Janus $\mathrm{Ge}\mathrm{P}\mathrm{As}$ monolayer and examine its capability for photocatalytic water splitting by performing first-principles calculations. The $\mathrm{Ge}\mathrm{P}\mathrm{As}$ monolayer is shown to possess robust dynamic and thermal stability. The direct electronic band gap in the visible region and band-edge positions of the strain-free and strained monolayers are revealed to be convenient for redox reactions in wide pH ranges. The low recombination probability of charge carriers ensured by high and anisotropic carrier mobility enhances the material’s photocatalytic potential. Optical response calculations, including many-body interactions, indicate significant optical absorption capacity in the UV-visible range. Furthermore, low exciton binding energy facilitates dissociation into free electrons and holes, promoting photocatalytic reactions. Our study suggests that the $\mathrm{Ge}\mathrm{P}\mathrm{As}$ monolayer is an ideal and remarkably promising material to be utilized in visible-light-driven photocatalytic applications.

In this study, we designed a platform based on a laser-driven approach for fast, efficient, and controllable MOF synthesis. The laser irradiation method was performed for the first time to synthesize Zn-based MOFs in record production time (approximately one hour) compared to all known MOF production methods with comparable morphology. In addition to well-known structural properties, we revealed that the obtained ZnMOFs have a novel optical response, including photoluminescence behavior in the visible range with nanosecond relaxation time, which is also supported by first-principles calculations. Additionally, photocatalytic degradation of methylene blue with ZnMOF was achieved, degrading the 10 ppm methylene blue (MB) solution 83% during 1 min of irradiation time. The application of laser technology can inspire the development of a novel and competent platform for a fast MOF fabrication process and extend the possible applications of MOFs to miniaturized optoelectronic and photonic devices.

Recently, novel two-dimensional (2D) GeP and GeAs systems have been fabricated by mechanical exfoliation and utilized in various applications. These developments have brought the 2D germanium-pnictogens, C2/m-GeX (X = N, P, As, Sb, and Bi) structures into the limelight. In this study, we systematically investigate the structural, mechanical, electronic, and charge carrier transport properties of GeX monolayers by using first-principles methods. Our results show that the considered systems are dynamically stable and possess anisotropic physical properties. Examined structures are found to be flexible, and their mechanical strength and stiffness decrease down the group-V, in line with the trends of the bond strength, cohesive energy, charge transfer, and electron localization function. Additionally, the zigzag in-plane direction is mechanically superior to the armchair direction. The electronic band structure calculations based on HSE06 hybrid functional with the inclusion of spin–orbit coupling indicate that GeX monolayers are either direct or quasi-direct semiconductors with band gaps lying within the infrared and visible spectrum. The estimated charge carrier mobilities are highly anisotropic and also differ significantly depending on the structure and carrier type. These unique properties render GeX monolayers as suitable 2D materials for flexible nanoelectronic applications.

Two-dimensional (2D) Janus systems have garnered significant scientific interest owing to their novel properties and potential applications. The growing interest in these materials is driven by the idea that their structural asymmetry offers unprecedented opportunities for enhancing thermoelectric performance and unlocking groundbreaking advancements in energy conversion and waste heat utilization. In this context, we present a comprehensive study on the structural, vibrational, electronic, thermal, and thermoelectric properties of Janus ${\mathrm{Ge}}_2\mathrm{P}X(X=\mathrm{N},\mathrm{As},\mathrm{Sb},\mathrm{and}\mathrm{Bi})$ monolayers, using first-principles calculations combined with the Landauer formalism. The suggested configurations exhibit dynamical stability and retain structural integrity even at elevated temperatures. Electronic structure calculations employing hybrid functionals (HSE06) with spin-orbit coupling reveal that ${\mathrm{Ge}}_2\mathrm{PAs}$ and ${\mathrm{Ge}}_2\mathrm{PSb}$ monolayers exhibit anisotropic characteristics as indirect semiconductors, while ${\mathrm{Ge}}_2\mathrm{PN}$ and ${\mathrm{Ge}}_2\mathrm{PBi}$ exhibit metallic behavior. We also compare the thermal, electronic, and thermoelectric transport properties of these proposed monolayers to binary 2D GeP in the ballistic limit. Notably, both ${\mathrm{Ge}}_2\mathrm{PAs}$ and ${\mathrm{Ge}}_2\mathrm{PSb}$ exhibit $n$-type figure of merit ($ZT$) values exceeding 1 at 800 K, with their $n$-type $ZT$ values surpassing that of GeP at room temperature. Our analysis underscores the distinctive structural and electronic properties of ${\mathrm{Ge}}_2\mathrm{PAs}$ and ${\mathrm{Ge}}_2\mathrm{PSb}$ monolayers, accompanied by their highly promising thermoelectric performance. These findings position them as strong candidates for energy harvesting and conversion applications.