Combined DFT and MD simulation approach for the investigation of intrinsic material properties of T-phase Rb2Se monolayer

Two-dimensional monolayers are a prime class of materials due to their extensive spectrum of applications. In the present study, the material characteristics of the 1T-Rb2Se monolayer are investigated and analysed by employing the first-principles DFT calculations. The computations of structural, electronic, bonding nature, dynamical, optical, thermoelectric, and elastic properties of the theoretically predicted 1T-Rb2Se monolayer are effectuated. The 1T-Rb2Se monolayer displays a semiconducting nature with the energy gap quantified using various exchange-correlational potentials. The phonon and CPMD was deployed for the conclusions on the dynamical and thermal stabilities. With indirect band gap and good thermal response, the material will have possible applications in photovoltaics and thermoelectrics. Positive Poisson's ratio and elastic tensors validates the elastic strength of the monolayer. The effective masses of charge carriers and its relative ratio are determined from the energy band paraboloids with the deformation potentials for the accuracy of the relaxation time. The 1T-Rb2Se is electronically, ionically, dynamically, thermally, and elastically stable that confirms its feasibility for experimental studies. •Rb2Se monolayer possess a trigonal honey-comb structure.•Molecular Dynamics (MD) was used to study the thermal stability of the monolayer.•The 2D network of Rb2Se monolayer is a semiconductor with an indirect band gap of about 1.59 eV.•The monolayer exhibits good absorption and medium reflectivity in the visible range of the electromagnetic spectrum that makes the monolayer a promising material in photovoltaics and nano-optoelectronics.•The results from the Figure of merit provide material applications in thermo-electric devices.