Carbon-based monochalcogenides for efficient solar and heat energy harvesting

[Display omitted] •DFT investigation of carbon-based monochalcogenides with various structural morphology.•A broad range of electronic band gap (0.55 to 1.52 eV) with a direct–indirect transition.•Hinge-like structure of puckered geometry reveals anisotropic phonons and carrier mobility.•Excellent carrier mobility (174.698m2V-1s-1) and thermoelectric power factor of puckered CS material.•Achieved 19.61 % solar power conversion efficiency for puckered CTe material. A new generation of two-dimensional (2D) material has captivated significant attention in the energy conversion field owing to their promising optoelectronics and thermoelectric applications. The present work involves the systematic investigation of fundamental properties of single-layered 2D carbon-based monochalcogenides (CS, CSe, CTe) with planar, buckled and puckered geometry within the framework of density functional theory (DFT). The structural and lattice dynamics analysis disclose that puckered and buckled configurations are energetically and dynamically stable whereas planar structures depict instability. The anisotropic group velocity of longitudinal acoustic (LA) and transverse acoustic (TA) phonon modes in puckered systems may render the characteristics thermal transport properties. Additionally, for the first time, we scrutinized the thermoelectric and optical properties of these materials. At room temperature, the electron carrier mobilities are 174.698 and 160.830m2V-1s-1 of puckered and buckled CS systems, respectively are highest among all structures. The computed Seebeck coefficient, electrical conductivity and power factor manifests the high thermoelectric transport properties of puckered CS material. Further, the calculated solar parameters demonstrate an exceptionally high-power conversion efficiency of 19.61 % for puckered CTe. Present work indicates that puckered phase of CS and CTe show their potential for the heat and solar energy harvesting devices, respectively.