Tuning structural and optoelectronic properties of chalcogenophene-modified graphyne for photovoltaic applications

Bastos C.M.O.; da Silva Oliveira I.; de Oliveira Batista A.L.; Almeida Silva A.M.; Villegas C.E.P.; Dias A.C.; Marinho E.; Ribeiro Júnior L.A. · Journal of Materials Chemistry A (2026) · DOI: 10.1039/d6ta05506k

Resumen

Chalcogenophene-modified graphyne (chp-GY) monolayers constitute a versatile family of two-dimensional semiconductors with highly tunable physical properties. Using first-principles calculations based on Density Functional Theory (DFT) and the Bethe–Salpeter equation (BSE), we investigate the structural, mechanical, electronic, and optical properties of graphyne monolayers modified with furan (fu-GY), thiophene (thp-GY), selenophene (sep-GY), and tellurophene (tep-GY) pentagonal rings. All structures are found to be perfectly planar and exhibit excellent cohesive, mechanical, dynamical, and thermal stability at 300 K. The chp-GY systems display indirect semiconducting behavior, with band gaps ranging from 0.93 eV to 1.31 eV, suitable for visible and near-infrared light harvesting. Furthermore, varying the chalcogen atom enables effective tuning of the work function and electron affinity, which is advantageous for heterojunction photovoltaic applications. Optical calculations reveal strong absorption and pronounced excitonic effects, with exciton binding energies between 328 meV to 457 meV. Simulated single-junction solar cells exhibit favorable band alignment with common charge-transport layers such as TiO2 and P3HT, while the sep-GY monolayer achieves a theoretical maximum power conversion efficiency of 25.14 % in the radiative limit. These findings highlight chp-GY monolayers as promising candidates for next-generation optoelectronic and photovoltaic technologies. This journal is © The Royal Society of Chemistry, 2026.

Instituciones: Universidad Privada del Norte