Ultra-broadband and wide-angle solar absorber for the All-MXene grating metamaterial

Excellent broadband absorption features have broad applications such as photoelectric conversion, optical communication, and photovoltaic cells. In the work, the absorption for a simple and easily fabricated all-MXene grating metamaterial absorber is investigated by using finite-difference time-domain (FDTD) method. The results show that the maximum absorption of the all-MXene grating absorber is higher than 98.5%, and the average absorption up to 90% in the range of 400 nm–2500 nm. The mechanism of broadband absorption is analyzed through using the electric field, magnetic field, and impedance theories. Furthermore, the absorption spectra of the all-MXene grating metamaterial absorber in different polarization states and incidence angles are investigated, and the results show that the wide-angle absorption from 0 to 70° can be realized by the proposed all-MXene grating metamaterial absorber, and the absorption was also independent on the polarization of the light. Lastly, we can apply the advantages of the all-MXene grating metamaterial to solar metamaterial absorbers, which have almost the same absorption spectra as the AM1.5 solar spectra, indicating the all-MXene grating metamaterial absorber have high absorption efficiency and low energy loss. These findings suggest potential applications of the all-MXene grating metamaterial absorber in many fields, including solar batteries, photovoltaics, and solar thermal conversion.