Electromagnetic resonances of solar-selective absorbers with nanoparticle arrays embedded in a dielectric layer

•A solar-selective absorber with tungsten core-shell nanoparticle arrays embedded in an SiO2 layer was proposed.•3D full-wave simulations were performed to investigate the geometric effects.•Broadband light absorption in the visible to near-infrared wavelength range was achieved.•Underlying mechanisms for the enhanced selective absorption of solar light was elucidated.

We numerically investigate a solar-selective absorber with tungsten core-shell nanoparticle arrays embedded in an SiO2 layer. The 3D full-wave finite-difference time-domain (FDTD) simulations are performed to investigate the geometric effects of different types of solar-selective absorbers. Consequently, broadband light absorption was achieved with either a tungsten nanoparticle array or a tungsten core-shell nanoparticle array because of the strong electric field enhancement in the gap between the core nanoparticles. The solar performance of the proposed structure is shown for high-efficiency solar light absorption. This study enhances understanding of the light absorption mechanism of metallic nanoparticle/dielectric composite and facilitates the design of high-efficiency solar-selective absorbers.