Broad-band Organic–Silicon Nanowire Hybrid Composites for Solar Energy Applications

In this work, a hybrid silicon/polymer super absorber is proposed combining nanowires made from amorphous silicon thin films and coated with a low-band-gap polymer. First, a comprehensive theoretical study of different silicon nanowires shapes and different polymer coatings is conducted using finite difference time-domain (FDTD) simulations to obtain the highest optical absorption (i.e., highest average absorption in the visible and near-infrared range). The optimized structure is then fabricated using a one-step technique for silicon nanowire formation and coated with the optimized polymer. The proposed fabrication technique results in the transformation of silicon from the amorphous to the crystalline state, enhancing its electrical properties. The proposed structure is composed of low-cost materials and fabricated using simple techniques and achieves excellent optical efficiency. This design also has the potential to play a major role in hybrid solar cells as it shows a theoretical maximum short-circuit current of 36.4 mA/cm2.