Substantial Improvement of Short Wavelength Response in n-SiNW/PEDOT:PSS Solar Cell

We report herein on the effects of silicon nanowire with different morphology on the device performance of n-SiNW/PEDOT:PSS hybrid solar cells. The power conversion efficiency (PCE) and external quantum efficiency (EQE) of the SiNW/PEDOT:PSS hybrid solar cells can be optimized by varying the length of the silicon nanowires. The optimal length of silicon nanowires is 0.23 mu m, and the hybrid solar cell with the optimal length has the V-oc of 569 mV, J(sc) of 30.1 mA/cm(2), and PCE of 9.3 %. We fabricated more isolated silicon nanowires with the diluted etching solution. And the J(sc) of the hybrid solar cell with more isolated nanowires has a significant enhancement, from 30.1 to 33.2 mA/cm(2). The remarkable EQE in the wavelength region of 300 and 600 nm was also obtained, which are in excess of 80 %. Our work provides a simple method to substantially improve the EQE of hybrid solar cell in the short wavelength region.