Abstract
Improving the efficiency of solar cells through novel materials and devices is critical to realize the full potential of solar energy to meet the growing worldwide energy demands. We present here a highly efficient radial p-n junction silicon solar cell using an asymmetric nanowire structure with a shorter bottom core diameter than at the top. A maximum short circuit current density of 27.5 mA/cm2 and an efficiency of 7.53% were realized without anti-reflection coating. Changing the silicon nanowire (SiNW) structure from conventional symmetric to asymmetric nature improves the efficiency due to increased short circuit current density. From numerical simulation and measurement of the optical characteristics, the total reflection on the sidewalls is seen to increase the light trapping path and charge carrier generation in the radial junction of the asymmetric SiNW, yielding high external quantum efficiency and short circuit current density. The proposed asymmetric structure has great potential to effectively improve the efficiency of the SiNW solar cells.
Highlights
(DB) at the bottom than at the top (DT), similar to a funnel or an inverted nanoconical silicon nanowire (SiNW), while a symmetric SiNW has DT same as diameter at the bottom (DB). (b) Tilted view (45°) SEM image of the SiNW arrays. (c) Enlarged view of the asymmetric SiNW with DT of 370 nm and DB of 290 nm before p-type shell deposition
The fabricated device consists of an array of radial p-n junction asymmetric SiNWs, back surface field (BSF) layer, Al back reflector and Ag top electrode
The asymmetric SiNW was designed with its core diameter at the bottom (DB) shorter than at the top (DT), while conventional vertical symmetric SiNW has DT identical to DB
Summary
(DB) at the bottom than at the top (DT), similar to a funnel or an inverted nanoconical SiNW, while a symmetric SiNW has DT same as DB. (b) Tilted view (45°) SEM image of the SiNW arrays. (c) Enlarged view of the asymmetric SiNW with DT of 370 nm and DB of 290 nm before p-type shell deposition. The fabrication process of the asymmetric SiNW solar cell consisted of four steps (Supplementary Fig. S1).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
