Conjugated polymer-silicon nanowire array hybrid Schottky diode for solar cell application

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Silicon nanowire arrays (SiNWs) offer promising properties for photovoltaic applications.
• Hybrid organic-inorganic Schottky diodes are explored for enhanced solar cell performance.
• Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) is a conductive polymer used in organic electronics.

Purpose of the Study:

• To fabricate and optimize hybrid Schottky diodes using SiNWs and PEDOT:PSS for high-efficiency solar cells.
• To investigate the impact of SiNW morphology (length and density) on device performance.
• To understand the charge recombination mechanisms limiting solar cell efficiency.

Main Methods:

• Fabrication of SiNW arrays on silicon substrates via metal-assisted chemical etching.
• Tuning SiNW length by adjusting etching time and controlling inter-wire distance using PCl(5) immersion.
• Device fabrication by spin-casting PEDOT:PSS onto SiNW arrays.
• Characterization using current-voltage (I-V) measurements and transient photovoltage decay analysis.

Main Results:

• SiNW length and density were successfully controlled.
• Optimized SiNW morphology led to a power conversion efficiency of 7.3%, significantly outperforming planar devices.
• Analysis indicated that charge recombination is a primary factor affecting device performance.

Conclusions:

• The morphology of SiNW arrays critically influences the electrical output characteristics of hybrid solar cells.
• Optimized SiNW-PEDOT:PSS hybrid Schottky diodes demonstrate significantly improved power conversion efficiency.
• Mitigating charge recombination is essential for further enhancing the performance of these solar cells.