High Performance Organic-Nanostructured Silicon Hybrid Solar Cell with Modified Surface Structure

Xiaoli Duan,Xiaofeng Zhang,Yunfang Zhang

doi:10.1186/s11671-018-2703-2

Abstract

Silicon nanowires (SiNWs) with excellent light trapping properties have been widely applied in photovoltaic devices, which provide opportunities for boosting the photons harvested by Si. However, the photoexcited carriers are easily trapped and recombined by high-density surface defects due to higher surface area prolonging to depth of nanowire. In this work, in order to reduce the surface defects and recombination rate of SiNWs, a simple solution process is used to modify the surface structure. Applying the tetramethyl ammonium hydroxide (TMAH) treatment leads to smooth and taper Si NW surface, which improves the open-circuit voltage (Voc) and fill factor (FF) obviously. Thus, a champion PCE of 14.08% is achieved for the nanostructured Si/PEDOT:PSS hybrid device by 60-s TMAH treatment. It also indicates that TMAH treatment promises a simple and effective method for enhancing Si NW-based devices.

Highlights

For the photovoltaic devices, the energy conversion efficiency is directly associated with the photos absorption property, which means the more photo incidences, the larger amount electrons can be generated
Despite of the strong optical enhancement, one problem is high surface recombination, which occurs with the high density of surface defects that are associated with the nanostructure
We explore the tetramethyl ammonium hydroxide (TMAH) treatment to modify the surface of Si Silicon nanowires (NWs), which is fabricated by

Summary

Introduction

The energy conversion efficiency is directly associated with the photos absorption property, which means the more photo incidences, the larger amount electrons can be generated. The light trapping properties of photovoltaic have been investigated in many works [1–4] Silicon nanostructures such as silicon nanowire, nanocone, or pyramid arrays have been widely applied due to excellent antireflection properties, which provide opportunities for boosting the photos harvested by Si [5–9]. These nanostructures can be fabricated by a variety of methods, including metal-assisted etching, vapor-liquid-solid growth, reactive ion etching, and laser fabrication [10, 11]. The increased photo carrier recombination decreases the cell efficiency by reducing device fill factor (FF) and open-circuit voltage (Voc) [12, 13]. This represents the importance of modifying the

Methods

Results

Conclusion