Photovoltaic properties of PSi impregnated with eumelanin.

Guido Mula,Susanna Setzu,Alessandro Pezzella,Laura Manca

doi:10.1186/1556-276x-7-377

Abstract

A bulk heterojunction of porous silicon and eumelanin, where the columnar pores of porous silicon are filled with eumelanin, is proposed as a new organic-inorganic hybrid material for photovoltaic applications. The addition of eumelanin, whose absorption in the near infrared region is significantly higher than porous silicon, should greatly enhance the light absorption capabilities of the empty porous silicon matrix, which are very low in the low energy side of the visible spectral range (from about 600 nm downwards). The experimental results show that indeed the photocarrier collection efficiency at longer wavelengths in eumelanin-impregnated samples is clearly higher with respect to empty porous silicon matrices.

Highlights

The relevance of solar power in the renewable energy field is constantly increasing due to its ready availability and to the fact that the available amount exceeds by several orders of magnitude the needs of the human race
We investigate here a new hybrid material for photovoltaic applications composed by n-type porous silicon (PSi) and eumelanin, a natural pigment featuring relatively high electrical conductivity [16] and believed to rely mainly on proton-based conduction [16,17,18]
The crude oligomer-containing mixture was acetylated according to an established protocol [40] and examined by thin layer chromatography (TLC)

Summary

Introduction

The relevance of solar power in the renewable energy field is constantly increasing due to its ready availability and to the fact that the available amount exceeds by several orders of magnitude the needs of the human race. Among the adopted strategies for new materials, interface geometry often plays a major role in the collection of photogenerated carriers, and bulk heterojunctions [3,9,10,11,12] - intimately mixing the two junction materials while keeping them separate in a ‘fractal like’ highsurface interface - are a very promising design for solar cells. This concept was introduced in the mid 1990s for

Methods

Results

Conclusion