Photoelectric Properties of Silicon Nanocrystals/P3HT Bulk-Heterojunction Ordered in Titanium Dioxide Nanotube Arrays

A silicon nanocrystals (Si-ncs) conjugated-polymer-based bulk-heterojunction represents a promising approach for low-cost hybrid solar cells. In this contribution, the bulk-heterojunction is based on Si-ncs prepared by electrochemical etching and poly(3-hexylthiophene) (P3HT) polymer. Photoelectric properties in parallel and vertical device-like configuration were investigated. Electronic interaction between the polymer and surfactant-free Si-ncs is achieved. Temperature-dependent photoluminescence and transport properties were studied and the ratio between the photo- and dark-conductivity of 1.7 was achieved at ambient conditions. Furthermore the porous titanium dioxide (TiO2) nanotubes’ template was used for vertical order of photosensitive Si-ncs/P3HT-based blend. The anodization of titanium foil in ethylene glycol-based electrolyte containing fluoride ions and subsequent thermal annealing were used to prepare anatase TiO2nanotube arrays. The arrays with nanotube inner diameter of 90 and 50 nm were used for vertical ordering of the Si-ncs/P3HT bulk-heterojunction

Low-Temperature Atmospheric Pressure Plasma Processes for “Green” Third Generation Photovoltaics

Special Issue: Plasma Processing of Materials for Energy Conversion and Storage.International audienceAtmospheric pressure plasmas (APPs) have achieved great scientific and technological advances for a wide range of applications. The synthesis and treatment of materials by APPs have always attracted great attention due to potential economic benefits if compared to low-pressure plasma processes. Nonetheless, APPs present very distinctive features that suggest atmospheric pressure operation could bring other benefits for emerging new technologies. In particular, materials synthesized by APPs which are suitable candidates for third generation photovoltaics are reviewed here

Dramatic Enhancement of Photoluminescence Quantum Yields for Surface-Engineered Si Nanocrystals within the Solar Spectrum

Substantial improvements of the absolute photoluminescence quantum yield (QY) for surfactant-free silicon nanocrystals (Si-ncs) by atmospheric pressure microplasma 3-dimensional surface engineering are reported. The effect of surface characteristics on carrier multiplication mechanisms is explored using transient induced absorption and photoluminescence QY. Surface engineering of Si-ncs is demonstrated to lead to more than 120 times increase in the absolute QY (from 0.1% up to 12%) within an important spectral range of the solar emission (2.3-3 eV). The Si-ncs QY is shown to be stable when Si-ncs are stored in ethanol at ambient conditions for three months