Publications by authors named "Eloi Ros"
Interface Engineering in All-Oxide Photovoltaic Devices Based on Photoferroelectric BiFeCoO Thin Films.
ACS Appl Electron Mater
November 2024
Article Synopsis
- Photoferroelectric BiFeO (BFO) is a lead-free material being studied for use in thin film photovoltaic devices, but its efficiency remains low despite ongoing improvements in device architecture.
- This research investigates how adding a ZnO layer to a BiFeCoO (BFCO) heterostructure affects its ferroelectric and photoresponse properties, revealing a significant increase in short circuit current when compared to devices without ZnO.
- Findings indicate that the enhanced performance is due to better band energy alignment at the ZnO/BFCO interface, which minimizes charge recombination, highlighting ZnO's potential in improving the functionality of BFO-based optoelectronic devices.
Poly(amidoamine) (PAMAM) dendrimers are used to modify the interface of metal-semiconductor junctions. The large number of protonated amines contributes to the formation of a dipole layer, which finally serves to form electron-selective contacts in silicon heterojunction solar cells. By modification of the work function of the contacts, the addition of the PAMAM dendrimer interlayer quenches Fermi level pinning, thus creating an ohmic contact between the metal and the semiconductor.
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- High open-circuit voltage in SbSe solar cells poses challenges for creating eco-friendly solar technology, as current methods use CdS layers that raise environmental concerns due to cadmium toxicity.
- This research introduces a ZnO-based buffer layer with a polymer film on top to replace the toxic CdS, which significantly boosts solar cell performance, achieving an open-circuit voltage increase from 243 mV to 344 mV.
- The study highlights the effectiveness of using branched polyethylenimine at the ZnO interface, yielding a maximum solar cell efficiency of 2.4% and laying the groundwork for further advancements in the field of chalcogenide photovoltaics.
In this work, a new design of transparent conductive electrode based on a graphene monolayer is evaluated. This hybrid electrode is incorporated into non-standard, high-efficiency crystalline silicon solar cells, where the conventional emitter is replaced by a MoO selective contact. The device characterization reveals a clear electrical improvement when the graphene monolayer is placed as part of the electrode.
View Article and Find Full Text PDFAs optoelectronic devices continue to improve, control over film thickness has become crucial, especially in applications that require ultra-thin films. A variety of undesired effects may arise depending on the specific growth mechanism of each material, for instance a percolation threshold thickness is present in Volmer-Webber growth of materials such as silver. In this paper, we explore the introduction of aluminum in silver films as a mechanism to grow ultrathin metallic films of high transparency and low sheet resistance, suitable for many optoelectronic applications.
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