Search

While perovskite photovoltaic (PV) devices are on the verge of their commercialization, promising methods to recycle or remanufacture fully-encapsulated perovskite solar cells (PSCs) and modules are still missing. Through detailed life-cycle assessment shown in this work, we identify that the majority of the greenhouse gas emissions can be reduced by re-using the glass substrate and parts of the PV cells. Based on these analytical findings, we develop a novel thermally-assisted mechanochemical approach to remove the encapsulants, the electrode and the perovskite absorber, allowing to re-use most of the device constituents for remanufacturing PSCs, which recovered nearly 90% of their initial performance. This remanufacturing strategy allows to save up to 33% of the module’s global warming potential. Finally, we demonstrate that the CO2-footprint of these remanufactured devices can become less than 30g/kWh, which is the value for state-of-the-art c-Si PV modules and can even reach 15g/kWh assuming a similar lifetime

The photocurrent density-voltage (J(V)) curve is the fundamental characteristic to assess opto-electronic devices, in particular solar cells. However, it only yields information on the performance integrated over the entire active device area. Here, a method to determine a spatially resolved photocurrent image by voltage-dependent photoluminescence microscopy is derived from basic principles. The opportunities and limitations of the approach are studied by the investigation of III-V and perovskite solar cells. This approach allows the real-time assessment of the microscopically resolved local J(V) curve, the steady-state Jsc, as well as transient effects. In addition, the measurement contains information on local charge extraction and interfacial recombination. This facilitates the identification of regions of non-ideal charge extraction in the solar cells and enables to link these to the processing conditions. The proposed technique highlights that, combined with potentiostatic measurements, luminescence microscopy turns out to be a powerful tool for the assessment of performance losses and the improvement of solar cells.

The perovskite based solar cells is a new generation solar cell type, the perovskite crystals act as photo-charge-generating materials with organic and inorganic elements more commonly referred to as "halide hybrid perovskite" (ABX3 with A the organic part, B the inorganic part and X an halogen). In addition, they are low-cost materials that are easy to develop, which is a major advantage for this type of cell. There are different types of perovskite-based solar cells (PSC) with different designs. This work focuses on the so-called "monolithic" PSC configuration, which is composed of different porous layers; including TiO2 deposited from commercial pastes by "screen-printing" technique into perovskite crystals infiltrate. In this cell graphite (p type) is used as cathode while FTO (Fluorine Tin Oxide, n type) on glass is used as anode. The aim is to obtain a TiO2 layer with a higher porous volume with respect to the one done commercially, so the quantity of photo-active materials that infiltrates it can be increased and in this sense higher efficiency could be reached. Indeed, up to 9% has been obtained for the optimized cells with the new configuration of porous TiO2 layer obtained by bead molding in comparison with a 6% for reference cells (commercially produced porous layer)., Les cellules solaires à base de pérovskite sont considérées comme cellules de nouvelles génération, les cristaux de pérovskite jouent le rôle de matériaux photo-générateurs de charges avec des éléments organiques et inorganiques plus communément appelés « perovskite hybride halogéné » (ABX3 avec avec A la partie organique, B la partie inorganique et X un halogène). De plus, ce sont des matériaux à faible coût et simple à élaborer ce qui présente un avantage majeur pour ce genre de cellule. Il existe différents types de cellules à base perovskite (PSC) avec différentes architectures. Ce travail porte plus particulièrement sur la configuration de PSC dite « monolithique » qui est composée de différentes couches poreuses, dont le TiO2 déposé à partir de pâtes commerciales par « screen-printing » dans lesquelles s’infiltrent les cristaux de perovskite. Dans cette cellule le graphite (type p) est utilisé comme cathode tandis que le FTO (Fluorine Tin Oxide, type n) sur verre est utilisé comme anode. Le but est d’obtenir une couche TiO2 avec un volume poreux plus important par rapport à celui réalisé par voie commerciale, afin d’augmenter la quantité de matériaux photo-actifs qui s’y infiltre et d’atteindre ainsi un rendement supérieur. En effet, jusqu’à 9% a été obtenu pour les cellules optimisées avec la nouvelle configuration de couche poreuse de TiO2 obtenue par moulage de billes contre 6% pour les cellules références (couche poreuse élaboré par voie commerciale).