6 research outputs found
An Interlaboratory Study on the Stability of All-Printable Hole Transport Material–Free Perovskite Solar Cells
Comparisons between different laboratories on long-term stability analyses of perovskite solar cells (PSCs) is still lacking in the literature. This work presents the results of an interlaboratory study conducted between five laboratories from four countries. Carbon-based PSCs are prepared by screen printing, encapsulated, and sent to different laboratories across Europe to assess their stability by the application of three ISOS aging protocols: (a) in the dark (ISOS-D), (b) under simulated sunlight (ISOS-L), and (c) outdoors (ISOS-O). Over 1000 h stability is reported for devices in the dark, both at room temperature and at 65 degrees C. Under continuous illumination at open circuit, cells survive only for few hours, although they recover after being stored in the dark. Better stability is observed for cells biased at maximum power point under illumination. Finally, devices operate in outdoors for 30 days, with minor degradation, in two different locations (Barcelona, Spain and Paola, Malta). The findings demonstrate that open-circuit conditions are too severe for stability assessment and that the diurnal variation of the photovoltaic parameters reveals performance to be strongly limited by the fill factor, in the central hours of the day, due to the high series resistance of the carbon electrode
Studying the outdoor performance of organic building-integrated photovoltaics laminated to the cladding of a building prototype
The outdoor dependence of module orientation and diurnal climatic conditions on the performance of Organic Photovoltaics (OPVs) configured for Building Integrated PV (BIPV) arrays is reported. The study focuses upon a Northern European climate and the significance of module orientation upon energy yield across diurnal, seasonal change and climatic conditions are discussed. It is shown that the optimum position of a BIPV facade depends upon season and that a south facing BIPV facade provides the greatest energy yield during winter months. The results also show how west-facing modules can significantly contribute to power generation during peak power periods (5–8 p.m.), which is imperative for balancing energy demand for buildings of the future and in particular supply the energy needs of buildings during peak hours in Northern Europe. Electrical characteristics under standard and part-load conditions were collated from laboratory scale OPV module experimental data and scaled for commercial-size modules in order to simulate BIPV arrays based upon OPVs. The simulated data is compared to experimental data and the closeness shows that BIPV systems based upon OPVs can be accurately simulated prior to installation. The system simulations compare typical energy demand profiles of small commercial buildings and illustrate that OPV arrays show strong potential to be used with excess energy generation for 8 months of the year based upon a 4.22kWp OPV system. Four 4.22kWp OPV systems scenarios have been investigated for (1) the highest annual energy generation, (2) architecturally evenly-spaced around the building (avoiding a North façade), (3) grid-balancing and (4) East-West split. Whilst Scenario 4 shows the lowest overall energy yield over the course of the year, energy production during peak hours is substantially higher than in other scenarios. The options presented show that OPVs are viable to use in BIPVs and can adequately meet the energy demand of a small commercial building during spring, summer and autumn in Norther Europe and can be adapted to end user's needs
Rapid evaluation of different perovskite absorber layers through the application of depth profile analysis using glow discharge – Time of flight mass spectrometry
Depth profile analysis of perovskite absorber layers deposited onto glass substrates is investigated by radiofrequency pulsed glow discharge - time of flight mass spectrometry (rf-PGD-ToFMS). Elemental depth profiles obtained for perovskite films fabricated using a double-step deposition route with different precursors (methylammonium iodide and PbI2, PbCl2 or PbBr2) show varying distribution of the principle components depending on the precursors employed. Furthermore, the results show that rf-PGD-ToFMS allows to identify traces of residue solvent used in the initial film preparation (dimethyl sulphoxide or dimethylformamide) and to identify differences produced by film thickness and oxygen uptake caused by exposure to ambient conditions. The approach also enables inspection of the differences in elemental diffusion and the degradation processes. By using rf-PGD-ToFMS, no ultra-high-vacuum is needed for processing and rapid analysis of absorber films can be obtained in less than 40 s. The demonstration of such powerful analytical technique for obtaining depth profile information could enable groups in the field to better optimize processing conditions and enhance stability
Spray coated silver nanowires as transparent electrodes in OPVs for Building Integrated Photovoltaics applications
Correction: High performing AgNW transparent conducting electrodes with a sheet resistance of 2.5 Ω Sq−1 based upon a roll-to-roll compatible post-processing technique
From Crossref via Jisc Publications RouterArticle version: VoRCorrection for ‘High performing AgNW transparent conducting electrodes with a sheet resistance of 2.5 Ω Sq−1 based upon a roll-to-roll compatible post-processing technique’ by D. Kumar et al., Nanoscale, 2019, DOI: 10.1039/c8nr07974a