Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV22)
DOI: https://doi.org/10.29363/nanoge.hopv.2022.064
Publication date: 20th April 2022
In ten years, halide perovskite (PVSK) solar cells reached efficiency comparable to silicon photovoltaic (PV) on small area devices [1]. This promising new PV technology can further be considered for industrial exploitation if the performance gap between laboratory cells and module devices will be nullify. The main scaling up issues are related to module design, interconnection patterning and material/process optimization [2]. In literature, few works showed high efficiency n-i-p module, but without reporting both reverse and forward scan, and statistics of the fabricated devices [3–6]. The hysteresis analysis, if present, revealed a huge discrepancy between the efficiency in reverse and forward (HI˃1.1). This anomalous hysteretic behavior of PVSK-based devices is still one of the obstacles in the pathway of their commercialization [7]. Moreover, during the fabrication process, many defects trap states and grain boundaries can occur [8]. Since the surface is where defects are mainly localized in any kind of solar cell, the PVSK surface passivation is one of the most efficient methods to suppress nonradiative recombination losses, and to improve charge carrier extraction and photovoltage [9,10].
In our work, by performing a judicious design of the module and cells interconnections with the transfer length method (TLM), exploiting interfacial defects PEAI (phenethylammonium iodide) passivation at module level (first time in literature) and optimizing an iodine rich triple cation composition and the related deposition procedure to avoid the detrimental effect of DMSO (dimethyl sulfoxide) solvent trapping during film formation, we report highly efficient n-i-p modules (10 cm2 active area with 91% aspect ratio, reproducibility with 2% error) able to achieve an efficiency of 19.1% (reverse scan) – 18.5% (forward scan) with negligible hysteresis index (HI=1.03). Moreover, the scaling up losses have been reduced to only 8% (small area cell efficiency was 20.6%) showing the good passivation of defects, the optimal layers homogeneity on small and large area devices and the optimized patterning process by laser technique. We demonstrated the quality and the defects-free layers by materials (SEM, XRD, microscope images, PL, thickness, roughness, UV-vis) and device characterization (JV curves, MPPT, IPCE, LBIC).
The authors were supported by the European Union’s Horizon 2020 Framework Program for funding Research and Innovation under grant agreements no. 764047 (ESPResSo) and no. 826013 (IMPRESSIVE). The authors acknowledge the project UNIQUE, supported under the umbrella of SOLAR-ERA.NET_cofund by ANR, PtJ, MUR (GA 775970), MINECOAEI, SWEA, within the European Union Framework Programme for Research and Innovation Horizon 2020 (Cofund ERANET Action, No. 691664).