Proceedings of International Conference on Perovskite and Organic Photovoltaics and Optoelectronics (IPEROP19)
DOI: https://doi.org/10.29363/nanoge.iperop.2019.070
Publication date: 23rd October 2018
Semi-transparent perovskite solar cells (ST-PSCs) are highly attractive to improve the efficiency of commercial silicon (Si) and CIGS (copper indium gallium selenide) photovoltaic modules in tandem architectures. However, the commercial deployment of ST-PSCs is limited by stability and the development requires high IR transparency requirements.
In this work, efficient rigid and flexible semi-transparent perovskite solar cells (ST-PSCs) were prepared in inverted (light incidence through hole transport layer) configuration. All layers were deposited by a combination of low-temperature solution-based, sputtering and spatial atomic layer deposition (sALD) techniques, which can be potentially up-scalable for sheet to sheet and roll to roll manufacturing lines. The rigid and flexible opaque PSCs reach stabilized power conversion efficiency (PCE) of 19% and 16% [1], while rigid ST-PSC reaches 16.4% stabilized PCE. Besides those results, we have developed our current flexible opaque stack to the flexible semi-transparent stack using top TCO electrode and sALD buffer layer. We also highlight that the inverted configuration exhibited extremely high infrared transparency [2] and a remarkable stability during the light and thermal stress. The encapsulated ST-PSCs retained 93% of their initial stabilized PCE after 3000h aging at 85°C in a nitrogen atmosphere. Interestingly, using highly transparent transport layers, rigid and flexible ST-PSCs show comparable efficiency by illumination from both rear and front TCO sides, resulting in a bifacility of 99%.
In order to use the ST-PSCs in 4-terminal tandem architecture in combination with bottom c-Si and CIGS cells, the high near-infrared transmission (average 93%) of the ST-PSCs was optimized by improving TCO quality and tuning the thickness of component layers in cells [2]. The ST-PSC with optimized IR transparency was coupled with 6-inch ECN part of TNO (silicon heterojunction) SHJ c-Si bottom cell leading to 26.3% efficiency (with a possibility to further improvement by increasing the transparency of TCO electrodes and tuning the perovskite bandgap). Furthermore, using flexible ST-PSCs in combination with flexible CIGS cells, we created efficient flexible 4T tandem devices. The 4T tandem cells efficiencies are determined with the tandem measurement procedure as described by Werner et al. [3].
In conclusion, the stability, efficiency, IR transparency and scalability of PSCs developed for hybrid tandem applications, is reported. Further improvement on transparency and efficiency of our ST-PSCs and consequently on the enhancement of our tandem results will be reported during the conference. By combining the rigid and flexible ST-PSCs with c-Si and CIGS bottom cells state-of-the-art results are obtained.
The work was financially supported by Rijksdienst voor Ondernemend Netherland (TKI project HIPER TEUE116PYUOU and PPS-toeslag TKI-Energie POP-ART project No. 1621103). The work also has been supported by Solliance, a partnership of R&D organizations from the Netherlands, Belgium, and Germany working in thin film photovoltaic solar energy.