Sammanfattning
The power conversion efficiency (PCE) of perovskite and organic solar cells have improved rapidly in recent years and lab-scale devices are now inching ever closer to the Shockley-Queisser (S-Q) limit. Now, the biggest challenge on the path to commercialization is to improve stability and enable scalable manufacturing of these devices, without loss of PCE. In this work, I suggested ways to adapt current device designs to maintain current performance, while striving towards stable, scalable thin-film solar cells.
I described the electrical potential landscape, i.e. the distribution of potential across various layers, in organic and perovskite solar cells, and how it relates to voltage losses in the devices. The results herein are based on extensive drift-diffusion simulations, cross-referenced with experimental data. I performed simulations for a wide range of parameters and analysed current state-of-the-art devices from a device-physical perspective, to learn how devices properties and designs affect performance.
The primary result of this work is a theoretical description of how the properties of the device and its layers can be related to maximum
power point voltage and more generally, to various parts of jU-curves. I showed how various loss mechanisms, such as recombination at material interfaces and poor charge extraction, can be quantified in terms of voltage loss, and thereby directly related to the PCE of the device.
Based on the results, I discussed strategies for designing stable, scalable devices approaching the S-Q limit. I found that, the most straightforward way is to design devices with a large built-in voltage, which played a key role in all devices studied in this work. The built-in voltage helps mitigate additional losses resulting from thicker layers in large-scale manufacturing and less effective, but more stable dopants. Thus, this work can help researchers both understand the performance of current devices and guide future device design.
I described the electrical potential landscape, i.e. the distribution of potential across various layers, in organic and perovskite solar cells, and how it relates to voltage losses in the devices. The results herein are based on extensive drift-diffusion simulations, cross-referenced with experimental data. I performed simulations for a wide range of parameters and analysed current state-of-the-art devices from a device-physical perspective, to learn how devices properties and designs affect performance.
The primary result of this work is a theoretical description of how the properties of the device and its layers can be related to maximum
power point voltage and more generally, to various parts of jU-curves. I showed how various loss mechanisms, such as recombination at material interfaces and poor charge extraction, can be quantified in terms of voltage loss, and thereby directly related to the PCE of the device.
Based on the results, I discussed strategies for designing stable, scalable devices approaching the S-Q limit. I found that, the most straightforward way is to design devices with a large built-in voltage, which played a key role in all devices studied in this work. The built-in voltage helps mitigate additional losses resulting from thicker layers in large-scale manufacturing and less effective, but more stable dopants. Thus, this work can help researchers both understand the performance of current devices and guide future device design.
| Originalspråk | Engelska |
|---|---|
| Handledare |
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| Förlag | |
| Tryckta ISBN | 978-952-12-4406-3 |
| Elektroniska ISBN | 978-952-12-4407-0 |
| Status | Publicerad - 2024 |
| MoE-publikationstyp | G5 Doktorsavhandling (artikel) |