Ma Tianshu, An Yidan, Li Sheng, Zhao Yue, Wang Huayang, Wang Changlei, Maier Stefan A, Li Xiaofeng
School of Optoelectronic Science and Engineering and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University, Suzhou 215006, China.
ACS Appl Mater Interfaces. 2022 Jul 6;14(26):29856-29866. doi: 10.1021/acsami.2c06393. Epub 2022 Jun 22.
Perovskite solar cells (PSCs) own rapidly increasing power conversion efficiencies (PCEs), but their concentrated counterparts (i.e., PCSCs) show a much lower performance. A deeper understanding of PCSCs relies on a thorough study of the intensive energy losses of the device along with increasing the illumination intensity. Taking the low band gap Sn-Pb PCSC as an example, we realize a device-level optoelectronic simulation to thoroughly disclose the internal photovoltaic physics and mechanisms by addressing the fundamental electromagnetic and carrier-transport processes within PCSCs under various concentration conditions. We find that the primary factor limiting the performance improvement of PCSCs is the significantly increased bulk recombination under the increased light concentration, which is attributed mostly to the inferior transport/collection ability of holes determined by the hole transport layer (HTL). We perform further electrical manipulation on the perovskite layer and the HTL so that the carrier-transport capability is significantly improved. Under the optoelectronic design, we fabricate low band gap PCSCs, which exhibit particularly high PCEs of up to 22.36% at 4.17 sun.
钙钛矿太阳能电池（PSCs）的功率转换效率（PCEs）迅速提高，但其聚光型电池（即PCSCs）的性能要低得多。要更深入地了解PCSCs，需要深入研究器件在光照强度增加时的能量损失。以低带隙Sn-Pb PCSC为例，我们通过解决不同聚光条件下PCSCs内部的基本电磁和载流子传输过程，实现了器件级的光电模拟，以全面揭示内部光伏物理和机制。我们发现，限制PCSCs性能提升的主要因素是在光强增加时体相复合显著增加，这主要归因于由空穴传输层（HTL）决定的空穴传输/收集能力较差。我们对钙钛矿层和HTL进行了进一步的电学调控，从而显著提高了载流子传输能力。在光电设计下，我们制备了低带隙PCSCs，在4.17个太阳光照下，其PCEs特别高，可达22.36%。
