Wang Lei, Zhang Ting, Yuan Shihao, Qian Feng, Li Xiaobo, Zheng Hualin, Huang Jiang, Li Shibin
School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China.
ACS Appl Mater Interfaces. 2024 Jan 31;16(4):4751-4762. doi: 10.1021/acsami.3c16317. Epub 2024 Jan 19.
Perovskite solar cells (PSCs) based on sputtered nickel oxide (NiO) hole transport layer have emerged as promising configuration due to their good stability, cost-effectiveness, and scalability. However, the adverse chemical redox reaction at the NiO/perovskite interface remains an ever-present problem that has not yet been well solved. To address this issue before, the problems that cation deprotonation and iodide oxidation that occurred in precursor solution easily result in the interfacial chemical reaction should be prevented. Hence, we report an efficient strategy to simultaneously suppress the interfacial reaction and stabilize the precursor solution by incorporating a reducing and weakly acidic stabilizer, l-ascorbic acid (l-AA). l-AA can reduce I generated in the precursor solution and during the interfacial reaction to I. Furthermore, the protons ionized by adjacent enol hydroxyl groups in l-AA effectively impede the deprotonation of organic cations in the precursor solution as well as at the NiO/perovskite interface resulting from the chemical reaction. Attributing to the improved crystallization of the perovskite film and the suppression of the interfacial reaction by l-AA, the inverted PSC based on such good light absorber achieves an impressive power conversion efficiency (PCE) of 22.72% along with a high open-circuit voltage of 1.19 V. Notably, further introducing l-AA into the large-area solar modules by the slot-die coating method in air enables a remarkable PCE of 19.17%, which reaches one of the highest PCEs reported for inverted perovskite solar modules (PSMs) (active area >50 cm) to date. l-AA located at the buried interface also forms a barrier layer that can prevent undesirable chemical reactions at the NiO/perovskite interface, significantly enhancing the device stability of solar cells and PSMs. These findings in our work provide important guidance for improving the NiO/perovskite interface and the fabrication of highly efficient, low-cost, and large-area PSMs.
基于溅射氧化镍（NiO）空穴传输层的钙钛矿太阳能电池（PSC）因其良好的稳定性、成本效益和可扩展性而成为一种很有前景的结构。然而，NiO/钙钛矿界面处的不利化学氧化还原反应仍然是一个尚未得到很好解决的长期存在的问题。为了之前解决这个问题，应该防止前驱体溶液中发生的阳离子去质子化和碘化物氧化等容易导致界面化学反应的问题。因此，我们报告了一种有效的策略，通过加入一种还原性和弱酸性稳定剂l-抗坏血酸（l-AA）来同时抑制界面反应并稳定前驱体溶液。l-AA可以将前驱体溶液中以及界面反应过程中产生的I还原为I。此外，l-AA中相邻烯醇羟基电离出的质子有效地阻碍了前驱体溶液中以及化学反应导致的NiO/钙钛矿界面处有机阳离子的去质子化。由于l-AA改善了钙钛矿薄膜的结晶并抑制了界面反应，基于这种良好光吸收体的倒置PSC实现了令人印象深刻的22.72%的功率转换效率（PCE）以及1.19 V的高开路电压。值得注意的是，通过在空气中的狭缝模涂覆法将l-AA进一步引入大面积太阳能模块中，可实现19.17%的显著PCE，这达到了迄今为止报道的倒置钙钛矿太阳能模块（PSM）（活性面积>50 cm）的最高PCE之一。位于掩埋界面处的l-AA还形成了一个阻挡层，可以防止NiO/钙钛矿界面处的不良化学反应，显著提高太阳能电池和PSM的器件稳定性。我们工作中的这些发现为改善NiO/钙钛矿界面以及制造高效、低成本和大面积PSM提供了重要指导。
