Mali Sawanta S, Patil Jyoti V, Hong Chang Kook
Polymer Energy Materials Laboratory, School of Advanced Chemical Engineering , Chonnam National University , Gwangju 61186 , South Korea.
Nano Lett. 2019 Sep 11;19(9):6213-6220. doi: 10.1021/acs.nanolett.9b02277. Epub 2019 Aug 7.
Replacement of conventional organic cations by thermally stable inorganic cations in perovskite solar cells (PSCs) is one of the promising approaches to make thermally stable photovoltaics. However, conventional spin-coating and solvent-engineering processes in a controlled inert atmosphere hamper the upscaling. In this study, we demonstrated a dynamic hot-air (DHA) casting process to control the morphology and stability of all-inorganic PSCs which is processed under ambient conditions and free from conventional harmful antisolvents. Furthermore, CsPbIBr perovskite was doped with barium (Ba) alkaline earth metal cations (BaI:CsPbIBr). This DHA method facilitates the formation of uniform grain and controlled crystallization that makes stable all-inorganic PSCs which enables an intact black α-phase under ambient conditions. The DHA-processed BaI:CsPbIBr perovskite photovoltaics shows the champion power conversion efficiency (PCE) of 14.85% (reverse scan) for a small exposure area of 0.09 cm and 13.78% for a large area of 1 × 1 cm with excellent reproducibility. Interestingly, the hot-air-processed devices retain >92% of the initial efficiency after 300 h. This DHA method facilitates a wide processing window for upscaling the all-inorganic perovskite photovoltaics.
在钙钛矿太阳能电池（PSC）中用热稳定的无机阳离子取代传统的有机阳离子是制造热稳定光伏电池的一种有前景的方法。然而，在可控的惰性气氛中进行的传统旋涂和溶剂工程工艺阻碍了其扩大规模。在本研究中，我们展示了一种动态热风（DHA）铸造工艺，以控制在环境条件下加工且不含传统有害反溶剂的全无机PSC的形貌和稳定性。此外，CsPbIBr钙钛矿用钡（Ba）碱土金属阳离子（BaI:CsPbIBr）进行了掺杂。这种DHA方法有助于形成均匀的晶粒并控制结晶，从而制造出稳定的全无机PSC，使其在环境条件下能够形成完整的黑色α相。经DHA处理的BaI:CsPbIBr钙钛矿光伏电池在0.09平方厘米的小曝光面积下反向扫描时的最高功率转换效率（PCE）为14.85%，在1×1平方厘米的大面积下为13.78%，具有出色的可重复性。有趣的是，经过热风处理的器件在300小时后仍保留了初始效率的92%以上。这种DHA方法为扩大全无机钙钛矿光伏电池的规模提供了广阔的加工窗口。
