Srivastava Ravi P, Jung Hyun-Suh, Khang Dahl-Young
Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea.
Nanomaterials (Basel). 2022 Apr 26;12(9):1467. doi: 10.3390/nano12091467.
Perovskite solar cells (PSCs) have achieved significantly high power-conversion efficiency within a short time. Most of the devices, including those with the highest efficiency, are based on a n-i-p structure utilizing a (doped) spiro-OMeTAD hole transport layer (HTL), which is an expensive material. Furthermore, doping has its own challenges affecting the processing and performance of the devices. Therefore, the need for low-cost, dopant-free hole transport materials is an urgent and critical issue for the commercialization of PSCs. In this study, n-i-p structure PSCs were fabricated in an ambient environment with cuprous iodide (CuI) HTL, employing a novel transfer-printing technique, in order to avoid the harmful interaction between the perovskite surface and the solvents of CuI. Moreover, in fabricated PSCs, the SnO electron transport layer (ETL) has been incorporated to reduce the processing temperature, as previously reported (n-i-p) devices with CuI HTL are based on TiO, which is a high-temperature processed ETL. PSCs fabricated at 80 °C transfer-printing temperature with 20 nm iodized copper, under 1 sun illumination showed a promising efficiency of 8.3%, (J and FF; 19.3 A/cm and 53.8%), which is comparable with undoped spiro-OMeTAD PSCs and is the highest among the ambient-environment-fabricated PSCs utilizing CuI HTL.
钙钛矿太阳能电池（PSCs）在短时间内已实现了显著的高功率转换效率。大多数器件，包括那些效率最高的器件，都基于采用（掺杂的）螺环-OMeTAD空穴传输层（HTL）的n-i-p结构，而这是一种昂贵的材料。此外，掺杂本身也存在影响器件加工和性能的挑战。因此，对于PSCs商业化而言，低成本、无掺杂的空穴传输材料的需求是一个紧迫且关键的问题。在本研究中，采用一种新颖的转移印刷技术，在环境气氛中用碘化亚铜（CuI）HTL制备了n-i-p结构的PSCs，以避免钙钛矿表面与CuI溶剂之间的有害相互作用。此外，在制备的PSCs中，已引入SnO电子传输层（ETL）以降低加工温度，因为先前报道的具有CuI HTL的（n-i-p）器件基于TiO，这是一种经过高温处理的ETL。在80℃转移印刷温度下用20nm碘化铜制备的PSCs，在1个太阳光照下显示出有前景的8.3%的效率（J和FF；19.3mA/cm²和53.8%），这与未掺杂的螺环-OMeTAD PSCs相当，并且是在环境气氛中制备的利用CuI HTL的PSCs中效率最高的。
