Department of Materials Science and Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
Sci Rep. 2017 May 11;7(1):1775. doi: 10.1038/s41598-017-01897-9.
Stability concerns of organic solar cell devices have led to the development of alternative hole transporting layers such as NiO which lead to superior device life times over conventional Poly(3,4-ethylenedioxythiophene) Polystyrene sulfonate (PEDOT:PSS) buffered solar cells. From the printability of such devices, it is imperative to be able to print NiO layers in the organic solar cell devices with normal architecture which has so far remained unreported. In this manuscript, we report on the successful ink-jet printing of very thin NiO thin films with controlled thickness and morphology and their integration in organic solar cell devices. The parameters that were found to strongly affect the formation of a thin yet continuous NiO film were substrate surface treatment, drop spacing, and substrate temperature during printing. The effect of these parameters was investigated through detailed morphological characterization using optical and atomic force microscopy and the results suggested that one can achieve a transmittance of ~89% for a ~18 nm thin NiO film with uniform structure and morphology, fabricated using a drop spacing of 50 μm and a heat treatment temperature of 400 °C. The devices fabricated with printed NiO hole transporting layers exhibit power conversion efficiencies comparable to the devices with spin coated NiO films.
有机太阳能电池器件的稳定性问题促使人们开发了替代空穴传输层，例如 NiO，与传统的聚(3,4-亚乙基二氧噻吩)聚苯乙烯磺酸盐(PEDOT:PSS)缓冲太阳能电池相比，这导致器件寿命得到了显著提高。从这些器件的可印刷性出发，必须能够在具有常规结构的有机太阳能电池器件中打印 NiO 层，而这在以前是没有报道过的。在本文中，我们报告了成功地喷墨打印出具有可控厚度和形貌的超薄 NiO 薄膜，并将其集成到有机太阳能电池器件中。研究发现，基底表面处理、滴间距和打印过程中的基底温度等参数强烈影响着薄且连续的 NiO 薄膜的形成。通过使用光学和原子力显微镜进行详细的形态特征研究，研究了这些参数的影响，结果表明，可以通过使用 50 μm 的滴间距和 400°C 的热处理温度来实现约 18nm 厚的 NiO 薄膜的透光率约为 89%，该薄膜具有均匀的结构和形貌。使用印刷 NiO 空穴传输层制造的器件表现出与旋涂 NiO 薄膜器件相当的功率转换效率。
