Proceedings of Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP20)
DOI: https://doi.org/10.29363/nanoge.iperop.2020.046
Publication date: 14th October 2019
Carbon based Perovskite Solar cells (C-PSCs) have emerged in recent years as the most promising candidates for commercialisation in perovskite photovoltaics. Constructed by screen-printing mesoporous Titania, Zirconia and Carbon and subsequent perovskite infiltration, these devices are highly stable, low cost and make use of easily scaled manufacturing techniques. However, while the lack of an expensive hole transport material decreases device cost and enhances stability, the limited conductivity of carbon electrodes also inhibits performance and represents a significant barrier to commercial application.
This work presents a method for electrode conductivity enhancement through the application of Aluminium and Copper grids to prefabricated C-PSCs. Adhered to cells using a low temperature carbon ink, metallic grids were found to dramatically reduce electrode series resistance, leading to a large improvement in Fill Factor and efficiency enhancement of up to 23.3 % in 1 cm2 devices. Average power conversion efficiencies (PCEs) of 13.15 ± 0.12 % and 12.83 ± 0.06 % were obtained for Copper and Aluminium respectively, up from ~11 % pre-application. Performance is also significantly augmented in the case of larger-scale 11.7 cm2 modules, where PCEs went from 7.73 % to 9.97 % and 7.70 % to 11.05 % for Aluminium and Copper grids respectively.
Grid structures are easily applied as the mesh structure allows ink permeation and hence top down deposition. The resultant bilateral coverage protects the grid and imparts mechanical stability without damaging the underlying layer. This technique offers a fast, cheap and low temperature route to high-performance, large-scale stable C-PSCs and could therefore have serious potential for application to the high-volume manufacture of large-scale perovskite devices.